Commit Graph

15974 Commits

Author SHA1 Message Date
Thomas Gleixner
adefe55e72 x86/kernel: Convert to new CPU match macros
The new macro set has a consistent namespace and uses C99 initializers
instead of the grufty C89 ones.

Get rid the of the local macro wrappers for consistency.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131509.250559388@linutronix.de
2020-03-24 21:28:26 +01:00
Thomas Gleixner
f6d502fcfc x86/cpu/bugs: Convert to new matching macros
The new macro set has a consistent namespace and uses C99 initializers
instead of the grufty C89 ones.

The local wrappers have to stay as they are tailored to tame the hardware
vulnerability mess.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131508.934926587@linutronix.de
2020-03-24 21:22:23 +01:00
Thomas Gleixner
20d437447c x86/cpu: Add consistent CPU match macros
Finding all places which build x86_cpu_id match tables is tedious and the
logic is hidden in lots of differently named macro wrappers.

Most of these initializer macros use plain C89 initializers which rely on
the ordering of the struct members. So new members could only be added at
the end of the struct, but that's ugly as hell and C99 initializers are
really the right thing to use.

Provide a set of macros which:

  - Have a proper naming scheme, starting with X86_MATCH_

  - Use C99 initializers

The set of provided macros are all subsets of the base macro

    X86_MATCH_VENDOR_FAM_MODEL_FEATURE()

which allows to supply all possible selection criteria:

      vendor, family, model, feature

The other macros shorten this to avoid typing all arguments when they are
not needed and would require one of the _ANY constants. They have been
created due to the requirements of the existing usage sites.

Also add a few model constants for Centaur CPUs and QUARK.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131508.826011988@linutronix.de
2020-03-24 21:17:50 +01:00
Alexey Makhalov
8fefe9dacd x86/vmware: Use bool type for vmw_sched_clock
To be aligned with other bool variables.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-6-amakhalov@vmware.com
2020-03-24 10:29:22 +01:00
Alexey Makhalov
e73a8f38f8 x86/vmware: Enable steal time accounting
Set paravirt_steal_rq_enabled if steal clock present.
paravirt_steal_rq_enabled is used in sched/core.c to adjust task
progress by offsetting stolen time. Use 'no-steal-acc' off switch (share
same name with KVM) to disable steal time accounting.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-5-amakhalov@vmware.com
2020-03-24 10:06:27 +01:00
Alexey Makhalov
ab02bb3f55 x86/vmware: Add steal time clock support for VMware guests
Steal time is the amount of CPU time needed by a guest virtual machine
that is not provided by the host. Steal time occurs when the host
allocates this CPU time elsewhere, for example, to another guest.

Steal time can be enabled by adding the VM configuration option
stealclock.enable = "TRUE". It is supported by VMs that run hardware
version 13 or newer.

Introduce the VMware steal time infrastructure. The high level code
(such as enabling, disabling and hot-plug routines) was derived from KVM.

 [ Tomer: use READ_ONCE macros and 32bit guests support. ]
 [ bp: Massage. ]

Co-developed-by: Tomer Zeltzer <tomerr90@gmail.com>
Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Tomer Zeltzer <tomerr90@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-4-amakhalov@vmware.com
2020-03-24 10:04:51 +01:00
Alexey Makhalov
dd735f4707 x86/vmware: Remove vmware_sched_clock_setup()
Move cyc2ns setup logic to separate function.
This separation will allow to use cyc2ns mult/shift pair
not only for the sched_clock but also for other clocks
such as steal_clock.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-3-amakhalov@vmware.com
2020-03-24 09:31:06 +01:00
Alexey Makhalov
14388ae245 x86/vmware: Make vmware_select_hypercall() __init
vmware_select_hypercall() is used only by the __init
functions, and should be annotated with __init as well.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-2-amakhalov@vmware.com
2020-03-24 09:26:04 +01:00
Benjamin Thiel
0e79ad863d x86/cpu: Fix a -Wmissing-prototypes warning for init_ia32_feat_ctl()
Add a missing include in order to fix -Wmissing-prototypes warning:

  arch/x86/kernel/cpu/feat_ctl.c:95:6: warning: no previous prototype for ‘init_ia32_feat_ctl’ [-Wmissing-prototypes]
     95 | void init_ia32_feat_ctl(struct cpuinfo_x86 *c)

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200323105934.26597-1-b.thiel@posteo.de
2020-03-23 12:01:59 +01:00
Wei Huang
077168e241 x86/mce/amd: Add PPIN support for AMD MCE
Newer AMD CPUs support a feature called protected processor
identification number (PPIN). This feature can be detected via
CPUID_Fn80000008_EBX[23].

However, CPUID alone is not enough to read the processor identification
number - MSR_AMD_PPIN_CTL also needs to be configured properly. If, for
any reason, MSR_AMD_PPIN_CTL[PPIN_EN] can not be turned on, such as
disabled in BIOS, the CPU capability bit X86_FEATURE_AMD_PPIN needs to
be cleared.

When the X86_FEATURE_AMD_PPIN capability is available, the
identification number is issued together with the MCE error info in
order to keep track of the source of MCE errors.

 [ bp: Massage. ]

Co-developed-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com>
Signed-off-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com>
Signed-off-by: Wei Huang <wei.huang2@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200321193800.3666964-1-wei.huang2@amd.com
2020-03-22 11:03:47 +01:00
Brian Gerst
ffd75b373f x86: Remove unneeded includes
Clean up includes of and in <asm/syscalls.h>

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-19-brgerst@gmail.com
2020-03-21 16:03:25 +01:00
Brian Gerst
121b32a58a x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments
For the 32-bit syscall interface, 64-bit arguments (loff_t) are passed via
a pair of 32-bit registers.  These register pairs end up in consecutive stack
slots, which matches the C ABI for 64-bit arguments.  But when accessing the
registers directly from pt_regs, the wrapper needs to manually reassemble the
64-bit value.  These wrappers already exist for 32-bit compat, so make them
available to 32-bit native in preparation for enabling pt_regs-based syscalls.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Link: https://lkml.kernel.org/r/20200313195144.164260-16-brgerst@gmail.com
2020-03-21 16:03:24 +01:00
Brian Gerst
0872098804 x86/entry: Move max syscall number calculation to syscallhdr.sh
Instead of using an array in asm-offsets to calculate the max syscall
number, calculate it when writing out the syscall headers.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200313195144.164260-9-brgerst@gmail.com
2020-03-21 16:03:21 +01:00
Brian Gerst
27dd84fafc x86/entry/64: Use syscall wrappers for x32_rt_sigreturn
Add missing syscall wrapper for x32_rt_sigreturn().

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200313195144.164260-6-brgerst@gmail.com
2020-03-21 16:03:20 +01:00
afzal mohammed
4dd2a1b92b x86: Replace setup_irq() by request_irq()
request_irq() is preferred over setup_irq(). The early boot setup_irq()
invocations happen either via 'init_IRQ()' or 'time_init()', while
memory allocators are ready by 'mm_init()'.

setup_irq() was required in old kernels when allocators were not ready by
the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

[ tglx: Use a local variable and get rid of the line break. Tweak the
  	comment a bit ]

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/17f85021f6877650a5b09e0212d88323e6a30fd0.1582471508.git.afzal.mohd.ma@gmail.com
2020-03-21 15:15:47 +01:00
Peter Zijlstra
d8a7386897 x86/optprobe: Fix OPTPROBE vs UACCESS
While looking at an objtool UACCESS warning, it suddenly occurred to me
that it is entirely possible to have an OPTPROBE right in the middle of
an UACCESS region.

In this case we must of course clear FLAGS.AC while running the KPROBE.
Luckily the trampoline already saves/restores [ER]FLAGS, so all we need
to do is inject a CLAC. Unfortunately we cannot use ALTERNATIVE() in the
trampoline text, so we have to frob that manually.

Fixes: ca0bbc70f147 ("sched/x86_64: Don't save flags on context switch")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20200305092130.GU2596@hirez.programming.kicks-ass.net
2020-03-20 13:06:22 +01:00
Guenter Roeck
bac59d18c7 x86/setup: Fix static memory detection
When booting x86 images in qemu, the following warning is seen randomly
if DEBUG_LOCKDEP is enabled.

  WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:1119
	  lockdep_register_key+0xc0/0x100

static_obj() returns true if an address is between _stext and _end.

On x86, this includes the brk memory space. Problem is that this memory
block is not static on x86; its unused portions are released after init
and can be allocated. This results in the observed warning if a lockdep
object is allocated from this memory.

Solve the problem by implementing arch_is_kernel_initmem_freed() for
x86 and have it return true if an address is within the released memory
range.

The same problem was solved for s390 with commit

  7a5da02de8 ("locking/lockdep: check for freed initmem in static_obj()"),

which introduced arch_is_kernel_initmem_freed().

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200131021159.9178-1-linux@roeck-us.net
2020-03-19 11:58:13 +01:00
Al Viro
39f16c1c0f x86: get rid of put_user_try in {ia32,x32}_setup_rt_frame()
Straightforward, except for compat_save_altstack_ex() stuck in those.
Replace that thing with an analogue that would use unsafe_put_user()
instead of put_user_ex() (called unsafe_compat_save_altstack()) and
be done with that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-19 00:37:49 -04:00
Al Viro
9f855c085f x86: switch setup_sigcontext() to unsafe_put_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:39:02 -04:00
Al Viro
a37d01ead4 x86: switch save_v86_state() to unsafe_put_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:36:01 -04:00
Al Viro
3add42c29c x86: get rid of get_user_ex() in restore_sigcontext()
Just do copyin into a local struct and be done with that - we are
on a shallow stack here.

[reworked by tglx, removing the macro horrors while we are touching that]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:22:40 -04:00
Al Viro
c63aad695d vm86: get rid of get_user_ex() use
Just do a copyin of what we want into a local variable and
be done with that.  We are guaranteed to be on shallow stack
here...

Note that conditional expression for range passed to access_ok()
in mainline had been pointless all along - the only difference
between vm86plus_struct and vm86_struct is that the former has
one extra field in the end and when we get to copyin of that
field (conditional upon 'plus' argument), we use copy_from_user().
Moreover, all fields starting with ->int_revectored are copied
that way, so we only need that check (be it done by access_ok()
or by user_access_begin()) only on the beginning of the structure -
the fields that used to be covered by that get_user_try() block.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 20:04:00 -04:00
Al Viro
71c3313a38 x86: switch sigframe sigset handling to explict __get_user()/__put_user()
... and consolidate the definition of sigframe_ia32->extramask - it's
always a 1-element array of 32bit unsigned.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-18 15:29:54 -04:00
Borislav Petkov
19d33357ec x86/amd_nb, char/amd64-agp: Use amd_nb_num() accessor
... to find whether there are northbridges present on the
system. Convert the last forgotten user and therefore, unexport
amd_nb_misc_ids[] too.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Michal Kubecek <mkubecek@suse.cz>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>
Link: https://lkml.kernel.org/r/20200316150725.925-1-bp@alien8.de
2020-03-17 10:25:58 +01:00
Linus Torvalds
ec181b7f30 Two fixes for x86:
- Map EFI runtime service data as encrypted when SEV is enabled otherwise
     e.g. SMBIOS data cannot be properly decoded by dmidecode.
 
   - Remove the warning in the vector management code which triggered when a
     managed interrupt affinity changed outside of a CPU hotplug
     operation. The warning was correct until the recent core code change
     that introduced a CPU isolation feature which needs to migrate managed
     interrupts away from online CPUs under certain conditions to achieve the
     isolation.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl5uRi8THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoSH9EACToDM3iADmLZnP4dookJpPWvxazCio
 UclqaIUE7k2Wg/EPmE0oNTQCxqh42rTX6Ifo5WaiCJbxIFZKGMhe02BwmQffilaS
 dOlxuEEeLQq3S4Ai10Mq7wcp5uVHCE/+IhaphwFrdPn/w99O0SZf/bpZMveh6xgR
 Qw3vMLav9FXpWqvnDTw0Vcrcd9sEnZ/iaLrXVDFAnwZggrUqq26Ia4DqUlOaiHGC
 DHESmYFlHcFqfzd6BOJXbsJqedL56Qav0n7zsIqz6B34cLyc8QOqnSn2HxzncP22
 BLPVLvdLi7yqrWIoVgSefcAJq1wcE+Vl9V6mvjxMK4GieYZ91WdLKIbvqUPRZvhU
 viDzZ7NCsg6TmQBD6ilvYrMNB9ds+GNl/1dZ9c854zuvnTcnKqRq9CE6djnlqaLw
 AfHQQJ+kPjrnVyyPnyYBqrWgfsVJ3ueE8BEPtTfruL2CDQLrwiScwCNZ3qQmZ6Bx
 r00wbx+QtATHiZ97pwR1FJr1gyuZE6q3tY3gnb5ORIY19DfkwzRprKpE+Z++3N1H
 Z5Vc7A67CcQe6uCwyViJZuamNgBaXvFmbDDjt3d8N4KKnLK647WyW0XutabQppWa
 Jueq9XJX2V752y81i2Gf2+/U7xGOK0C4QajRMbqiizRBHKiG1JXpi9yCrdqNldEP
 ocz5HASe634nng==
 =KeLM
 -----END PGP SIGNATURE-----

Merge tag 'x86-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for x86:

   - Map EFI runtime service data as encrypted when SEV is enabled.

     Otherwise e.g. SMBIOS data cannot be properly decoded by dmidecode.

   - Remove the warning in the vector management code which triggered
     when a managed interrupt affinity changed outside of a CPU hotplug
     operation.

     The warning was correct until the recent core code change that
     introduced a CPU isolation feature which needs to migrate managed
     interrupts away from online CPUs under certain conditions to
     achieve the isolation"

* tag 'x86-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vector: Remove warning on managed interrupt migration
  x86/ioremap: Map EFI runtime services data as encrypted for SEV
2020-03-15 12:52:56 -07:00
Linus Torvalds
52ac3777fc Two RAS related fixes:
- Shut down the per CPU thermal throttling poll work properly when a CPU
     goes offline. The missing shutdown caused the poll work to be migrated
     to a unbound worker which triggered warnings about the usage of
     smp_processor_id() in preemptible context
 
   - Fix the PPIN feature initialization which missed to enable the
     functionality when PPIN_CTL was enabled but the MSR locked against
     updates.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl5uRHUTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoVVGD/0WEjZoB8yhwez6u0YNFhUkjfP8JFC1
 mGdWMoevyH3Tb+DQNX3cW95t2O7IxP0N6OUNnYYQ9Tlqwt6r0ptJpNnXO7CV2+Jh
 5lxpw/Uv2kQv69BNDK9qPDhiIBPzZQCg/utDTVdIyG0y+XU0q/IZqXh+XedAJsVr
 P3U7KC//NwTYnlpPWjDsG26GHSguV4kj+Lwi88nfh1DJ7eawb8AF4k965pLmOoF9
 g13EFxv2FW1/uq+QJq5ophQIH/pPI/T67rhIyLWxFsCByBzVKjm4BBgXH4gb+QIn
 OofVQcaWCpZCOq2ZTNfHWdPvJK2ziig9w+twbArb7Cb9aOgp3Oe1zbp2VD4nKu4+
 0G5E2Vdv6qRrEIk5LUTqlyOIogd5xPSufaCGF/HC/qXqBxqwWD0tUvjtYyRwwy+Y
 u90bo90zlMjUoDirgtZrjYe0bXuy3xJ+FxZ5OxovGRxLn4qqBqEJGrXYvB0LIlpd
 3x+YeHB4T2pwC6Ya5Odi6RKhwMKpro24dDMJ9jIR1u/NwIgJ2elSO9bsw6SZ823e
 /Mwns7CC/7xtjOCJXPlyj4Uw0TzwTbp1W9Kb0OqJo6q+ntvxbAhoMf32FDxg0OKC
 h4trc3FZt+e2a0l8R8e3nNeAvnS0fM1P4vtg18EcX8SqlSoALJkS3XUO4WeCFLBh
 F9jOt/LSf+4okQ==
 =9W7B
 -----END PGP SIGNATURE-----

Merge tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS fixes from Thomas Gleixner:
 "Two RAS related fixes:

   - Shut down the per CPU thermal throttling poll work properly when a
     CPU goes offline.

     The missing shutdown caused the poll work to be migrated to a
     unbound worker which triggered warnings about the usage of
     smp_processor_id() in preemptible context

   - Fix the PPIN feature initialization which missed to enable the
     functionality when PPIN_CTL was enabled but the MSR locked against
     updates"

* tag 'ras-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix logic and comments around MSR_PPIN_CTL
  x86/mce/therm_throt: Undo thermal polling properly on CPU offline
2020-03-15 12:44:23 -07:00
Jan Engelhardt
ecb9c79099 acpi/x86: ignore unspecified bit positions in the ACPI global lock field
The value in "new" is constructed from "old" such that all bits defined
as reserved by the ACPI spec[1] are left untouched. But if those bits
do not happen to be all zero, "new < 3" will not evaluate to true.

The firmware of the laptop(s) Medion MD63490 / Akoya P15648 comes with
garbage inside the "FACS" ACPI table. The starting value is
old=0x4944454d, therefore new=0x4944454e, which is >= 3. Mask off
the reserved bits.

[1] https://uefi.org/sites/default/files/resources/ACPI_6_2.pdf

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206553
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Jan Engelhardt <jengelh@inai.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:41:56 +01:00
Alex Hung
1ffb8d032d acpi/x86: add a kernel parameter to disable ACPI BGRT
BGRT is for displaying seamless OEM logo from booting to login screen;
however, this mechanism does not always work well on all configurations
and the OEM logo can be displayed multiple times. This looks worse than
without BGRT enabled.

This patch adds a kernel parameter to disable BGRT in boot time. This is
easier than re-compiling a kernel with CONFIG_ACPI_BGRT disabled.

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:36:49 +01:00
Alexey Dobriyan
fa0fca68e1 x86/acpi: make "asmlinkage" part first thing in the function definition
g++ insists that function declaration must start with extern "C"
(which asmlinkage expands to).

gcc doesn't care.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:29:07 +01:00
Peter Xu
469ff207b4 x86/vector: Remove warning on managed interrupt migration
The vector management code assumes that managed interrupts cannot be
migrated away from an online CPU. free_moved_vector() has a WARN_ON_ONCE()
which triggers when a managed interrupt vector association on a online CPU
is cleared. The CPU offline code uses a different mechanism which cannot
trigger this.

This assumption is not longer correct because the new CPU isolation feature
which affects the placement of managed interrupts must be able to move a
managed interrupt away from an online CPU.

There are two reasons why this can happen:

  1) When the interrupt is activated the affinity mask which was
     established in irq_create_affinity_masks() is handed in to
     the vector allocation code. This mask contains all CPUs to which
     the interrupt can be made affine to, but this does not take the
     CPU isolation 'managed_irq' mask into account.

     When the interrupt is finally requested by the device driver then the
     affinity is checked again and the CPU isolation 'managed_irq' mask is
     taken into account, which moves the interrupt to a non-isolated CPU if
     possible.

  2) The interrupt can be affine to an isolated CPU because the
     non-isolated CPUs in the calculated affinity mask are not online.

     Once a non-isolated CPU which is in the mask comes online the
     interrupt is migrated to this non-isolated CPU

In both cases the regular online migration mechanism is used which triggers
the WARN_ON_ONCE() in free_moved_vector().

Case #1 could have been addressed by taking the isolation mask into
account, but that would require a massive code change in the activation
logic and the eventual migration event was accepted as a reasonable
tradeoff when the isolation feature was developed. But even if #1 would be
addressed, #2 would still trigger it.

Of course the warning in free_moved_vector() was overlooked at that time
and the above two cases which have been discussed during patch review have
obviously never been tested before the final submission.

So keep it simple and remove the warning.

[ tglx: Rewrote changelog and added a comment to free_moved_vector() ]

Fixes: 11ea68f553 ("genirq, sched/isolation: Isolate from handling managed interrupts")
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>                                                                                                                                                                       
Link: https://lkml.kernel.org/r/20200312205830.81796-1-peterx@redhat.com
2020-03-13 15:29:26 +01:00
Nayna Jain
9e2b4be377 ima: add a new CONFIG for loading arch-specific policies
Every time a new architecture defines the IMA architecture specific
functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA
include file needs to be updated. To avoid this "noise", this patch
defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing
the different architectures to select it.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Philipp Rudo <prudo@linux.ibm.com> (s390)
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-03-12 07:43:57 -04:00
Kim Phillips
753039ef8b x86/cpu/amd: Call init_amd_zn() om Family 19h processors too
Family 19h CPUs are Zen-based and still share most architectural
features with Family 17h CPUs, and therefore still need to call
init_amd_zn() e.g., to set the RECLAIM_DISTANCE override.

init_amd_zn() also sets X86_FEATURE_ZEN, which today is only used
in amd_set_core_ssb_state(), which isn't called on some late
model Family 17h CPUs, nor on any Family 19h CPUs:
X86_FEATURE_AMD_SSBD replaces X86_FEATURE_LS_CFG_SSBD on those
later model CPUs, where the SSBD mitigation is done via the
SPEC_CTRL MSR instead of the LS_CFG MSR.

Family 19h CPUs also don't have the erratum where the CPB feature
bit isn't set, but that code can stay unchanged and run safely
on Family 19h.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200311191451.13221-1-kim.phillips@amd.com
2020-03-12 12:13:44 +01:00
Hans de Goede
fac01d1172 x86/tsc_msr: Make MSR derived TSC frequency more accurate
The "Intel 64 and IA-32 Architectures Software Developer’s Manual Volume 4:
Model-Specific Registers" has the following table for the values from
freq_desc_byt:

   000B: 083.3 MHz
   001B: 100.0 MHz
   010B: 133.3 MHz
   011B: 116.7 MHz
   100B: 080.0 MHz

Notice how for e.g the 83.3 MHz value there are 3 significant digits, which
translates to an accuracy of a 1000 ppm, where as a typical crystal
oscillator is 20 - 100 ppm, so the accuracy of the frequency format used in
the Software Developer’s Manual is not really helpful.

As far as we know Bay Trail SoCs use a 25 MHz crystal and Cherry Trail
uses a 19.2 MHz crystal, the crystal is the source clock for a root PLL
which outputs 1600 and 100 MHz. It is unclear if the root PLL outputs are
used directly by the CPU clock PLL or if there is another PLL in between.

This does not matter though, we can model the chain of PLLs as a single PLL
with a quotient equal to the quotients of all PLLs in the chain multiplied.

So we can create a simplified model of the CPU clock setup using a
reference clock of 100 MHz plus a quotient which gets us as close to the
frequency from the SDM as possible.

For the 83.3 MHz example from above this would give 100 MHz * 5 / 6 = 83
and 1/3 MHz, which matches exactly what has been measured on actual
hardware.

Use a simplified PLL model with a reference clock of 100 MHz for all Bay
and Cherry Trail models.

This has been tested on the following models:

              CPU freq before:        CPU freq after:
Intel N2840   2165.800 MHz            2166.667 MHz
Intel Z3736   1332.800 MHz            1333.333 MHz
Intel Z3775   1466.300 MHz            1466.667 MHz
Intel Z8350   1440.000 MHz            1440.000 MHz
Intel Z8750   1600.000 MHz            1600.000 MHz

This fixes the time drifting by about 1 second per hour (20 - 30 seconds
per day) on (some) devices which rely on the tsc_msr.c code to determine
the TSC frequency.

Reported-by: Vipul Kumar <vipulk0511@gmail.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200223140610.59612-3-hdegoede@redhat.com
2020-03-11 22:57:40 +01:00
Hans de Goede
c8810e2ffc x86/tsc_msr: Fix MSR_FSB_FREQ mask for Cherry Trail devices
According to the "Intel 64 and IA-32 Architectures Software Developer's
Manual Volume 4: Model-Specific Registers" on Cherry Trail (Airmont)
devices the 4 lowest bits of the MSR_FSB_FREQ mask indicate the bus freq
unlike on e.g. Bay Trail where only the lowest 3 bits are used.

This is also the reason why MAX_NUM_FREQS is defined as 9, since Cherry
Trail SoCs have 9 possible frequencies, so the lo value from the MSR needs
to be masked with 0x0f, not with 0x07 otherwise the 9th frequency will get
interpreted as the 1st.

Bump MAX_NUM_FREQS to 16 to avoid any possibility of addressing the array
out of bounds and makes the mask part of the cpufreq struct so it can be
set it per model.

While at it also log an error when the index points to an uninitialized
part of the freqs lookup-table.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200223140610.59612-2-hdegoede@redhat.com
2020-03-11 22:57:39 +01:00
Hans de Goede
812c2d7506 x86/tsc_msr: Use named struct initializers
Use named struct initializers for the freq_desc struct-s initialization
and change the "u8 msr_plat" to a "bool use_msr_plat" to make its meaning
more clear instead of relying on a comment to explain it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200223140610.59612-1-hdegoede@redhat.com
2020-03-11 22:57:39 +01:00
Tony Luck
d8ecca4043 x86/mce/dev-mcelog: Dynamically allocate space for machine check records
We have had a hard coded limit of 32 machine check records since the
dawn of time.  But as numbers of cores increase, it is possible for
more than 32 errors to be reported before a user process reads from
/dev/mcelog. In this case the additional errors are lost.

Keep 32 as the minimum. But tune the maximum value up based on the
number of processors.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200218184408.GA23048@agluck-desk2.amr.corp.intel.com
2020-03-10 10:25:14 +01:00
Thomas Gleixner
008f1d60fe x86/apic/vector: Force interupt handler invocation to irq context
Sathyanarayanan reported that the PCI-E AER error injection mechanism
can result in a NULL pointer dereference in apic_ack_edge():

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000078
 RIP: 0010:apic_ack_edge+0x1e/0x40
 Call Trace:
   handle_edge_irq+0x7d/0x1e0
   generic_handle_irq+0x27/0x30
   aer_inject_write+0x53a/0x720

It crashes in irq_complete_move() which dereferences get_irq_regs() which
is obviously NULL when this is called from non interrupt context.

Of course the pointer could be checked, but that just papers over the real
issue. Invoking the low level interrupt handling mechanism from random code
can wreckage the fragile interrupt affinity mechanism of x86 as interrupts
can only be moved in interrupt context or with special care when a CPU goes
offline and the move has to be enforced.

In the best case this triggers the warning in the MSI affinity setter, but
if the call happens on the correct CPU it just corrupts state and might
prevent further interrupt delivery for the affected device.

Mark the APIC interrupts as unsuitable for being invoked in random contexts.

This prevents the AER injection from proliferating the wreckage, but that's
less broken than the current state of affairs and more correct than just
papering over the problem by sprinkling random checks all over the place
and silently corrupting state.

Reported-by: sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200306130623.684591280@linutronix.de
2020-03-08 11:06:40 +01:00
Arvind Sankar
8acf63efa1 efi/x86: Avoid using code32_start
code32_start is meant for 16-bit real-mode bootloaders to inform the
kernel where the 32-bit protected mode code starts. Nothing in the
protected mode kernel except the EFI stub uses it.

efi_main() currently returns boot_params, with code32_start set inside it
to tell efi_stub_entry() where startup_32 is located. Since it was invoked
by efi_stub_entry() in the first place, boot_params is already known.
Return the address of startup_32 instead.

This will allow a 64-bit kernel to live above 4Gb, for example, and it's
cleaner as well.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200301230436.2246909-5-nivedita@alum.mit.edu
Link: https://lore.kernel.org/r/20200308080859.21568-13-ardb@kernel.org
2020-03-08 09:58:17 +01:00
Ingo Molnar
6120681bdf Merge branch 'efi/urgent' into efi/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-08 09:57:58 +01:00
Ingo Molnar
1b10d388d0 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-06 12:49:56 +01:00
Linus Torvalds
2873dc2547 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes: a pkeys fix for a bug that triggers with weird BIOS
  settings, and two Xen PV fixes: a paravirt interface fix, and
  pagetable dumping fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix dump_pagetables with Xen PV
  x86/ioperm: Add new paravirt function update_io_bitmap()
  x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes
2020-03-02 06:54:54 -06:00
Linus Torvalds
f853ed90e2 More bugfixes, including a few remaining "make W=1" issues such
as too large frame sizes on some configurations.  On the
 ARM side, the compiler was messing up shadow stacks between
 EL1 and EL2 code, which is easily fixed with __always_inline.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJeXAT4AAoJEL/70l94x66DWywH/1kv4MmeGo6PI0Nxk/yvA7X8
 78iqIBchtxZX0v/9kqpTB7bYmHyTgmZHM+IkwtIUANDSaOvWqJwU+TLUfduOiuXF
 NxBHcZDyuMoftX5CSQ+bJ5PwxKijAdJsIkCZ13CnsTCkwcfamSGypFUCK8LacPeq
 WHvV5Ws5pFc51xrP3CH1DrRhLoulaBmt5xxqK9fxWtslrlsnm1uNza5vs8As8CzM
 apnmdRIf5p4v91Zic3PFH7/GXES0m1tjIBKdtZ4YHb8yrXV/kBsEVhhTjqE9mrUq
 qtRRl5waOFoP4yc9ey52PAbMm1x1Ho/pyunpM0xh40Yq8OPFwqXBPTnWfobSoiM=
 =LNQc
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "More bugfixes, including a few remaining "make W=1" issues such as too
  large frame sizes on some configurations.

  On the ARM side, the compiler was messing up shadow stacks between EL1
  and EL2 code, which is easily fixed with __always_inline"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: check descriptor table exits on instruction emulation
  kvm: x86: Limit the number of "kvm: disabled by bios" messages
  KVM: x86: avoid useless copy of cpufreq policy
  KVM: allow disabling -Werror
  KVM: x86: allow compiling as non-module with W=1
  KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
  KVM: Introduce pv check helpers
  KVM: let declaration of kvm_get_running_vcpus match implementation
  KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter
  arm64: Ask the compiler to __always_inline functions used by KVM at HYP
  KVM: arm64: Define our own swab32() to avoid a uapi static inline
  KVM: arm64: Ask the compiler to __always_inline functions used at HYP
  kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()
  KVM: arm/arm64: Fix up includes for trace.h
2020-03-01 15:16:35 -06:00
Juergen Gross
99bcd4a6e5 x86/ioperm: Add new paravirt function update_io_bitmap()
Commit 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm()
as well") reworked the iopl syscall to use I/O bitmaps.

Unfortunately this broke Xen PV domains using that syscall as there is
currently no I/O bitmap support in PV domains.

Add I/O bitmap support via a new paravirt function update_io_bitmap which
Xen PV domains can use to update their I/O bitmaps via a hypercall.

Fixes: 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm() as well")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cc: <stable@vger.kernel.org> # 5.5
Link: https://lkml.kernel.org/r/20200218154712.25490-1-jgross@suse.com
2020-02-29 12:43:09 +01:00
Wanpeng Li
8a9442f49c KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
Nick Desaulniers Reported:

  When building with:
  $ make CC=clang arch/x86/ CFLAGS=-Wframe-larger-than=1000
  The following warning is observed:
  arch/x86/kernel/kvm.c:494:13: warning: stack frame size of 1064 bytes in
  function 'kvm_send_ipi_mask_allbutself' [-Wframe-larger-than=]
  static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int
  vector)
              ^
  Debugging with:
  https://github.com/ClangBuiltLinux/frame-larger-than
  via:
  $ python3 frame_larger_than.py arch/x86/kernel/kvm.o \
    kvm_send_ipi_mask_allbutself
  points to the stack allocated `struct cpumask newmask` in
  `kvm_send_ipi_mask_allbutself`. The size of a `struct cpumask` is
  potentially large, as it's CONFIG_NR_CPUS divided by BITS_PER_LONG for
  the target architecture. CONFIG_NR_CPUS for X86_64 can be as high as
  8192, making a single instance of a `struct cpumask` 1024 B.

This patch fixes it by pre-allocate 1 cpumask variable per cpu and use it for
both pv tlb and pv ipis..

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:34:25 +01:00
Wanpeng Li
a262bca3ab KVM: Introduce pv check helpers
Introduce some pv check helpers for consistency.

Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:34:19 +01:00
Tony Luck
59b5809655 x86/mce: Fix logic and comments around MSR_PPIN_CTL
There are two implemented bits in the PPIN_CTL MSR:

Bit 0: LockOut (R/WO)
      Set 1 to prevent further writes to MSR_PPIN_CTL.

Bit 1: Enable_PPIN (R/W)
       If 1, enables MSR_PPIN to be accessible using RDMSR.
       If 0, an attempt to read MSR_PPIN will cause #GP.

So there are four defined values:
	0: PPIN is disabled, PPIN_CTL may be updated
	1: PPIN is disabled. PPIN_CTL is locked against updates
	2: PPIN is enabled. PPIN_CTL may be updated
	3: PPIN is enabled. PPIN_CTL is locked against updates

Code would only enable the X86_FEATURE_INTEL_PPIN feature for case "2".
When it should have done so for both case "2" and case "3".

Fix the final test to just check for the enable bit. Also fix some of
the other comments in this function.

Fixes: 3f5a7896a5 ("x86/mce: Include the PPIN in MCE records when available")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200226011737.9958-1-tony.luck@intel.com
2020-02-27 21:36:42 +01:00
Sean Christopherson
735a6dd022 x86/pkeys: Manually set X86_FEATURE_OSPKE to preserve existing changes
Explicitly set X86_FEATURE_OSPKE via set_cpu_cap() instead of calling
get_cpu_cap() to pull the feature bit from CPUID after enabling CR4.PKE.
Invoking get_cpu_cap() effectively wipes out any {set,clear}_cpu_cap()
changes that were made between this_cpu->c_init() and setup_pku(), as
all non-synthetic feature words are reinitialized from the CPU's CPUID
values.

Blasting away capability updates manifests most visibility when running
on a VMX capable CPU, but with VMX disabled by BIOS.  To indicate that
VMX is disabled, init_ia32_feat_ctl() clears X86_FEATURE_VMX, using
clear_cpu_cap() instead of setup_clear_cpu_cap() so that KVM can report
which CPU is misconfigured (KVM needs to probe every CPU anyways).
Restoring X86_FEATURE_VMX from CPUID causes KVM to think VMX is enabled,
ultimately leading to an unexpected #GP when KVM attempts to do VMXON.

Arguably, init_ia32_feat_ctl() should use setup_clear_cpu_cap() and let
KVM figure out a different way to report the misconfigured CPU, but VMX
is not the only feature bit that is affected, i.e. there is precedent
that tweaking feature bits via {set,clear}_cpu_cap() after ->c_init()
is expected to work.  Most notably, x86_init_rdrand()'s clearing of
X86_FEATURE_RDRAND when RDRAND malfunctions is also overwritten.

Fixes: 0697694564 ("x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU")
Reported-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200226231615.13664-1-sean.j.christopherson@intel.com
2020-02-27 19:02:45 +01:00
Andy Lutomirski
65c668f5fa x86/traps: Stop using ist_enter/exit() in do_int3()
#BP is not longer using IST and using ist_enter() and ist_exit() makes it
harder to change ist_enter() and ist_exit()'s behavior.  Instead open-code
the very small amount of required logic.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220217.150607679@linutronix.de
2020-02-27 15:28:39 +01:00
Thomas Gleixner
17dbedb5da x86/irq: Remove useless return value from do_IRQ()
Nothing is using it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.826870369@linutronix.de
2020-02-27 14:48:40 +01:00
Thomas Gleixner
d244d0e195 x86/traps: Document do_spurious_interrupt_bug()
Add a comment which explains why this empty handler for a reserved vector
exists.

Requested-by: Josh Poimboeuf <jpoimboe@redhat.com>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.624165786@linutronix.de
2020-02-27 14:48:40 +01:00
Thomas Gleixner
e039dd8159 x86/traps: Remove pointless irq enable from do_spurious_interrupt_bug()
That function returns immediately after conditionally reenabling interrupts which
is more than pointless and requires the ASM code to disable interrupts again.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20191023123117.871608831@linutronix.de
Link: https://lkml.kernel.org/r/20200225220216.518575042@linutronix.de
2020-02-27 14:48:39 +01:00
Thomas Gleixner
840371bea1 x86/entry/32: Force MCE through do_mce()
Remove the pointless difference between 32 and 64 bit to make further
unifications simpler.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.428188397@linutronix.de
2020-02-27 14:48:39 +01:00
Andy Lutomirski
55ba18d6ed x86/mce: Disable tracing and kprobes on do_machine_check()
do_machine_check() can be raised in almost any context including the most
fragile ones. Prevent kprobes and tracing.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200225220216.315548935@linutronix.de
2020-02-27 14:48:39 +01:00
Ingo Molnar
e9765680a3 EFI updates for v5.7:
This time, the set of changes for the EFI subsystem is much larger than
 usual. The main reasons are:
 - Get things cleaned up before EFI support for RISC-V arrives, which will
   increase the size of the validation matrix, and therefore the threshold to
   making drastic changes,
 - After years of defunct maintainership, the GRUB project has finally started
   to consider changes from the distros regarding UEFI boot, some of which are
   highly specific to the way x86 does UEFI secure boot and measured boot,
   based on knowledge of both shim internals and the layout of bootparams and
   the x86 setup header. Having this maintenance burden on other architectures
   (which don't need shim in the first place) is hard to justify, so instead,
   we are introducing a generic Linux/UEFI boot protocol.
 
 Summary of changes:
 - Boot time GDT handling changes (Arvind)
 - Simplify handling of EFI properties table on arm64
 - Generic EFI stub cleanups, to improve command line handling, file I/O,
   memory allocation, etc.
 - Introduce a generic initrd loading method based on calling back into
   the firmware, instead of relying on the x86 EFI handover protocol or
   device tree.
 - Introduce a mixed mode boot method that does not rely on the x86 EFI
   handover protocol either, and could potentially be adopted by other
   architectures (if another one ever surfaces where one execution mode
   is a superset of another)
 - Clean up the contents of struct efi, and move out everything that
   doesn't need to be stored there.
 - Incorporate support for UEFI spec v2.8A changes that permit firmware
   implementations to return EFI_UNSUPPORTED from UEFI runtime services at
   OS runtime, and expose a mask of which ones are supported or unsupported
   via a configuration table.
 - Various documentation updates and minor code cleanups (Heinrich)
 - Partial fix for the lack of by-VA cache maintenance in the decompressor
   on 32-bit ARM. Note that these patches were deliberately put at the
   beginning so they can be used as a stable branch that will be shared with
   a PR containing the complete fix, which I will send to the ARM tree.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEnNKg2mrY9zMBdeK7wjcgfpV0+n0FAl5S7WYACgkQwjcgfpV0
 +n1jmQgAmwV3V8pbgB4mi4P2Mv8w5Zj5feUe6uXnTR2AFv5nygLcTzdxN+TU/6lc
 OmZv2zzdsAscYlhuUdI/4t4cXIjHAZI39+UBoNRuMqKbkbvXCFscZANLxvJjHjZv
 FFbgUk0DXkF0BCEDuSLNavidAv4b3gZsOmHbPfwuB8xdP05LbvbS2mf+2tWVAi2z
 ULfua/0o9yiwl19jSS6iQEPCvvLBeBzTLW7x5Rcm/S0JnotzB59yMaeqD7jO8JYP
 5PvI4WM/l5UfVHnZp2k1R76AOjReALw8dQgqAsT79Q7+EH3sNNuIjU6omdy+DFf4
 tnpwYfeLOaZ1SztNNfU87Hsgnn2CGw==
 =pDE3
 -----END PGP SIGNATURE-----

Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core

Pull EFI updates for v5.7 from Ard Biesheuvel:

This time, the set of changes for the EFI subsystem is much larger than
usual. The main reasons are:

 - Get things cleaned up before EFI support for RISC-V arrives, which will
   increase the size of the validation matrix, and therefore the threshold to
   making drastic changes,

 - After years of defunct maintainership, the GRUB project has finally started
   to consider changes from the distros regarding UEFI boot, some of which are
   highly specific to the way x86 does UEFI secure boot and measured boot,
   based on knowledge of both shim internals and the layout of bootparams and
   the x86 setup header. Having this maintenance burden on other architectures
   (which don't need shim in the first place) is hard to justify, so instead,
   we are introducing a generic Linux/UEFI boot protocol.

Summary of changes:

 - Boot time GDT handling changes (Arvind)

 - Simplify handling of EFI properties table on arm64

 - Generic EFI stub cleanups, to improve command line handling, file I/O,
   memory allocation, etc.

 - Introduce a generic initrd loading method based on calling back into
   the firmware, instead of relying on the x86 EFI handover protocol or
   device tree.

 - Introduce a mixed mode boot method that does not rely on the x86 EFI
   handover protocol either, and could potentially be adopted by other
   architectures (if another one ever surfaces where one execution mode
   is a superset of another)

 - Clean up the contents of struct efi, and move out everything that
   doesn't need to be stored there.

 - Incorporate support for UEFI spec v2.8A changes that permit firmware
   implementations to return EFI_UNSUPPORTED from UEFI runtime services at
   OS runtime, and expose a mask of which ones are supported or unsupported
   via a configuration table.

 - Various documentation updates and minor code cleanups (Heinrich)

 - Partial fix for the lack of by-VA cache maintenance in the decompressor
   on 32-bit ARM. Note that these patches were deliberately put at the
   beginning so they can be used as a stable branch that will be shared with
   a PR containing the complete fix, which I will send to the ARM tree.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-02-26 15:21:22 +01:00
Thomas Gleixner
d364847eed x86/mce/therm_throt: Undo thermal polling properly on CPU offline
Chris Wilson reported splats from running the thermal throttling
workqueue callback on offlined CPUs. The problem is that that callback
should not even run on offlined CPUs but it happens nevertheless because
the offlining callback thermal_throttle_offline() does not symmetrically
undo the setup work done in its onlining counterpart. IOW,

 1. The thermal interrupt vector should be masked out before ...

 2. ... cancelling any pending work synchronously so that no new work is
 enqueued anymore.

Do those things and fix the issue properly.

 [ bp: Write commit message. ]

Fixes: f6656208f0 ("x86/mce/therm_throt: Optimize notifications of thermal throttle")
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Pandruvada, Srinivas <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/158120068234.18291.7938335950259651295@skylake-alporthouse-com
2020-02-25 21:21:44 +01:00
Arvind Sankar
6f8f0dc980 x86/vmlinux: Drop unneeded linker script discard of .eh_frame
Now that .eh_frame sections for the files in setup.elf and realmode.elf
are not generated anymore, the linker scripts don't need the special
output section name /DISCARD/ any more.

Remove the one in the main kernel linker script as well, since there are
no .eh_frame sections already, and fix up a comment referencing .eh_frame.

Update the comment in asm/dwarf2.h referring to .eh_frame so it continues
to make sense, as well as being more specific.

 [ bp: Touch up commit message. ]

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lkml.kernel.org/r/20200224232129.597160-3-nivedita@alum.mit.edu
2020-02-25 14:51:29 +01:00
Dave Hansen
16171bffc8 x86/pkeys: Add check for pkey "overflow"
Alex Shi reported the pkey macros above arch_set_user_pkey_access()
to be unused.  They are unused, and even refer to a nonexistent
CONFIG option.

But, they might have served a good use, which was to ensure that
the code does not try to set values that would not fit in the
PKRU register.  As it stands, a too-large 'pkey' value would
be likely to silently overflow the u32 new_pkru_bits.

Add a check to look for overflows.  Also add a comment to remind
any future developer to closely examine the types used to store
pkey values if arch_max_pkey() ever changes.

This boots and passes the x86 pkey selftests.

Reported-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200122165346.AD4DA150@viggo.jf.intel.com
2020-02-24 20:25:21 +01:00
Ingo Molnar
546121b65f Linux 5.6-rc3
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl5TFjYeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGikYIAIhI4C8R87wyj/0m
 b2NWk6TZ5AFmiZLYSbsPYxdSC9OLdUmlGFKgL2SyLTwZCiHChm+cNBrngp3hJ6gz
 x1YH99HdjzkiaLa0hCc2+a/aOt8azGU2RiWEP8rbo0gFSk28wE6FjtzSxR95jyPz
 FRKo/sM+dHBMFXrthJbr+xHZ1De28MITzS2ddstr/10ojoRgm43I3qo1JKhjoDN5
 9GGb6v0Md5eo+XZjjB50CvgF5GhpiqW7+HBB7npMsgTk37GdsR5RlosJ/TScLVC9
 dNeanuqk8bqMGM0u2DFYdDqjcqAlYbt8aobuWWCB5xgPBXr5G2nox+IgF/f9G6UH
 EShA/xs=
 =OFPc
 -----END PGP SIGNATURE-----

Merge tag 'v5.6-rc3' into sched/core, to pick up fixes and dependent patches

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-02-24 11:36:09 +01:00
Ard Biesheuvel
9a440391b5 x86/ima: Use EFI GetVariable only when available
Replace the EFI runtime services check with one that tells us whether
EFI GetVariable() is implemented by the firmware.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Ard Biesheuvel
59f2a619a2 efi: Add 'runtime' pointer to struct efi
Instead of going through the EFI system table each time, just copy the
runtime services table pointer into struct efi directly. This is the
last use of the system table pointer in struct efi, allowing us to
drop it in a future patch, along with a fair amount of quirky handling
of the translated address.

Note that usually, the runtime services pointer changes value during
the call to SetVirtualAddressMap(), so grab the updated value as soon
as that call returns. (Mixed mode uses a 1:1 mapping, and kexec boot
enters with the updated address in the system table, so in those cases,
we don't need to do anything here)

Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Ard Biesheuvel
9cd437ac0e efi/x86: Make fw_vendor, config_table and runtime sysfs nodes x86 specific
There is some code that exposes physical addresses of certain parts of
the EFI firmware implementation via sysfs nodes. These nodes are only
used on x86, and are of dubious value to begin with, so let's move
their handling into the x86 arch code.

Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Ard Biesheuvel
0a67361dcd efi/x86: Remove runtime table address from kexec EFI setup data
Since commit 33b85447fa ("efi/x86: Drop two near identical versions
of efi_runtime_init()"), we no longer map the EFI runtime services table
before calling SetVirtualAddressMap(), which means we don't need the 1:1
mapped physical address of this table, and so there is no point in passing
the address via EFI setup data on kexec boot.

Note that the kexec tools will still look for this address in sysfs, so
we still need to provide it.

Tested-by: Tony Luck <tony.luck@intel.com> # arch/ia64
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23 21:59:42 +01:00
Linus Torvalds
dca132a60f Two fixes for the AMD MCE driver:
- Populate the per CPU MCA bank descriptor pointer only after it has been
     completely set up to prevent a use-after-free in case that one of the
     subsequent initialization step fails
 
   - Implement a proper release function for the sysfs entries of MCA
     threshold controls instead of freeing the memory right in the CPU
     teardown code, which leads to another use-after-free when the
     associated sysfs file is opened and accessed.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl5RkwATHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoY6ED/4oafN9DmeY18oUv1QpoMQQMa6iduz6
 udemhpjqVXO7R1Ste4ccM/fIQ8sMjf58isuxUClcDwrX3fxv+lusK2iVPEw99Vpo
 w1xSjdXNW0KSSiQko9oMHVu+xcXIt8vxpL4YyjEuR81rcoecFaq2c2KhLMAW4o0p
 3mEv7/QYPfpKc4ydcbcHo2JF6U1sfUpsWpoe/SxpXRpxeoy64baCWZGbcsUXqjB6
 3MRxxy+ypKKKPPUM1py4D/ViDXwkhhP+gMD4ljWXCprpul/KuXAMEgvW39MtVsBJ
 uMF3PMXqjKx+WY492tpxtdZjWej+X13ID/cTc2w1EBHz30Qxmc6RieTKi6FzsJYB
 PKsTWdGarzORioaBg51Riq27C3+fjHbe6WqkhIQzmenSIwiV1o6o4IyuOs5sdlxX
 rjIk/ssNeAxRpCy308i6Vaq98PBZqAY1/iUZN50vAzldH3bwKxobowjn+AYStA0c
 9BF5zw7/3oXB4WaByuBwJ3DzWjqiXM4EUPu7LYF9DVSvj+A2xOmhwN+uz3SK6hBk
 vkxiFE50Lo2qoDaATJozY8+nxgUKRNiDdz+udhVsoQxNKWUMxirsH18TFu8yBl2r
 HGKsfCBY4CnV64WRy5IKQsqt3EhAgAUUoD0jSy7P3xf4HwSKAn/9OZ1cWQAo1wzQ
 xnXUtRDFc7ScHg==
 =2f84
 -----END PGP SIGNATURE-----

Merge tag 'ras-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS fixes from Thomas Gleixner:
 "Two fixes for the AMD MCE driver:

   - Populate the per CPU MCA bank descriptor pointer only after it has
     been completely set up to prevent a use-after-free in case that one
     of the subsequent initialization step fails

   - Implement a proper release function for the sysfs entries of MCA
     threshold controls instead of freeing the memory right in the CPU
     teardown code, which leads to another use-after-free when the
     associated sysfs file is opened and accessed"

* tag 'ras-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/amd: Fix kobject lifetime
  x86/mce/amd: Publish the bank pointer only after setup has succeeded
2020-02-22 18:02:10 -08:00
Linus Torvalds
fca1037864 Two fixes for x86:
- Remove the __force_oder definiton from the kaslr boot code as it is
     already defined in the page table code which makes GCC 10 builds fail
     because it changed the default to -fno-common.
 
   - Address the AMD erratum 1054 concerning the IRPERF capability and
     enable the Instructions Retired fixed counter on machines which are not
     affected by the erratum.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl5RlXkTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoV6vEACsB5d8TC+OYYn1UsRJZszQ4ItRoT2Q
 t++G1RjY+hIiEVb4BufhWi3DBsS2XETwO7LIma8tj+Vt/hhAs+3PyBiumFIz3HEN
 pJzPR7CszD6EiO0qRw5Mrj2n+EC8I1Ts/hKuzir0kQr0h+jxg3OAOWMnUNfXiqS2
 mGh3baMeNYvLvI/MUDBcFP0ZDMcgsYPb3qt4Qodg9bS31+d7xlTPwK6Lua5R8eih
 ZTaVOR2JMYXIYDQA5eAqB2P/GiFBDERQHrJUQ44mY9A14w3T7qjthfMiCAvWlVd7
 +ibxYA3/xujQumhyCFXmdxYEzyVzp8kLSlF7ERGVCdDZ20ZV/FA/c6uyUiW+tmUi
 NR915G8632qKF7TXRPITZaWl8rC0KEcm5W+K0uf8ThJKUdq5vigXURLV9t9udeKY
 HqQtyuNtesmKycF9oXG6OfFeKuveZR6XSlhLK2fMs/mxa9yyvyRyXNmwwATgTSI4
 RPwrpAB52snexARBR/kZ9p/kgB47FceVYOYuQMvcp/n+1KXNesmAIeT29vNSzYUK
 vL0M5XVBsz9pvTkQlhxW36sO8uLZG6SPZ+e0ypDt9YDz+YTXbBM91buxpYE9xk36
 2j0aPrexC6FwCEny9uEckHRuLUip2mpld4QOxH8j3itYme3LfPa1poajAoKBwFkg
 gu42lzbWqVArZA==
 =Pgxk
 -----END PGP SIGNATURE-----

Merge tag 'x86-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for x86:

   - Remove the __force_oder definiton from the kaslr boot code as it is
     already defined in the page table code which makes GCC 10 builds
     fail because it changed the default to -fno-common.

   - Address the AMD erratum 1054 concerning the IRPERF capability and
     enable the Instructions Retired fixed counter on machines which are
     not affected by the erratum"

* tag 'x86-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF
  x86/boot/compressed: Don't declare __force_order in kaslr_64.c
2020-02-22 17:08:16 -08:00
Arvind Sankar
67a6af7ad1 x86/boot: Remove KEEP_SEGMENTS support
Commit a24e785111 ("i386: paravirt boot sequence") added this flag for
use by paravirtualized environments such as Xen. However, Xen never made
use of this flag [1], and it was only ever used by lguest [2].

Commit ecda85e702 ("x86/lguest: Remove lguest support") removed
lguest, so KEEP_SEGMENTS has lost its last user.

[1] https://lore.kernel.org/lkml/4D4B097C.5050405@goop.org
[2] https://www.mail-archive.com/lguest@lists.ozlabs.org/msg00469.html

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200202171353.3736319-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22 23:37:37 +01:00
Peter Zijlstra (Intel)
6650cdd9a8 x86/split_lock: Enable split lock detection by kernel
A split-lock occurs when an atomic instruction operates on data that spans
two cache lines. In order to maintain atomicity the core takes a global bus
lock.

This is typically >1000 cycles slower than an atomic operation within a
cache line. It also disrupts performance on other cores (which must wait
for the bus lock to be released before their memory operations can
complete). For real-time systems this may mean missing deadlines. For other
systems it may just be very annoying.

Some CPUs have the capability to raise an #AC trap when a split lock is
attempted.

Provide a command line option to give the user choices on how to handle
this:

split_lock_detect=
	off	- not enabled (no traps for split locks)
	warn	- warn once when an application does a
		  split lock, but allow it to continue
		  running.
	fatal	- Send SIGBUS to applications that cause split lock

On systems that support split lock detection the default is "warn". Note
that if the kernel hits a split lock in any mode other than "off" it will
OOPs.

One implementation wrinkle is that the MSR to control the split lock
detection is per-core, not per thread. This might result in some short
lived races on HT systems in "warn" mode if Linux tries to enable on one
thread while disabling on the other. Race analysis by Sean Christopherson:

  - Toggling of split-lock is only done in "warn" mode.  Worst case
    scenario of a race is that a misbehaving task will generate multiple
    #AC exceptions on the same instruction.  And this race will only occur
    if both siblings are running tasks that generate split-lock #ACs, e.g.
    a race where sibling threads are writing different values will only
    occur if CPUx is disabling split-lock after an #AC and CPUy is
    re-enabling split-lock after *its* previous task generated an #AC.
  - Transitioning between off/warn/fatal modes at runtime isn't supported
    and disabling is tracked per task, so hardware will always reach a steady
    state that matches the configured mode.  I.e. split-lock is guaranteed to
    be enabled in hardware once all _TIF_SLD threads have been scheduled out.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200126200535.GB30377@agluck-desk2.amr.corp.intel.com
2020-02-20 21:17:53 +01:00
Kim Phillips
21b5ee59ef x86/cpu/amd: Enable the fixed Instructions Retired counter IRPERF
Commit

  aaf248848d ("perf/x86/msr: Add AMD IRPERF (Instructions Retired)
		  performance counter")

added support for access to the free-running counter via 'perf -e
msr/irperf/', but when exercised, it always returns a 0 count:

BEFORE:

  $ perf stat -e instructions,msr/irperf/ true

   Performance counter stats for 'true':

             624,833      instructions
                   0      msr/irperf/

Simply set its enable bit - HWCR bit 30 - to make it start counting.

Enablement is restricted to all machines advertising IRPERF capability,
except those susceptible to an erratum that makes the IRPERF return
bad values.

That erratum occurs in Family 17h models 00-1fh [1], but not in F17h
models 20h and above [2].

AFTER (on a family 17h model 31h machine):

  $ perf stat -e instructions,msr/irperf/ true

   Performance counter stats for 'true':

             621,690      instructions
             622,490      msr/irperf/

[1] Revision Guide for AMD Family 17h Models 00h-0Fh Processors
[2] Revision Guide for AMD Family 17h Models 30h-3Fh Processors

The revision guides are available from the bugzilla Link below.

 [ bp: Massage commit message. ]

Fixes: aaf248848d ("perf/x86/msr: Add AMD IRPERF (Instructions Retired) performance counter")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
Link: http://lkml.kernel.org/r/20200214201805.13830-1-kim.phillips@amd.com
2020-02-19 20:01:54 +01:00
Prarit Bhargava
2976908e41 x86/mce: Do not log spurious corrected mce errors
A user has reported that they are seeing spurious corrected errors on
their hardware.

Intel Errata HSD131, HSM142, HSW131, and BDM48 report that "spurious
corrected errors may be logged in the IA32_MC0_STATUS register with
the valid field (bit 63) set, the uncorrected error field (bit 61) not
set, a Model Specific Error Code (bits [31:16]) of 0x000F, and an MCA
Error Code (bits [15:0]) of 0x0005." The Errata PDFs are linked in the
bugzilla below.

Block these spurious errors from the console and logs.

 [ bp: Move the intel_filter_mce() header declarations into the already
   existing CONFIG_X86_MCE_INTEL ifdeffery. ]

Co-developed-by: Alexander Krupp <centos@akr.yagii.de>
Signed-off-by: Alexander Krupp <centos@akr.yagii.de>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206587
Link: https://lkml.kernel.org/r/20200219131611.36816-1-prarit@redhat.com
2020-02-19 18:14:49 +01:00
Benjamin Thiel
b10c307f6f x86/cpu: Move prototype for get_umwait_control_msr() to a global location
.. in order to fix a -Wmissing-prototypes warning.

No functional change.

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: kvm@vger.kernel.org
Link: https://lkml.kernel.org/r/20200123172945.7235-1-b.thiel@posteo.de
2020-02-17 19:32:45 +01:00
Benjamin Thiel
cdcb58cc05 x86/iopl: Include prototype header for ksys_ioperm()
.. in order to fix a -Wmissing-prototype warning.

No functional change.

Signed-off-by: Benjamin Thiel <b.thiel@posteo.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200123133051.5974-1-b.thiel@posteo.de
2020-02-17 16:36:53 +01:00
Thomas Gleixner
b95a8a27c3 x86/vdso: Use generic VDSO clock mode storage
Switch to the generic VDSO clock mode storage.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts)
Acked-by: Juergen Gross <jgross@suse.com> (Xen parts)
Acked-by: Paolo Bonzini <pbonzini@redhat.com> (KVM parts)
Link: https://lkml.kernel.org/r/20200207124403.152039903@linutronix.de
2020-02-17 14:40:23 +01:00
Thomas Gleixner
eec399dd86 x86/vdso: Move VDSO clocksource state tracking to callback
All architectures which use the generic VDSO code have their own storage
for the VDSO clock mode. That's pointless and just requires duplicate code.

X86 abuses the function which retrieves the architecture specific clock
mode storage to mark the clocksource as used in the VDSO. That's silly
because this is invoked on every tick when the VDSO data is updated.

Move this functionality to the clocksource::enable() callback so it gets
invoked once when the clocksource is installed. This allows to make the
clock mode storage generic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>  (Hyper-V parts)
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts)
Acked-by: Juergen Gross <jgross@suse.com> (Xen parts)
Link: https://lkml.kernel.org/r/20200207124402.934519777@linutronix.de
2020-02-17 14:40:22 +01:00
Martin Molnar
4d1d0977a2 x86: Fix a handful of typos
Fix a couple of typos in code comments.

 [ bp: While at it: s/IRQ's/IRQs/. ]

Signed-off-by: Martin Molnar <martin.molnar.programming@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/0819a044-c360-44a4-f0b6-3f5bafe2d35c@gmail.com
2020-02-16 20:58:06 +01:00
Al Viro
c8e3dd8660 x86 user stack frame reads: switch to explicit __get_user()
rather than relying upon the magic in raw_copy_from_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-15 17:26:26 -05:00
Thomas Gleixner
51dede9c05 x86/mce/amd: Fix kobject lifetime
Accessing the MCA thresholding controls in sysfs concurrently with CPU
hotplug can lead to a couple of KASAN-reported issues:

  BUG: KASAN: use-after-free in sysfs_file_ops+0x155/0x180
  Read of size 8 at addr ffff888367578940 by task grep/4019

and

  BUG: KASAN: use-after-free in show_error_count+0x15c/0x180
  Read of size 2 at addr ffff888368a05514 by task grep/4454

for example. Both result from the fact that the threshold block
creation/teardown code frees the descriptor memory itself instead of
defining proper ->release function and leaving it to the driver core to
take care of that, after all sysfs accesses have completed.

Do that and get rid of the custom freeing code, fixing the above UAFs in
the process.

  [ bp: write commit message. ]

Fixes: 9526866439 ("[PATCH] x86_64: mce_amd support for family 0x10 processors")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200214082801.13836-1-bp@alien8.de
2020-02-14 09:28:31 +01:00
Borislav Petkov
6e5cf31fbe x86/mce/amd: Publish the bank pointer only after setup has succeeded
threshold_create_bank() creates a bank descriptor per MCA error
thresholding counter which can be controlled over sysfs. It publishes
the pointer to that bank in a per-CPU variable and then goes on to
create additional thresholding blocks if the bank has such.

However, that creation of additional blocks in
allocate_threshold_blocks() can fail, leading to a use-after-free
through the per-CPU pointer.

Therefore, publish that pointer only after all blocks have been setup
successfully.

Fixes: 019f34fccf ("x86, MCE, AMD: Move shared bank to node descriptor")
Reported-by: Saar Amar <Saar.Amar@microsoft.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200128140846.phctkvx5btiexvbx@kili.mountain
2020-02-13 18:58:39 +01:00
Yu-cheng Yu
e70b100806 x86/fpu/xstate: Warn when checking alignment of disabled xfeatures
An XSAVES component's alignment/offset is meaningful only when the
feature is enabled. Return zero and WARN_ONCE on checking alignment of
disabled features.

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200109211452.27369-4-yu-cheng.yu@intel.com
2020-02-12 15:43:34 +01:00
Yu-cheng Yu
49a91d61ae x86/fpu/xstate: Fix XSAVES offsets in setup_xstate_comp()
In setup_xstate_comp(), each XSAVES component offset starts from the
end of its preceding component plus alignment. A disabled feature does
not take space and its offset should be set to the end of its preceding
one with no alignment. However, in this case, alignment is incorrectly
added to the offset, which can cause the next component to have a wrong
offset.

This problem has not been visible because currently there is no xfeature
requiring alignment.

Fix it by tracking the next starting offset only from enabled
xfeatures. To make it clear, also change the function name to
setup_xstate_comp_offsets().

 [ bp: Fix a typo in the comment above it, while at it. ]

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200109211452.27369-3-yu-cheng.yu@intel.com
2020-02-12 15:43:31 +01:00
Ard Biesheuvel
ff5ac61ee8 x86/ima: use correct identifier for SetupMode variable
The IMA arch code attempts to inspect the "SetupMode" EFI variable
by populating a variable called efi_SetupMode_name with the string
"SecureBoot" and passing that to the EFI GetVariable service, which
obviously does not yield the expected result.

Given that the string is only referenced a single time, let's get
rid of the intermediate variable, and pass the correct string as
an immediate argument. While at it, do the same for "SecureBoot".

Fixes: 399574c64e ("x86/ima: retry detecting secure boot mode")
Fixes: 980ef4d22a ("x86/ima: check EFI SetupMode too")
Cc: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org # v5.3
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-11 14:42:37 -05:00
Yu-cheng Yu
c12e13dcd8 x86/fpu/xstate: Fix last_good_offset in setup_xstate_features()
The function setup_xstate_features() uses CPUID to find each xfeature's
standard-format offset and size.  Since XSAVES always uses the compacted
format, supervisor xstates are *NEVER* in the standard-format and their
offsets are left as -1's.  However, they are still being tracked as
last_good_offset.

Fix it by tracking only user xstate offsets.

 [ bp: Use xfeature_is_supervisor() and save an indentation level. Drop
   now unused xfeature_is_user(). ]

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20200109211452.27369-2-yu-cheng.yu@intel.com
2020-02-11 19:54:04 +01:00
Linus Torvalds
1a2a76c268 A set of fixes for X86:
- Ensure that the PIT is set up when the local APIC is disable or
    configured in legacy mode. This is caused by an ordering issue
    introduced in the recent changes which skip PIT initialization when the
    TSC and APIC frequencies are already known.
 
  - Handle malformed SRAT tables during early ACPI parsing which caused an
    infinite loop anda boot hang.
 
  - Fix a long standing race in the affinity setting code which affects PCI
    devices with non-maskable MSI interrupts. The problem is caused by the
    non-atomic writes of the MSI address (destination APIC id) and data
    (vector) fields which the device uses to construct the MSI message. The
    non-atomic writes are mandated by PCI.
 
    If both fields change and the device raises an interrupt after writing
    address and before writing data, then the MSI block constructs a
    inconsistent message which causes interrupts to be lost and subsequent
    malfunction of the device.
 
    The fix is to redirect the interrupt to the new vector on the current
    CPU first and then switch it over to the new target CPU. This allows to
    observe an eventually raised interrupt in the transitional stage (old
    CPU, new vector) to be observed in the APIC IRR and retriggered on the
    new target CPU and the new vector. The potential spurious interrupts
    caused by this are harmless and can in the worst case expose a buggy
    driver (all handlers have to be able to deal with spurious interrupts as
    they can and do happen for various reasons).
 
  - Add the missing suspend/resume mechanism for the HYPERV hypercall page
    which prevents resume hibernation on HYPERV guests. This change got
    lost before the merge window.
 
  - Mask the IOAPIC before disabling the local APIC to prevent potentially
    stale IOAPIC remote IRR bits which cause stale interrupt lines after
    resume.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl5AEJwTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoWY2D/47ur9gsVQGryKzneVAr0SCsq4Un11e
 uifX4ldu4gCEBRTYhpgcpiFKeLvY/QJ6uOD+gQUHyy/s+lCf6yzE6UhXEqSCtcT7
 LkSxD8jAFf6KhMA6iqYBfyxUsPMXBetLjjHWsyc/kf15O/vbYm7qf05timmNZkDS
 S7C+yr3KRqRjLR7G7t4twlgC9aLcNUQihUdsH2qyTvjnlkYHJLDa0/Js7bFYYKVx
 9GdUDLvPFB1mZ76g012De4R3kJsWitiyLlQ38DP5VysKulnszUCdiXlgCEFrgxvQ
 OQhLafQzOAzvxQmP+1alODR0dmJZA8k0zsDeeTB/vTpRvv6+Pe2qUswLSpauBzuq
 TpDsrv8/5pwZh28+91f/Unk+tH8NaVNtGe/Uf+ePxIkn1nbqL84o4NHGplM6R97d
 HAWdZQZ1cGRLf6YRRJ+57oM/5xE3vBbF1Wn0+QDTFwdsk2vcxuQ4eB3M/8E1V7Zk
 upp8ty50bZ5+rxQ8XTq/eb8epSRnfLoBYpi4ux6MIOWRdmKDl40cDeZCzA2kNP7m
 qY1haaRN3ksqvhzc0Yf6cL+CgvC4ur8gRHezfOqmBzVoaLyVEFIVjgjR/ojf0bq8
 /v+L9D5+IdIv4jEZruRRs0gOXNDzoBbvf0qKGaO0tUTWiDsv7c5AGixp8aozniHS
 HXsv1lIpRuC7WQ==
 =WxKD
 -----END PGP SIGNATURE-----

Merge tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A set of fixes for X86:

   - Ensure that the PIT is set up when the local APIC is disable or
     configured in legacy mode. This is caused by an ordering issue
     introduced in the recent changes which skip PIT initialization when
     the TSC and APIC frequencies are already known.

   - Handle malformed SRAT tables during early ACPI parsing which caused
     an infinite loop anda boot hang.

   - Fix a long standing race in the affinity setting code which affects
     PCI devices with non-maskable MSI interrupts. The problem is caused
     by the non-atomic writes of the MSI address (destination APIC id)
     and data (vector) fields which the device uses to construct the MSI
     message. The non-atomic writes are mandated by PCI.

     If both fields change and the device raises an interrupt after
     writing address and before writing data, then the MSI block
     constructs a inconsistent message which causes interrupts to be
     lost and subsequent malfunction of the device.

     The fix is to redirect the interrupt to the new vector on the
     current CPU first and then switch it over to the new target CPU.
     This allows to observe an eventually raised interrupt in the
     transitional stage (old CPU, new vector) to be observed in the APIC
     IRR and retriggered on the new target CPU and the new vector.

     The potential spurious interrupts caused by this are harmless and
     can in the worst case expose a buggy driver (all handlers have to
     be able to deal with spurious interrupts as they can and do happen
     for various reasons).

   - Add the missing suspend/resume mechanism for the HYPERV hypercall
     page which prevents resume hibernation on HYPERV guests. This
     change got lost before the merge window.

   - Mask the IOAPIC before disabling the local APIC to prevent
     potentially stale IOAPIC remote IRR bits which cause stale
     interrupt lines after resume"

* tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Mask IOAPIC entries when disabling the local APIC
  x86/hyperv: Suspend/resume the hypercall page for hibernation
  x86/apic/msi: Plug non-maskable MSI affinity race
  x86/boot: Handle malformed SRAT tables during early ACPI parsing
  x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
2020-02-09 12:11:12 -08:00
Linus Torvalds
c9d35ee049 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...
2020-02-08 13:26:41 -08:00
Al Viro
d7167b1499 fs_parse: fold fs_parameter_desc/fs_parameter_spec
The former contains nothing but a pointer to an array of the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:37 -05:00
Eric Sandeen
96cafb9ccb fs_parser: remove fs_parameter_description name field
Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:36 -05:00
Tony W Wang-oc
0f378d73d4 x86/apic: Mask IOAPIC entries when disabling the local APIC
When a system suspends, the local APIC is disabled in the suspend sequence,
but the IOAPIC is left in the current state. This means unmasked interrupt
lines stay unmasked. This is usually the case for IOAPIC pin 9 to which the
ACPI interrupt is connected.

That means that in suspended state the IOAPIC can respond to an external
interrupt, e.g. the wakeup via keyboard/RTC/ACPI, but the interrupt message
cannot be handled by the disabled local APIC. As a consequence the Remote
IRR bit is set, but the local APIC does not send an EOI to acknowledge
it. This causes the affected interrupt line to become stale and the stale
Remote IRR bit will cause a hang when __synchronize_hardirq() is invoked
for that interrupt line.

To prevent this, mask all IOAPIC entries before disabling the local
APIC. The resume code already has the unmask operation inside.

[ tglx: Massaged changelog ]

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1579076539-7267-1-git-send-email-TonyWWang-oc@zhaoxin.com
2020-02-07 15:32:16 +01:00
Linus Torvalds
90568ecf56 s390:
* fix register corruption
 * ENOTSUPP/EOPNOTSUPP mixed
 * reset cleanups/fixes
 * selftests
 
 x86:
 * Bug fixes and cleanups
 * AMD support for APIC virtualization even in combination with
   in-kernel PIT or IOAPIC.
 
 MIPS:
 * Compilation fix.
 
 Generic:
 * Fix refcount overflow for zero page.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJeOuf7AAoJEL/70l94x66DOBQH/j1W9lUpbDgr9aWbrZT+O/yP
 FWzUDrRlCZCjV1FQKbGPa4YLeDRTG5n+RIQTjmCGRqiMqeoELSJ1+iK99e97nG/u
 L28zf/90Nf0R+wwHL4AOFeploTYfG4WP8EVnlr3CG2UCJrNjxN1KU7yRZoWmWa2d
 ckLJ8ouwNvx6VZd233LVmT38EP4352d1LyqIL8/+oXDIyAcRJLFQu1gRCwagsh3w
 1v1czowFpWnRQ/z9zU7YD+PA4v85/Ge8sVVHlpi1X5NgV/khk4U6B0crAw6M+la+
 mTmpz9g56oAh9m9NUdtv4zDCz1EWGH0v8+ZkAajUKtrM0ftJMn57P6p8PH4VVlE=
 =5+Wl
 -----END PGP SIGNATURE-----

Merge tag 'kvm-5.6-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more KVM updates from Paolo Bonzini:
 "s390:
   - fix register corruption
   - ENOTSUPP/EOPNOTSUPP mixed
   - reset cleanups/fixes
   - selftests

  x86:
   - Bug fixes and cleanups
   - AMD support for APIC virtualization even in combination with
     in-kernel PIT or IOAPIC.

  MIPS:
   - Compilation fix.

  Generic:
   - Fix refcount overflow for zero page"

* tag 'kvm-5.6-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
  KVM: vmx: delete meaningless vmx_decache_cr0_guest_bits() declaration
  KVM: x86: Mark CR4.UMIP as reserved based on associated CPUID bit
  x86: vmxfeatures: rename features for consistency with KVM and manual
  KVM: SVM: relax conditions for allowing MSR_IA32_SPEC_CTRL accesses
  KVM: x86: Fix perfctr WRMSR for running counters
  x86/kvm/hyper-v: don't allow to turn on unsupported VMX controls for nested guests
  x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()
  kvm: mmu: Separate generating and setting mmio ptes
  kvm: mmu: Replace unsigned with unsigned int for PTE access
  KVM: nVMX: Remove stale comment from nested_vmx_load_cr3()
  KVM: MIPS: Fold comparecount_func() into comparecount_wakeup()
  KVM: MIPS: Fix a build error due to referencing not-yet-defined function
  x86/kvm: do not setup pv tlb flush when not paravirtualized
  KVM: fix overflow of zero page refcount with ksm running
  KVM: x86: Take a u64 when checking for a valid dr7 value
  KVM: x86: use raw clock values consistently
  KVM: x86: reorganize pvclock_gtod_data members
  KVM: nVMX: delete meaningless nested_vmx_run() declaration
  KVM: SVM: allow AVIC without split irqchip
  kvm: ioapic: Lazy update IOAPIC EOI
  ...
2020-02-06 09:07:45 -08:00
Thadeu Lima de Souza Cascardo
64b38bd190 x86/kvm: do not setup pv tlb flush when not paravirtualized
kvm_setup_pv_tlb_flush will waste memory and print a misguiding message
when KVM paravirtualization is not available.

Intel SDM says that the when cpuid is used with EAX higher than the
maximum supported value for basic of extended function, the data for the
highest supported basic function will be returned.

So, in some systems, kvm_arch_para_features will return bogus data,
causing kvm_setup_pv_tlb_flush to detect support for pv tlb flush.

Testing for kvm_para_available will work as it checks for the hypervisor
signature.

Besides, when the "nopv" command line parameter is used, it should not
continue as well, as kvm_guest_init will no be called in that case.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-05 15:28:07 +01:00
Alexey Dobriyan
97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Thomas Gleixner
6f1a4891a5 x86/apic/msi: Plug non-maskable MSI affinity race
Evan tracked down a subtle race between the update of the MSI message and
the device raising an interrupt internally on PCI devices which do not
support MSI masking. The update of the MSI message is non-atomic and
consists of either 2 or 3 sequential 32bit wide writes to the PCI config
space.

   - Write address low 32bits
   - Write address high 32bits (If supported by device)
   - Write data

When an interrupt is migrated then both address and data might change, so
the kernel attempts to mask the MSI interrupt first. But for MSI masking is
optional, so there exist devices which do not provide it. That means that
if the device raises an interrupt internally between the writes then a MSI
message is sent built from half updated state.

On x86 this can lead to spurious interrupts on the wrong interrupt
vector when the affinity setting changes both address and data. As a
consequence the device interrupt can be lost causing the device to
become stuck or malfunctioning.

Evan tried to handle that by disabling MSI accross an MSI message
update. That's not feasible because disabling MSI has issues on its own:

 If MSI is disabled the PCI device is routing an interrupt to the legacy
 INTx mechanism. The INTx delivery can be disabled, but the disablement is
 not working on all devices.

 Some devices lose interrupts when both MSI and INTx delivery are disabled.

Another way to solve this would be to enforce the allocation of the same
vector on all CPUs in the system for this kind of screwed devices. That
could be done, but it would bring back the vector space exhaustion problems
which got solved a few years ago.

Fortunately the high address (if supported by the device) is only relevant
when X2APIC is enabled which implies interrupt remapping. In the interrupt
remapping case the affinity setting is happening at the interrupt remapping
unit and the PCI MSI message is programmed only once when the PCI device is
initialized.

That makes it possible to solve it with a two step update:

  1) Target the MSI msg to the new vector on the current target CPU

  2) Target the MSI msg to the new vector on the new target CPU

In both cases writing the MSI message is only changing a single 32bit word
which prevents the issue of inconsistency.

After writing the final destination it is necessary to check whether the
device issued an interrupt while the intermediate state #1 (new vector,
current CPU) was in effect.

This is possible because the affinity change is always happening on the
current target CPU. The code runs with interrupts disabled, so the
interrupt can be detected by checking the IRR of the local APIC. If the
vector is pending in the IRR then the interrupt is retriggered on the new
target CPU by sending an IPI for the associated vector on the target CPU.

This can cause spurious interrupts on both the local and the new target
CPU.

 1) If the new vector is not in use on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then interrupt entry code will
    ignore that spurious interrupt. The vector is marked so that the
    'No irq handler for vector' warning is supressed once.

 2) If the new vector is in use already on the local CPU then the IRR check
    might see an pending interrupt from the device which is using this
    vector. The IPI to the new target CPU will then invoke the handler of
    the device, which got the affinity change, even if that device did not
    issue an interrupt

 3) If the new vector is in use already on the local CPU and the device
    affected by the affinity change raised an interrupt during the
    transitional state (step #1 above) then the handler of the device which
    uses that vector on the local CPU will be invoked.

expose issues in device driver interrupt handlers which are not prepared to
handle a spurious interrupt correctly. This not a regression, it's just
exposing something which was already broken as spurious interrupts can
happen for a lot of reasons and all driver handlers need to be able to deal
with them.

Reported-by: Evan Green <evgreen@chromium.org>
Debugged-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Evan Green <evgreen@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
2020-02-01 09:31:47 +01:00
Linus Torvalds
b70a2d6b29 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - three fixes and a cleanup for the resctrl code

   - a HyperV fix

   - a fix to /proc/kcore contents in live debugging sessions

   - a fix for the x86 decoder opcode map"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/decoder: Add TEST opcode to Group3-2
  x86/resctrl: Clean up unused function parameter in mkdir path
  x86/resctrl: Fix a deadlock due to inaccurate reference
  x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup
  x86/resctrl: Fix use-after-free when deleting resource groups
  x86/hyper-v: Add "polling" bit to hv_synic_sint
  x86/crash: Define arch_crash_save_vmcoreinfo() if CONFIG_CRASH_CORE=y
2020-01-31 11:05:33 -08:00
Linus Torvalds
ccaaaf6fe5 MPX requires recompiling applications, which requires compiler support.
Unfortunately, GCC 9.1 is expected to be be released without support for
 MPX.  This means that there was only a relatively small window where
 folks could have ever used MPX.  It failed to gain wide adoption in the
 industry, and Linux was the only mainstream OS to ever support it widely.
 
 Support for the feature may also disappear on future processors.
 
 This set completes the process that we started during the 5.4 merge window.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABCAAGBQJeK1/pAAoJEGg1lTBwyZKwgC8QAIiVn1d7A9Uj/WpnpgfCChCZ
 9XiV6Ak999qD9fbAcrgNfPjieaD4mtokocSRVJuRgJu5iLnIJCINlozLPe4yVl7P
 7zebnxkLq0CIA8d56bEUoFlC0J+oWYlDVQePZzNQsSk5KHVGXVLpF6U4vDVzZeQy
 cprgvdeY+ehB7G6IIo0MWTg5ylKYAsOAyVvK8NIGpKY2k6/YqCnsptnsVE7bvlHy
 TrEOiUWLv+hh0bMkZdP1PwKQKEuMO/IZly0HtviFbMN7T4TB1spfg7ELoBucEq3T
 s4EVbYRe+nIE4tuEAveaX3CgxJek8cY5MlticskdaKSEACBwabdOF55qsZy0u+WA
 PYC4iUIXfbOH8OgieKWtGX4IuSkRYdQ2nP4BOpe4ZX4+zvU7zOCIyVSKRrwkX8cc
 ADtWI5FAtB36KCgUuWnHGHNZpOxPTbTLBuBataFY4Q2uBNJEBJpscZ5H9ObtyGFU
 ZjlzqFnM0nFNDKEI1EEtv9jLzgZTU1RQ46s7EFeSeEQ2/s9wJ3+s5sBlVbljsmus
 o658bLOEaRWC/aF15dgmEXW9GAO6uifNdmbzGnRn7oEMYyFQPTWbZvi1zGz58QaG
 Y6WTtigVtsSrHS4wpYd+p+n1W06VnB6J3BpBM4G1VQv1Vm0dNd1tUOfkqOzPjg7c
 33Itmsz2LaW1mb67GlgZ
 =g4cC
 -----END PGP SIGNATURE-----

Merge tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx

Pull x86 MPX removal from Dave Hansen:
 "MPX requires recompiling applications, which requires compiler
  support. Unfortunately, GCC 9.1 is expected to be be released without
  support for MPX. This means that there was only a relatively small
  window where folks could have ever used MPX. It failed to gain wide
  adoption in the industry, and Linux was the only mainstream OS to ever
  support it widely.

  Support for the feature may also disappear on future processors.

  This set completes the process that we started during the 5.4 merge
  window when the MPX prctl()s were removed. XSAVE support is left in
  place, which allows MPX-using KVM guests to continue to function"

* tag 'mpx-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-mpx:
  x86/mpx: remove MPX from arch/x86
  mm: remove arch_bprm_mm_init() hook
  x86/mpx: remove bounds exception code
  x86/mpx: remove build infrastructure
  x86/alternatives: add missing insn.h include
2020-01-30 16:11:50 -08:00
Linus Torvalds
ca9b5b6283 TTY/Serial driver updates for 5.6-rc1
Here are the big set of tty and serial driver updates for 5.6-rc1
 
 Included in here are:
 	- dummy_con cleanups (touches lots of arch code)
 	- sysrq logic cleanups (touches lots of serial drivers)
 	- samsung driver fixes (wasn't really being built)
 	- conmakeshash move to tty subdir out of scripts
 	- lots of small tty/serial driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXjFRBg8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yn2VACgkge7vTeUNeZFc+6F4NWphAQ5tCQAoK/MMbU6
 0O8ef7PjFwCU4s227UTv
 =6m40
 -----END PGP SIGNATURE-----

Merge tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here are the big set of tty and serial driver updates for 5.6-rc1

  Included in here are:
   - dummy_con cleanups (touches lots of arch code)
   - sysrq logic cleanups (touches lots of serial drivers)
   - samsung driver fixes (wasn't really being built)
   - conmakeshash move to tty subdir out of scripts
   - lots of small tty/serial driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: n_hdlc: Use flexible-array member and struct_size() helper
  tty: baudrate: SPARC supports few more baud rates
  tty: baudrate: Synchronise baud_table[] and baud_bits[]
  tty: serial: meson_uart: Add support for kernel debugger
  serial: imx: fix a race condition in receive path
  serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  serial: 8250_bcm2835aux: Use generic remapping code
  serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  serial_core: Remove unused member in uart_port
  vt: Correct comment documenting do_take_over_console()
  vt: Delete comment referencing non-existent unbind_con_driver()
  arch/xtensa/setup: Drop dummy_con initialization
  arch/x86/setup: Drop dummy_con initialization
  arch/unicore32/setup: Drop dummy_con initialization
  arch/sparc/setup: Drop dummy_con initialization
  arch/sh/setup: Drop dummy_con initialization
  arch/s390/setup: Drop dummy_con initialization
  ...
2020-01-29 10:13:27 -08:00
Thomas Gleixner
979923871f x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
Tony reported a boot regression caused by the recent workaround for systems
which have a disabled (clock gate off) PIT.

On his machine the kernel fails to initialize the PIT because
apic_needs_pit() does not take into account whether the local APIC
interrupt delivery mode will actually allow to setup and use the local
APIC timer. This should be easy to reproduce with acpi=off on the
command line which also disables HPET.

Due to the way the PIT/HPET and APIC setup ordering works (APIC setup can
require working PIT/HPET) the information is not available at the point
where apic_needs_pit() makes this decision.

To address this, split out the interrupt mode selection from
apic_intr_mode_init(), invoke the selection before making the decision
whether PIT is required or not, and add the missing checks into
apic_needs_pit().

Fixes: c8c4076723 ("x86/timer: Skip PIT initialization on modern chipsets")
Reported-by: Anthony Buckley <tony.buckley000@gmail.com>
Tested-by: Anthony Buckley <tony.buckley000@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Daniel Drake <drake@endlessm.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206125
Link: https://lore.kernel.org/r/87sgk6tmk2.fsf@nanos.tec.linutronix.de
2020-01-29 12:50:12 +01:00
Linus Torvalds
511fdb7844 Merge branch 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mtrr updates from Ingo Molnar:
 "Two changes: restrict /proc/mtrr to CAP_SYS_ADMIN, plus a cleanup"

* 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mtrr: Require CAP_SYS_ADMIN for all access
  x86/mtrr: Get rid of mtrr_seq_show() forward declaration
2020-01-28 13:06:05 -08:00
Linus Torvalds
4d6245ce8c Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 FPU updates from Ingo Molnar:
 "Three changes: fix a race that can result in FPU corruption, plus two
  cleanups"

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Deactivate FPU state after failure during state load
  x86/fpu/xstate: Make xfeature_is_supervisor()/xfeature_is_user() return bool
  x86/fpu/xstate: Fix small issues
2020-01-28 13:04:38 -08:00
Linus Torvalds
c0275ae758 Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu-features updates from Ingo Molnar:
 "The biggest change in this cycle was a large series from Sean
  Christopherson to clean up the handling of VMX features. This both
  fixes bugs/inconsistencies and makes the code more coherent and
  future-proof.

  There are also two cleanups and a minor TSX syslog messages
  enhancement"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/cpu: Remove redundant cpu_detect_cache_sizes() call
  x86/cpu: Print "VMX disabled" error message iff KVM is enabled
  KVM: VMX: Allow KVM_INTEL when building for Centaur and/or Zhaoxin CPUs
  perf/x86: Provide stubs of KVM helpers for non-Intel CPUs
  KVM: VMX: Use VMX_FEATURE_* flags to define VMCS control bits
  KVM: VMX: Check for full VMX support when verifying CPU compatibility
  KVM: VMX: Use VMX feature flag to query BIOS enabling
  KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR
  x86/cpufeatures: Add flag to track whether MSR IA32_FEAT_CTL is configured
  x86/cpu: Set synthetic VMX cpufeatures during init_ia32_feat_ctl()
  x86/cpu: Print VMX flags in /proc/cpuinfo using VMX_FEATURES_*
  x86/cpu: Detect VMX features on Intel, Centaur and Zhaoxin CPUs
  x86/vmx: Introduce VMX_FEATURES_*
  x86/cpu: Clear VMX feature flag if VMX is not fully enabled
  x86/zhaoxin: Use common IA32_FEAT_CTL MSR initialization
  x86/centaur: Use common IA32_FEAT_CTL MSR initialization
  x86/mce: WARN once if IA32_FEAT_CTL MSR is left unlocked
  x86/intel: Initialize IA32_FEAT_CTL MSR at boot
  tools/x86: Sync msr-index.h from kernel sources
  selftests, kvm: Replace manual MSR defs with common msr-index.h
  ...
2020-01-28 12:46:42 -08:00
Giovanni Gherdovich
918229cdd5 x86/intel_pstate: Handle runtime turbo disablement/enablement in frequency invariance
On some platforms such as the Dell XPS 13 laptop the firmware disables turbo
when the machine is disconnected from AC, and viceversa it enables it again
when it's reconnected. In these cases a _PPC ACPI notification is issued.

The scheduler needs to know freq_max for frequency-invariant calculations.
To account for turbo availability to come and go, record freq_max at boot as
if turbo was available and store it in a helper variable. Use a setter
function to swap between freq_base and freq_max every time turbo goes off or on.

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-7-ggherdovich@suse.cz
2020-01-28 21:37:06 +01:00
Giovanni Gherdovich
298c6f99bf x86, sched: Add support for frequency invariance on ATOM
The scheduler needs the ratio freq_curr/freq_max for frequency-invariant
accounting. On all ATOM CPUs prior to Goldmont, set freq_max to the 1-core
turbo ratio.

We intended to perform tests validating that this patch doesn't regress in
terms of energy efficiency, given that this is the primary concern on Atom
processors. Alas, we found out that turbostat doesn't support reading RAPL
interfaces on our test machine (Airmont), and we don't have external equipment
to measure power consumption; all we have is the performance results of the
benchmarks we ran.

Test machine:

Platform    : Dell Wyse 3040 Thin Client[1]
CPU Model   : Intel Atom x5-Z8350 (aka Cherry Trail, aka Airmont)
Fam/Mod/Ste : 6:76:4
Topology    : 1 socket, 4 cores / 4 threads
Memory      : 2G
Storage     : onboard flash, XFS filesystem

[1] https://www.dell.com/en-us/work/shop/wyse-endpoints-and-software/wyse-3040-thin-client/spd/wyse-3040-thin-client

Base frequency and available turbo levels (MHz):

    Min Operating Freq   266 |***
    Low Freq Mode        800 |********
    Base Freq           2400 |************************
    4 Cores             2800 |****************************
    3 Cores             2800 |****************************
    2 Cores             3200 |********************************
    1 Core              3200 |********************************

Tested kernels:

Baseline      : v5.4-rc1,              intel_pstate passive,  schedutil
Comparison #1 : v5.4-rc1,              intel_pstate active ,  powersave
Comparison #2 : v5.4-rc1, this patch,  intel_pstate passive,  schedutil

tbench, hackbench and kernbench performed the same under all three kernels;
dbench ran faster with intel_pstate/powersave and the git unit tests were a
lot faster with intel_pstate/powersave and invariant schedutil wrt the
baseline. Not that any of this is terrbily interesting anyway, one doesn't buy
an Atom system to go fast. Power consumption regressions aren't expected but
we lack the equipment to make that measurement. Turbostat seems to think that
reading RAPL on this machine isn't a good idea and we're trusting that
decision.

comparison ratio of performance with baseline; 1.00 means neutral,
lower is better:

                      I_PSTATE      FREQ-INV
    ----------------------------------------
    dbench                0.90             ~
    kernbench             0.98          0.97
    gitsource             0.63          0.43

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-6-ggherdovich@suse.cz
2020-01-28 21:37:05 +01:00
Giovanni Gherdovich
eacf0474ae x86, sched: Add support for frequency invariance on ATOM_GOLDMONT*
The scheduler needs the ratio freq_curr/freq_max for frequency-invariant
accounting. On GOLDMONT (aka Apollo Lake), GOLDMONT_D (aka Denverton) and
GOLDMONT_PLUS CPUs (aka Gemini Lake) set freq_max to the highest frequency
reported by the CPU.

The encoding of turbo ratios for GOLDMONT* is identical to the one for
SKYLAKE_X, but we treat the Atom case apart because we want to set freq_max to
a higher value, thus the ratio freq_curr/freq_max to be lower, leading to more
conservative frequency selections (favoring power efficiency).

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-5-ggherdovich@suse.cz
2020-01-28 21:37:04 +01:00
Giovanni Gherdovich
8bea0dfb4a x86, sched: Add support for frequency invariance on XEON_PHI_KNL/KNM
The scheduler needs the ratio freq_curr/freq_max for frequency-invariant
accounting. On Xeon Phi CPUs set freq_max to the second-highest frequency
reported by the CPU.

Xeon Phi CPUs such as Knights Landing and Knights Mill typically have either
one or two turbo frequencies; in the former case that's 100 MHz above the base
frequency, in the latter case the two levels are 100 MHz and 200 MHz above
base frequency.

We set freq_max to the second-highest frequency reported by the CPU. This
could be the base frequency (if only one turbo level is available) or the first
turbo level (if two levels are available). The rationale is to compromise
between power efficiency or performance -- going straight to max turbo would
favor efficiency and blindly using base freq would favor performance.

For reference, this is how MSR_TURBO_RATIO_LIMIT must be parsed on a Xeon Phi
to get the available frequencies (taken from a comment in turbostat's sources):

    [0] -- Reserved
    [7:1] -- Base value of number of active cores of bucket 1.
    [15:8] -- Base value of freq ratio of bucket 1.
    [20:16] -- +ve delta of number of active cores of bucket 2.
    i.e. active cores of bucket 2 =
    active cores of bucket 1 + delta
    [23:21] -- Negative delta of freq ratio of bucket 2.
    i.e. freq ratio of bucket 2 =
    freq ratio of bucket 1 - delta
    [28:24]-- +ve delta of number of active cores of bucket 3.
    [31:29]-- -ve delta of freq ratio of bucket 3.
    [36:32]-- +ve delta of number of active cores of bucket 4.
    [39:37]-- -ve delta of freq ratio of bucket 4.
    [44:40]-- +ve delta of number of active cores of bucket 5.
    [47:45]-- -ve delta of freq ratio of bucket 5.
    [52:48]-- +ve delta of number of active cores of bucket 6.
    [55:53]-- -ve delta of freq ratio of bucket 6.
    [60:56]-- +ve delta of number of active cores of bucket 7.
    [63:61]-- -ve delta of freq ratio of bucket 7.

1. PERFORMANCE EVALUATION: TBENCH +5%
2. NEUTRAL BENCHMARKS (ALL OTHERS)
3. TEST SETUP

1. PERFORMANCE EVALUATION: TBENCH +5%
-------------------------------------

A performance evaluation was conducted on a Knights Mill machine (see "Test
Setup" below), were the frequency-invariance patch (on schedutil) is compared
to both non-invariant schedutil and active intel_pstate with powersave: all
three tested kernels behave the same performance-wise and with regard to power
consumption (performance per watt). The only notable difference is tbench:

comparison ratio of performance with baseline; 1.00 means neutral,
higher is better:

                      I_PSTATE      FREQ-INV
    ----------------------------------------
    tbench                1.04          1.05

performance-per-watt ratios with baseline; 1.00 means neutral, higher is better:

                      I_PSTATE      FREQ-INV
    ----------------------------------------
    tbench                1.03          1.04

which essentially means that frequency-invariant schedutil is 5% better than
baseline, the same as intel_pstate+powersave.

As the results above are averaged over the varying parameter, here the detailed
table.

Varying parameter  : number of clients
Unit               : MB/sec (higher is better)

                    5.2.0 vanilla (BASELINE)                 5.2.0 intel_pstate                     5.2.0 freq-inv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean   1         49.06  +- 2.12% (        )         51.66  +- 1.52% (   5.30%)         52.87  +- 0.88% (   7.76%)
Hmean   2         93.82  +- 0.45% (        )        103.24  +- 0.70% (  10.05%)        105.90  +- 0.70% (  12.88%)
Hmean   4        192.46  +- 1.15% (        )        215.95  +- 0.60% (  12.21%)        215.78  +- 1.43% (  12.12%)
Hmean   8        406.74  +- 2.58% (        )        438.58  +- 0.36% (   7.83%)        437.61  +- 0.97% (   7.59%)
Hmean   16       857.70  +- 1.22% (        )        890.26  +- 0.72% (   3.80%)        889.11  +- 0.73% (   3.66%)
Hmean   32      1760.10  +- 0.92% (        )       1791.70  +- 0.44% (   1.79%)       1787.95  +- 0.44% (   1.58%)
Hmean   64      3183.50  +- 0.34% (        )       3183.19  +- 0.36% (  -0.01%)       3187.53  +- 0.36% (   0.13%)
Hmean   128     4830.96  +- 0.31% (        )       4846.53  +- 0.30% (   0.32%)       4855.86  +- 0.30% (   0.52%)
Hmean   256     5467.98  +- 0.38% (        )       5793.80  +- 0.28% (   5.96%)       5821.94  +- 0.17% (   6.47%)
Hmean   512     5398.10  +- 0.06% (        )       5745.56  +- 0.08% (   6.44%)       5503.68  +- 0.07% (   1.96%)
Hmean   1024    5290.43  +- 0.63% (        )       5221.07  +- 0.47% (  -1.31%)       5277.22  +- 0.80% (  -0.25%)
Hmean   1088    5139.71  +- 0.57% (        )       5236.02  +- 0.71% (   1.87%)       5190.57  +- 0.41% (   0.99%)

2. NEUTRAL BENCHMARKS (ALL OTHERS)
----------------------------------

* pgbench (both read/write and read-only)
* NASA Parallel Benchmarks (NPB), MPI or OpenMP for message-passing
* hackbench
* netperf
* dbench
* kernbench
* gitsource (git unit test suite)

3. TEST SETUP
-------------

Test machine:

CPU Model   : Intel Xeon Phi CPU 7255 @ 1.10GHz (a.k.a. Knights Mill)
Fam/Mod/Ste : 6:133:0
Topology    : 1 socket, 68 cores / 272 threads
Memory      : 96G
Storage     : rotary, XFS filesystem

Max EFFICiency, BASE frequency and available turbo levels (MHz):

    EFFIC   1000 |**********
    BASE    1100 |***********
    68C     1100 |***********
    30C     1200 |************

Tested kernels:

Baseline      : v5.2,              intel_pstate passive,  schedutil
Comparison #1 : v5.2,              intel_pstate active ,  powersave
Comparison #2 : v5.2, this patch,  intel_pstate passive,  schedutil

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-4-ggherdovich@suse.cz
2020-01-28 21:37:02 +01:00
Giovanni Gherdovich
2a0abc5969 x86, sched: Add support for frequency invariance on SKYLAKE_X
The scheduler needs the ratio freq_curr/freq_max for frequency-invariant
accounting. On SKYLAKE_X CPUs set freq_max to the highest frequency that can
be sustained by a group of at least 4 cores.

From the changelog of commit 31e07522be ("tools/power turbostat: fix
decoding for GLM, DNV, SKX turbo-ratio limits"):

 >   Newer processors do not hard-code the the number of cpus in each bin
 >   to {1, 2, 3, 4, 5, 6, 7, 8}  Rather, they can specify any number
 >   of CPUS in each of the 8 bins:
 >
 >   eg.
 >
 >   ...
 >   37 * 100.0 = 3600.0 MHz max turbo 4 active cores
 >   38 * 100.0 = 3700.0 MHz max turbo 3 active cores
 >   39 * 100.0 = 3800.0 MHz max turbo 2 active cores
 >   39 * 100.0 = 3900.0 MHz max turbo 1 active cores
 >
 >   could now look something like this:
 >
 >   ...
 >   37 * 100.0 = 3600.0 MHz max turbo 16 active cores
 >   38 * 100.0 = 3700.0 MHz max turbo 8 active cores
 >   39 * 100.0 = 3800.0 MHz max turbo 4 active cores
 >   39 * 100.0 = 3900.0 MHz max turbo 2 active cores

This encoding of turbo levels applies to both SKYLAKE_X and GOLDMONT/GOLDMONT_D,
but we treat these two classes in separate commits because their freq_max
values need to be different. For SKX we prefer a lower freq_max in the ratio
freq_curr/freq_max, allowing load and utilization to overshoot and the
schedutil governor to be more performance-oriented. Models from the Atom
series (such as GOLDMONT*) are handled in a forthcoming commit as they have to
favor power-efficiency over performance.

Results from a performance evaluation follow.

1. TEST SETUP
2. NEUTRAL BENCHMARKS
3. NON-NEUTRAL BENCHMARKS
4. DETAILED TABLES

1. TEST SETUP
-------------

Test machine:

CPU Model   : Intel Xeon Platinum 8260L CPU @ 2.40GHz (a.k.a. Cascade Lake)
Fam/Mod/Ste : 6:85:6
Topology    : 2 sockets, 24 cores / 48 threads each socket
Memory      : 192G
Storage     : SSD, XFS filesystem

Max EFFICiency, BASE frequency and available turbo levels (MHz):

    EFFIC   1000 |**********
    BASE    2400 |************************
    24C     3100 |*******************************
    20C     3300 |*********************************
    16C     3600 |************************************
    12C     3600 |************************************
    8C      3600 |************************************
    4C      3700 |*************************************
    2C      3900 |***************************************

Tested kernels:

Baseline      : v5.2,              intel_pstate passive,  schedutil
Comparison #1 : v5.2,              intel_pstate active ,  powersave+HWP
Comparison #2 : v5.2, this patch,  intel_pstate passive,  schedutil

2. NEUTRAL BENCHMARKS
---------------------

* pgbench read/write
* NASA Parallel Benchmarks (NPB), MPI or OpenMP for message-passing
* hackbench
* netperf

3. NON-NEUTRAL BENCHMARKS
-------------------------

comparison ratio with baseline; 1.00 means neutral, higher is better:

                      I_PSTATE      FREQ-INV
    ----------------------------------------
    pgbench read-only     1.10             ~
    tbench                1.82          1.14

comparison ratio with baseline; 1.00 means neutral, lower is better:

                      I_PSTATE      FREQ-INV
    ----------------------------------------
    dbench                   ~          0.97
    kernbench             0.88          0.78
    gitsource[*]             ~          0.46

[*] "gitsource" consists in running git's unit tests
tilde (~) means 1.00, ie result identical to baseline

Performance per watt:

performance-per-watt ratios with baseline; 1.00 means neutral, higher is better:

		      I_PSTATE      FREQ-INV
    ----------------------------------------
    dbench                0.92          0.91
    tbench                1.26          1.04
    kernbench             0.95          0.96
    gitsource             1.03          1.30

Similarly to earlier Xeons, measurable performance gains over non-invariant
schedutil are observed on dbench, tbench, kernel compilation and running the
git unit tests suite. Looking at the detailed tables show that the patch
scores the largest difference when the machine is lightly loaded. Power
efficiency suffers lightly on kernbench and a bit more on dbench, but largely
improves on gitsource (which also runs considerably faster). For reference, we
also report results using active intel_pstate with powersave and HWP; the
largest gap between non-invariant schedutil and intel_pstate+powersave is
still tbench, which runs 82% better and with 26% improved efficiency on the
latter configuration -- this divide isn't closed yet by frequency-invariant
schedutil.

4. DETAILED TABLES
------------------

Benchmark          : tbench4 (i.e. dbench4 over the network, actually loopback)
Varying parameter  : number of clients
Unit               : MB/sec (higher is better)

                     5.2.0 vanilla (BASELINE)            5.2.0 intel_pstate/HWP                    5.2.0 freq-inv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean   1         183.56  +- 0.21% (        )       516.12  +- 0.57% ( 181.18%)       185.59  +- 0.59% (   1.11%)
Hmean   2         365.75  +- 0.25% (        )      1015.14  +- 0.33% ( 177.55%)       402.59  +- 4.48% (  10.07%)
Hmean   4         720.99  +- 0.44% (        )      1951.75  +- 0.28% ( 170.70%)       738.39  +- 1.72% (   2.41%)
Hmean   8        1449.93  +- 0.34% (        )      3830.56  +- 0.24% ( 164.19%)      1750.36  +- 4.65% (  20.72%)
Hmean   16       2874.26  +- 0.57% (        )      7381.62  +- 0.53% ( 156.82%)      4348.35  +- 2.22% (  51.29%)
Hmean   32       6116.17  +- 5.10% (        )     13013.05  +- 0.08% ( 112.76%)      8980.35  +- 0.66% (  46.83%)
Hmean   64      14485.04  +- 3.46% (        )     17835.12  +- 0.35% (  23.13%)     16540.73  +- 0.51% (  14.19%)
Hmean   128     30779.16  +- 3.20% (        )     32796.94  +- 2.13% (   6.56%)     31512.58  +- 0.20% (   2.38%)
Hmean   256     34664.66  +- 0.81% (        )     34604.67  +- 0.46% (  -0.17%)     34943.70  +- 0.25% (   0.80%)
Hmean   384     33957.51  +- 0.11% (        )     34091.50  +- 0.14% (   0.39%)     33921.41  +- 0.09% (  -0.11%)

Benchmark          : kernbench (kernel compilation)
Varying parameter  : number of jobs
Unit               : seconds (lower is better)

                    5.2.0 vanilla (BASELINE)             5.2.0 intel_pstate/HWP                     5.2.0 freq-inv
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean   2        332.94  +- 0.40% (        )        260.16  +- 0.45% (  21.86%)        233.56  +- 0.21% (  29.85%)
Amean   4        173.04  +- 0.43% (        )        138.76  +- 0.03% (  19.81%)        123.59  +- 0.11% (  28.58%)
Amean   8         89.65  +- 0.20% (        )         73.54  +- 0.09% (  17.97%)         65.69  +- 0.10% (  26.72%)
Amean   16        48.08  +- 1.41% (        )         41.64  +- 1.61% (  13.40%)         36.00  +- 1.80% (  25.11%)
Amean   32        28.78  +- 0.72% (        )         26.61  +- 1.99% (   7.55%)         23.19  +- 1.68% (  19.43%)
Amean   64        20.46  +- 1.85% (        )         19.76  +- 0.35% (   3.42%)         17.38  +- 0.92% (  15.06%)
Amean   128       18.69  +- 1.70% (        )         17.59  +- 1.04% (   5.90%)         15.73  +- 1.40% (  15.85%)
Amean   192       18.82  +- 1.01% (        )         17.76  +- 0.77% (   5.67%)         15.57  +- 1.80% (  17.28%)

Benchmark          : gitsource (time to run the git unit test suite)
Varying parameter  : none
Unit               : seconds (lower is better)

                 5.2.0 vanilla (BASELINE)           5.2.0 intel_pstate/HWP                    5.2.0 freq-inv
- - - - - - - -  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean         792.49  +- 0.20% (        )      779.35  +- 0.24% (   1.66%)      427.14  +- 0.16% (   46.10%)

Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-3-ggherdovich@suse.cz
2020-01-28 21:37:01 +01:00
Giovanni Gherdovich
1567c3e346 x86, sched: Add support for frequency invariance
Implement arch_scale_freq_capacity() for 'modern' x86. This function
is used by the scheduler to correctly account usage in the face of
DVFS.

The present patch addresses Intel processors specifically and has positive
performance and performance-per-watt implications for the schedutil cpufreq
governor, bringing it closer to, if not on-par with, the powersave governor
from the intel_pstate driver/framework.

Large performance gains are obtained when the machine is lightly loaded and
no regression are observed at saturation. The benchmarks with the largest
gains are kernel compilation, tbench (the networking version of dbench) and
shell-intensive workloads.

1. FREQUENCY INVARIANCE: MOTIVATION
   * Without it, a task looks larger if the CPU runs slower

2. PECULIARITIES OF X86
   * freq invariance accounting requires knowing the ratio freq_curr/freq_max
   2.1 CURRENT FREQUENCY
       * Use delta_APERF / delta_MPERF * freq_base (a.k.a "BusyMHz")
   2.2 MAX FREQUENCY
       * It varies with time (turbo). As an approximation, we set it to a
         constant, i.e. 4-cores turbo frequency.

3. EFFECTS ON THE SCHEDUTIL FREQUENCY GOVERNOR
   * The invariant schedutil's formula has no feedback loop and reacts faster
     to utilization changes

4. KNOWN LIMITATIONS
   * In some cases tasks can't reach max util despite how hard they try

5. PERFORMANCE TESTING
   5.1 MACHINES
       * Skylake, Broadwell, Haswell
   5.2 SETUP
       * baseline Linux v5.2 w/ non-invariant schedutil. Tested freq_max = 1-2-3-4-8-12
         active cores turbo w/ invariant schedutil, and intel_pstate/powersave
   5.3 BENCHMARK RESULTS
       5.3.1 NEUTRAL BENCHMARKS
             * NAS Parallel Benchmark (HPC), hackbench
       5.3.2 NON-NEUTRAL BENCHMARKS
             * tbench (10-30% better), kernbench (10-15% better),
               shell-intensive-scripts (30-50% better)
             * no regressions
       5.3.3 SELECTION OF DETAILED RESULTS
       5.3.4 POWER CONSUMPTION, PERFORMANCE-PER-WATT
             * dbench (5% worse on one machine), kernbench (3% worse),
               tbench (5-10% better), shell-intensive-scripts (10-40% better)

6. MICROARCH'ES ADDRESSED HERE
   * Xeon Core before Scalable Performance processors line (Xeon Gold/Platinum
     etc have different MSRs semantic for querying turbo levels)

7. REFERENCES
   * MMTests performance testing framework, github.com/gormanm/mmtests

 +-------------------------------------------------------------------------+
 | 1. FREQUENCY INVARIANCE: MOTIVATION
 +-------------------------------------------------------------------------+

For example; suppose a CPU has two frequencies: 500 and 1000 Mhz. When
running a task that would consume 1/3rd of a CPU at 1000 MHz, it would
appear to consume 2/3rd (or 66.6%) when running at 500 MHz, giving the
false impression this CPU is almost at capacity, even though it can go
faster [*]. In a nutshell, without frequency scale-invariance tasks look
larger just because the CPU is running slower.

[*] (footnote: this assumes a linear frequency/performance relation; which
everybody knows to be false, but given realities its the best approximation
we can make.)

 +-------------------------------------------------------------------------+
 | 2. PECULIARITIES OF X86
 +-------------------------------------------------------------------------+

Accounting for frequency changes in PELT signals requires the computation of
the ratio freq_curr / freq_max. On x86 neither of those terms is readily
available.

2.1 CURRENT FREQUENCY
====================

Since modern x86 has hardware control over the actual frequency we run
at (because amongst other things, Turbo-Mode), we cannot simply use
the frequency as requested through cpufreq.

Instead we use the APERF/MPERF MSRs to compute the effective frequency
over the recent past. Also, because reading MSRs is expensive, don't
do so every time we need the value, but amortize the cost by doing it
every tick.

2.2 MAX FREQUENCY
=================

Obtaining freq_max is also non-trivial because at any time the hardware can
provide a frequency boost to a selected subset of cores if the package has
enough power to spare (eg: Turbo Boost). This means that the maximum frequency
available to a given core changes with time.

The approach taken in this change is to arbitrarily set freq_max to a constant
value at boot. The value chosen is the "4-cores (4C) turbo frequency" on most
microarchitectures, after evaluating the following candidates:

    * 1-core (1C) turbo frequency (the fastest turbo state available)
    * around base frequency (a.k.a. max P-state)
    * something in between, such as 4C turbo

To interpret these options, consider that this is the denominator in
freq_curr/freq_max, and that ratio will be used to scale PELT signals such as
util_avg and load_avg. A large denominator will undershoot (util_avg looks a
bit smaller than it really is), viceversa with a smaller denominator PELT
signals will tend to overshoot. Given that PELT drives frequency selection
in the schedutil governor, we will have:

    freq_max set to     | effect on DVFS
    --------------------+------------------
    1C turbo            | power efficiency (lower freq choices)
    base freq           | performance (higher util_avg, higher freq requests)
    4C turbo            | a bit of both

4C turbo proves to be a good compromise in a number of benchmarks (see below).

 +-------------------------------------------------------------------------+
 | 3. EFFECTS ON THE SCHEDUTIL FREQUENCY GOVERNOR
 +-------------------------------------------------------------------------+

Once an architecture implements a frequency scale-invariant utilization (the
PELT signal util_avg), schedutil switches its frequency selection formula from

    freq_next = 1.25 * freq_curr * util            [non-invariant util signal]

to

    freq_next = 1.25 * freq_max * util             [invariant util signal]

where, in the second formula, freq_max is set to the 1C turbo frequency (max
turbo). The advantage of the second formula, whose usage we unlock with this
patch, is that freq_next doesn't depend on the current frequency in an
iterative fashion, but can jump to any frequency in a single update. This
absence of feedback in the formula makes it quicker to react to utilization
changes and more robust against pathological instabilities.

Compare it to the update formula of intel_pstate/powersave:

    freq_next = 1.25 * freq_max * Busy%

where again freq_max is 1C turbo and Busy% is the percentage of time not spent
idling (calculated with delta_MPERF / delta_TSC); essentially the same as
invariant schedutil, and largely responsible for intel_pstate/powersave good
reputation. The non-invariant schedutil formula is derived from the invariant
one by approximating util_inv with util_raw * freq_curr / freq_max, but this
has limitations.

Testing shows improved performances due to better frequency selections when
the machine is lightly loaded, and essentially no change in behaviour at
saturation / overutilization.

 +-------------------------------------------------------------------------+
 | 4. KNOWN LIMITATIONS
 +-------------------------------------------------------------------------+

It's been shown that it is possible to create pathological scenarios where a
CPU-bound task cannot reach max utilization, if the normalizing factor
freq_max is fixed to a constant value (see [Lelli-2018]).

If freq_max is set to 4C turbo as we do here, one needs to peg at least 5
cores in a package doing some busywork, and observe that none of those task
will ever reach max util (1024) because they're all running at less than the
4C turbo frequency.

While this concern still applies, we believe the performance benefit of
frequency scale-invariant PELT signals outweights the cost of this limitation.

 [Lelli-2018]
 https://lore.kernel.org/lkml/20180517150418.GF22493@localhost.localdomain/

 +-------------------------------------------------------------------------+
 | 5. PERFORMANCE TESTING
 +-------------------------------------------------------------------------+

5.1 MACHINES
============

We tested the patch on three machines, with Skylake, Broadwell and Haswell
CPUs. The details are below, together with the available turbo ratios as
reported by the appropriate MSRs.

* 8x-SKYLAKE-UMA:
  Single socket E3-1240 v5, Skylake 4 cores/8 threads
  Max EFFiciency, BASE frequency and available turbo levels (MHz):

    EFFIC    800 |********
    BASE    3500 |***********************************
    4C      3700 |*************************************
    3C      3800 |**************************************
    2C      3900 |***************************************
    1C      3900 |***************************************

* 80x-BROADWELL-NUMA:
  Two sockets E5-2698 v4, 2x Broadwell 20 cores/40 threads
  Max EFFiciency, BASE frequency and available turbo levels (MHz):

    EFFIC   1200 |************
    BASE    2200 |**********************
    8C      2900 |*****************************
    7C      3000 |******************************
    6C      3100 |*******************************
    5C      3200 |********************************
    4C      3300 |*********************************
    3C      3400 |**********************************
    2C      3600 |************************************
    1C      3600 |************************************

* 48x-HASWELL-NUMA
  Two sockets E5-2670 v3, 2x Haswell 12 cores/24 threads
  Max EFFiciency, BASE frequency and available turbo levels (MHz):

    EFFIC   1200 |************
    BASE    2300 |***********************
    12C     2600 |**************************
    11C     2600 |**************************
    10C     2600 |**************************
    9C      2600 |**************************
    8C      2600 |**************************
    7C      2600 |**************************
    6C      2600 |**************************
    5C      2700 |***************************
    4C      2800 |****************************
    3C      2900 |*****************************
    2C      3100 |*******************************
    1C      3100 |*******************************

5.2 SETUP
=========

* The baseline is Linux v5.2 with schedutil (non-invariant) and the intel_pstate
  driver in passive mode.
* The rationale for choosing the various freq_max values to test have been to
  try all the 1-2-3-4C turbo levels (note that 1C and 2C turbo are identical
  on all machines), plus one more value closer to base_freq but still in the
  turbo range (8C turbo for both 80x-BROADWELL-NUMA and 48x-HASWELL-NUMA).
* In addition we've run all tests with intel_pstate/powersave for comparison.
* The filesystem is always XFS, the userspace is openSUSE Leap 15.1.
* 8x-SKYLAKE-UMA is capable of HWP (Hardware-Managed P-States), so the runs
  with active intel_pstate on this machine use that.

This gives, in terms of combinations tested on each machine:

* 8x-SKYLAKE-UMA
  * Baseline: Linux v5.2, non-invariant schedutil, intel_pstate passive
  * intel_pstate active + powersave + HWP
  * invariant schedutil, freq_max = 1C turbo
  * invariant schedutil, freq_max = 3C turbo
  * invariant schedutil, freq_max = 4C turbo

* both 80x-BROADWELL-NUMA and 48x-HASWELL-NUMA
  * [same as 8x-SKYLAKE-UMA, but no HWP capable]
  * invariant schedutil, freq_max = 8C turbo
    (which on 48x-HASWELL-NUMA is the same as 12C turbo, or "all cores turbo")

5.3 BENCHMARK RESULTS
=====================

5.3.1 NEUTRAL BENCHMARKS
------------------------

Tests that didn't show any measurable difference in performance on any of the
test machines between non-invariant schedutil and our patch are:

* NAS Parallel Benchmarks (NPB) using either MPI or openMP for IPC, any
  computational kernel
* flexible I/O (FIO)
* hackbench (using threads or processes, and using pipes or sockets)

5.3.2 NON-NEUTRAL BENCHMARKS
----------------------------

What follow are summary tables where each benchmark result is given a score.

* A tilde (~) means a neutral result, i.e. no difference from baseline.
* Scores are computed with the ratio result_new / result_baseline, so a tilde
  means a score of 1.00.
* The results in the score ratio are the geometric means of results running
  the benchmark with different parameters (eg: for kernbench: using 1, 2, 4,
  ... number of processes; for pgbench: varying the number of clients, and so
  on).
* The first three tables show higher-is-better kind of tests (i.e. measured in
  operations/second), the subsequent three show lower-is-better kind of tests
  (i.e. the workload is fixed and we measure elapsed time, think kernbench).
* "gitsource" is a name we made up for the test consisting in running the
  entire unit tests suite of the Git SCM and measuring how long it takes. We
  take it as a typical example of shell-intensive serialized workload.
* In the "I_PSTATE" column we have the results for intel_pstate/powersave. Other
  columns show invariant schedutil for different values of freq_max. 4C turbo
  is circled as it's the value we've chosen for the final implementation.

80x-BROADWELL-NUMA (comparison ratio; higher is better)
                                         +------+
                 I_PSTATE   1C     3C    | 4C   |  8C
pgbench-ro           1.14   ~      ~     | 1.11 |  1.14
pgbench-rw           ~      ~      ~     | ~    |  ~
netperf-udp          1.06   ~      1.06  | 1.05 |  1.07
netperf-tcp          ~      1.03   ~     | 1.01 |  1.02
tbench4              1.57   1.18   1.22  | 1.30 |  1.56
                                         +------+

8x-SKYLAKE-UMA (comparison ratio; higher is better)
                                         +------+
             I_PSTATE/HWP   1C     3C    | 4C   |
pgbench-ro           ~      ~      ~     | ~    |
pgbench-rw           ~      ~      ~     | ~    |
netperf-udp          ~      ~      ~     | ~    |
netperf-tcp          ~      ~      ~     | ~    |
tbench4              1.30   1.14   1.14  | 1.16 |
                                         +------+

48x-HASWELL-NUMA (comparison ratio; higher is better)
                                         +------+
                 I_PSTATE   1C     3C    | 4C   |  12C
pgbench-ro           1.15   ~      ~     | 1.06 |  1.16
pgbench-rw           ~      ~      ~     | ~    |  ~
netperf-udp          1.05   0.97   1.04  | 1.04 |  1.02
netperf-tcp          0.96   1.01   1.01  | 1.01 |  1.01
tbench4              1.50   1.05   1.13  | 1.13 |  1.25
                                         +------+

In the table above we see that active intel_pstate is slightly better than our
4C-turbo patch (both in reference to the baseline non-invariant schedutil) on
read-only pgbench and much better on tbench. Both cases are notable in which
it shows that lowering our freq_max (to 8C-turbo and 12C-turbo on
80x-BROADWELL-NUMA and 48x-HASWELL-NUMA respectively) helps invariant
schedutil to get closer.

If we ignore active intel_pstate and focus on the comparison with baseline
alone, there are several instances of double-digit performance improvement.

80x-BROADWELL-NUMA (comparison ratio; lower is better)
                                         +------+
                 I_PSTATE   1C     3C    | 4C   |  8C
dbench4              1.23   0.95   0.95  | 0.95 |  0.95
kernbench            0.93   0.83   0.83  | 0.83 |  0.82
gitsource            0.98   0.49   0.49  | 0.49 |  0.48
                                         +------+

8x-SKYLAKE-UMA (comparison ratio; lower is better)
                                         +------+
             I_PSTATE/HWP   1C     3C    | 4C   |
dbench4              ~      ~      ~     | ~    |
kernbench            ~      ~      ~     | ~    |
gitsource            0.92   0.55   0.55  | 0.55 |
                                         +------+

48x-HASWELL-NUMA (comparison ratio; lower is better)
                                         +------+
                 I_PSTATE   1C     3C    | 4C   |  8C
dbench4              ~      ~      ~     | ~    |  ~
kernbench            0.94   0.90   0.89  | 0.90 |  0.90
gitsource            0.97   0.69   0.69  | 0.69 |  0.69
                                         +------+

dbench is not very remarkable here, unless we notice how poorly active
intel_pstate is performing on 80x-BROADWELL-NUMA: 23% regression versus
non-invariant schedutil. We repeated that run getting consistent results. Out
of scope for the patch at hand, but deserving future investigation. Other than
that, we previously ran this campaign with Linux v5.0 and saw the patch doing
better on dbench a the time. We haven't checked closely and can only speculate
at this point.

On the NUMA boxes kernbench gets 10-15% improvements on average; we'll see in
the detailed tables that the gains concentrate on low process counts (lightly
loaded machines).

The test we call "gitsource" (running the git unit test suite, a long-running
single-threaded shell script) appears rather spectacular in this table (gains
of 30-50% depending on the machine). It is to be noted, however, that
gitsource has no adjustable parameters (such as the number of jobs in
kernbench, which we average over in order to get a single-number summary
score) and is exactly the kind of low-parallelism workload that benefits the
most from this patch. When looking at the detailed tables of kernbench or
tbench4, at low process or client counts one can see similar numbers.

5.3.3 SELECTION OF DETAILED RESULTS
-----------------------------------

Machine            : 48x-HASWELL-NUMA
Benchmark          : tbench4 (i.e. dbench4 over the network, actually loopback)
Varying parameter  : number of clients
Unit               : MB/sec (higher is better)

                   5.2.0 vanilla (BASELINE)               5.2.0 intel_pstate                   5.2.0 1C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean  1        126.73  +- 0.31% (        )      315.91  +- 0.66% ( 149.28%)      125.03  +- 0.76% (  -1.34%)
Hmean  2        258.04  +- 0.62% (        )      614.16  +- 0.51% ( 138.01%)      269.58  +- 1.45% (   4.47%)
Hmean  4        514.30  +- 0.67% (        )     1146.58  +- 0.54% ( 122.94%)      533.84  +- 1.99% (   3.80%)
Hmean  8       1111.38  +- 2.52% (        )     2159.78  +- 0.38% (  94.33%)     1359.92  +- 1.56% (  22.36%)
Hmean  16      2286.47  +- 1.36% (        )     3338.29  +- 0.21% (  46.00%)     2720.20  +- 0.52% (  18.97%)
Hmean  32      4704.84  +- 0.35% (        )     4759.03  +- 0.43% (   1.15%)     4774.48  +- 0.30% (   1.48%)
Hmean  64      7578.04  +- 0.27% (        )     7533.70  +- 0.43% (  -0.59%)     7462.17  +- 0.65% (  -1.53%)
Hmean  128     6998.52  +- 0.16% (        )     6987.59  +- 0.12% (  -0.16%)     6909.17  +- 0.14% (  -1.28%)
Hmean  192     6901.35  +- 0.25% (        )     6913.16  +- 0.10% (   0.17%)     6855.47  +- 0.21% (  -0.66%)

                             5.2.0 3C-turbo                   5.2.0 4C-turbo                  5.2.0 12C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean  1        128.43  +- 0.28% (   1.34%)      130.64  +- 3.81% (   3.09%)      153.71  +- 5.89% (  21.30%)
Hmean  2        311.70  +- 6.15% (  20.79%)      281.66  +- 3.40% (   9.15%)      305.08  +- 5.70% (  18.23%)
Hmean  4        641.98  +- 2.32% (  24.83%)      623.88  +- 5.28% (  21.31%)      906.84  +- 4.65% (  76.32%)
Hmean  8       1633.31  +- 1.56% (  46.96%)     1714.16  +- 0.93% (  54.24%)     2095.74  +- 0.47% (  88.57%)
Hmean  16      3047.24  +- 0.42% (  33.27%)     3155.02  +- 0.30% (  37.99%)     3634.58  +- 0.15% (  58.96%)
Hmean  32      4734.31  +- 0.60% (   0.63%)     4804.38  +- 0.23% (   2.12%)     4674.62  +- 0.27% (  -0.64%)
Hmean  64      7699.74  +- 0.35% (   1.61%)     7499.72  +- 0.34% (  -1.03%)     7659.03  +- 0.25% (   1.07%)
Hmean  128     6935.18  +- 0.15% (  -0.91%)     6942.54  +- 0.10% (  -0.80%)     7004.85  +- 0.12% (   0.09%)
Hmean  192     6901.62  +- 0.12% (   0.00%)     6856.93  +- 0.10% (  -0.64%)     6978.74  +- 0.10% (   1.12%)

This is one of the cases where the patch still can't surpass active
intel_pstate, not even when freq_max is as low as 12C-turbo. Otherwise, gains are
visible up to 16 clients and the saturated scenario is the same as baseline.

The scores in the summary table from the previous sections are ratios of
geometric means of the results over different clients, as seen in this table.

Machine            : 80x-BROADWELL-NUMA
Benchmark          : kernbench (kernel compilation)
Varying parameter  : number of jobs
Unit               : seconds (lower is better)

                   5.2.0 vanilla (BASELINE)               5.2.0 intel_pstate                   5.2.0 1C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean  2        379.68  +- 0.06% (        )      330.20  +- 0.43% (  13.03%)      285.93  +- 0.07% (  24.69%)
Amean  4        200.15  +- 0.24% (        )      175.89  +- 0.22% (  12.12%)      153.78  +- 0.25% (  23.17%)
Amean  8        106.20  +- 0.31% (        )       95.54  +- 0.23% (  10.03%)       86.74  +- 0.10% (  18.32%)
Amean  16        56.96  +- 1.31% (        )       53.25  +- 1.22% (   6.50%)       48.34  +- 1.73% (  15.13%)
Amean  32        34.80  +- 2.46% (        )       33.81  +- 0.77% (   2.83%)       30.28  +- 1.59% (  12.99%)
Amean  64        26.11  +- 1.63% (        )       25.04  +- 1.07% (   4.10%)       22.41  +- 2.37% (  14.16%)
Amean  128       24.80  +- 1.36% (        )       23.57  +- 1.23% (   4.93%)       21.44  +- 1.37% (  13.55%)
Amean  160       24.85  +- 0.56% (        )       23.85  +- 1.17% (   4.06%)       21.25  +- 1.12% (  14.49%)

                             5.2.0 3C-turbo                   5.2.0 4C-turbo                   5.2.0 8C-turbo
- - - - - - - -  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean  2        284.08  +- 0.13% (  25.18%)      283.96  +- 0.51% (  25.21%)      285.05  +- 0.21% (  24.92%)
Amean  4        153.18  +- 0.22% (  23.47%)      154.70  +- 1.64% (  22.71%)      153.64  +- 0.30% (  23.24%)
Amean  8         87.06  +- 0.28% (  18.02%)       86.77  +- 0.46% (  18.29%)       86.78  +- 0.22% (  18.28%)
Amean  16        48.03  +- 0.93% (  15.68%)       47.75  +- 1.99% (  16.17%)       47.52  +- 1.61% (  16.57%)
Amean  32        30.23  +- 1.20% (  13.14%)       30.08  +- 1.67% (  13.57%)       30.07  +- 1.67% (  13.60%)
Amean  64        22.59  +- 2.02% (  13.50%)       22.63  +- 0.81% (  13.32%)       22.42  +- 0.76% (  14.12%)
Amean  128       21.37  +- 0.67% (  13.82%)       21.31  +- 1.15% (  14.07%)       21.17  +- 1.93% (  14.63%)
Amean  160       21.68  +- 0.57% (  12.76%)       21.18  +- 1.74% (  14.77%)       21.22  +- 1.00% (  14.61%)

The patch outperform active intel_pstate (and baseline) by a considerable
margin; the summary table from the previous section says 4C turbo and active
intel_pstate are 0.83 and 0.93 against baseline respectively, so 4C turbo is
0.83/0.93=0.89 against intel_pstate (~10% better on average). There is no
noticeable difference with regard to the value of freq_max.

Machine            : 8x-SKYLAKE-UMA
Benchmark          : gitsource (time to run the git unit test suite)
Varying parameter  : none
Unit               : seconds (lower is better)

                            5.2.0 vanilla           5.2.0 intel_pstate/hwp         5.2.0 1C-turbo
- - - - - - - -  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean         858.85  +- 1.16% (        )      791.94  +- 0.21% (   7.79%)      474.95 (  44.70%)

                           5.2.0 3C-turbo                   5.2.0 4C-turbo
- - - - - - - -  - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean         475.26  +- 0.20% (  44.66%)      474.34  +- 0.13% (  44.77%)

In this test, which is of interest as representing shell-intensive
(i.e. fork-intensive) serialized workloads, invariant schedutil outperforms
intel_pstate/powersave by a whopping 40% margin.

5.3.4 POWER CONSUMPTION, PERFORMANCE-PER-WATT
---------------------------------------------

The following table shows average power consumption in watt for each
benchmark. Data comes from turbostat (package average), which in turn is read
from the RAPL interface on CPUs. We know the patch affects CPU frequencies so
it's reasonable to ignore other power consumers (such as memory or I/O). Also,
we don't have a power meter available in the lab so RAPL is the best we have.

turbostat sampled average power every 10 seconds for the entire duration of
each benchmark. We took all those values and averaged them (i.e. with don't
have detail on a per-parameter granularity, only on whole benchmarks).

80x-BROADWELL-NUMA (power consumption, watts)
                                                    +--------+
               BASELINE I_PSTATE       1C       3C  |     4C |      8C
pgbench-ro       130.01   142.77   131.11   132.45  | 134.65 |  136.84
pgbench-rw        68.30    60.83    71.45    71.70  |  71.65 |   72.54
dbench4           90.25    59.06   101.43    99.89  | 101.10 |  102.94
netperf-udp       65.70    69.81    66.02    68.03  |  68.27 |   68.95
netperf-tcp       88.08    87.96    88.97    88.89  |  88.85 |   88.20
tbench4          142.32   176.73   153.02   163.91  | 165.58 |  176.07
kernbench         92.94   101.95   114.91   115.47  | 115.52 |  115.10
gitsource         40.92    41.87    75.14    75.20  |  75.40 |   75.70
                                                    +--------+
8x-SKYLAKE-UMA (power consumption, watts)
                                                    +--------+
              BASELINE I_PSTATE/HWP    1C       3C  |     4C |
pgbench-ro        46.49    46.68    46.56    46.59  |  46.52 |
pgbench-rw        29.34    31.38    30.98    31.00  |  31.00 |
dbench4           27.28    27.37    27.49    27.41  |  27.38 |
netperf-udp       22.33    22.41    22.36    22.35  |  22.36 |
netperf-tcp       27.29    27.29    27.30    27.31  |  27.33 |
tbench4           41.13    45.61    43.10    43.33  |  43.56 |
kernbench         42.56    42.63    43.01    43.01  |  43.01 |
gitsource         13.32    13.69    17.33    17.30  |  17.35 |
                                                    +--------+
48x-HASWELL-NUMA (power consumption, watts)
                                                    +--------+
               BASELINE I_PSTATE       1C       3C  |     4C |     12C
pgbench-ro       128.84   136.04   129.87   132.43  | 132.30 |  134.86
pgbench-rw        37.68    37.92    37.17    37.74  |  37.73 |   37.31
dbench4           28.56    28.73    28.60    28.73  |  28.70 |   28.79
netperf-udp       56.70    60.44    56.79    57.42  |  57.54 |   57.52
netperf-tcp       75.49    75.27    75.87    76.02  |  76.01 |   75.95
tbench4          115.44   139.51   119.53   123.07  | 123.97 |  130.22
kernbench         83.23    91.55    95.58    95.69  |  95.72 |   96.04
gitsource         36.79    36.99    39.99    40.34  |  40.35 |   40.23
                                                    +--------+

A lower power consumption isn't necessarily better, it depends on what is done
with that energy. Here are tables with the ratio of performance-per-watt on
each machine and benchmark. Higher is always better; a tilde (~) means a
neutral ratio (i.e. 1.00).

80x-BROADWELL-NUMA (performance-per-watt ratios; higher is better)
                                     +------+
             I_PSTATE     1C     3C  |   4C |    8C
pgbench-ro       1.04   1.06   0.94  | 1.07 |  1.08
pgbench-rw       1.10   0.97   0.96  | 0.96 |  0.97
dbench4          1.24   0.94   0.95  | 0.94 |  0.92
netperf-udp      ~      1.02   1.02  | ~    |  1.02
netperf-tcp      ~      1.02   ~     | ~    |  1.02
tbench4          1.26   1.10   1.06  | 1.12 |  1.26
kernbench        0.98   0.97   0.97  | 0.97 |  0.98
gitsource        ~      1.11   1.11  | 1.11 |  1.13
                                     +------+

8x-SKYLAKE-UMA (performance-per-watt ratios; higher is better)
                                     +------+
         I_PSTATE/HWP     1C     3C  |   4C |
pgbench-ro       ~      ~      ~     | ~    |
pgbench-rw       0.95   0.97   0.96  | 0.96 |
dbench4          ~      ~      ~     | ~    |
netperf-udp      ~      ~      ~     | ~    |
netperf-tcp      ~      ~      ~     | ~    |
tbench4          1.17   1.09   1.08  | 1.10 |
kernbench        ~      ~      ~     | ~    |
gitsource        1.06   1.40   1.40  | 1.40 |
                                     +------+

48x-HASWELL-NUMA  (performance-per-watt ratios; higher is better)
                                     +------+
             I_PSTATE     1C     3C  |   4C |   12C
pgbench-ro       1.09   ~      1.09  | 1.03 |  1.11
pgbench-rw       ~      0.86   ~     | ~    |  0.86
dbench4          ~      1.02   1.02  | 1.02 |  ~
netperf-udp      ~      0.97   1.03  | 1.02 |  ~
netperf-tcp      0.96   ~      ~     | ~    |  ~
tbench4          1.24   ~      1.06  | 1.05 |  1.11
kernbench        0.97   0.97   0.98  | 0.97 |  0.96
gitsource        1.03   1.33   1.32  | 1.32 |  1.33
                                     +------+

These results are overall pleasing: in plenty of cases we observe
performance-per-watt improvements. The few regressions (read/write pgbench and
dbench on the Broadwell machine) are of small magnitude. kernbench loses a few
percentage points (it has a 10-15% performance improvement, but apparently the
increase in power consumption is larger than that). tbench4 and gitsource, which
benefit the most from the patch, keep a positive score in this table which is
a welcome surprise; that suggests that in those particular workloads the
non-invariant schedutil (and active intel_pstate, too) makes some rather
suboptimal frequency selections.

+-------------------------------------------------------------------------+
| 6. MICROARCH'ES ADDRESSED HERE
+-------------------------------------------------------------------------+

The patch addresses Xeon Core processors that use MSR_PLATFORM_INFO and
MSR_TURBO_RATIO_LIMIT to advertise their base frequency and turbo frequencies
respectively. This excludes the recent Xeon Scalable Performance processors
line (Xeon Gold, Platinum etc) whose MSRs have to be parsed differently.

Subsequent patches will address:

* Xeon Scalable Performance processors and Atom Goldmont/Goldmont Plus
* Xeon Phi (Knights Landing, Knights Mill)
* Atom Silvermont

+-------------------------------------------------------------------------+
| 7. REFERENCES
+-------------------------------------------------------------------------+

Tests have been run with the help of the MMTests performance testing
framework, see github.com/gormanm/mmtests. The configuration file names for
the benchmark used are:

    db-pgbench-timed-ro-small-xfs
    db-pgbench-timed-rw-small-xfs
    io-dbench4-async-xfs
    network-netperf-unbound
    network-tbench
    scheduler-unbound
    workload-kerndevel-xfs
    workload-shellscripts-xfs
    hpc-nas-c-class-mpi-full-xfs
    hpc-nas-c-class-omp-full

All those benchmarks are generally available on the web:

pgbench: https://www.postgresql.org/docs/10/pgbench.html
netperf: https://hewlettpackard.github.io/netperf/
dbench/tbench: https://dbench.samba.org/
gitsource: git unit test suite, github.com/git/git
NAS Parallel Benchmarks: https://www.nas.nasa.gov/publications/npb.html
hackbench: https://people.redhat.com/mingo/cfs-scheduler/tools/hackbench.c

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Doug Smythies <dsmythies@telus.net>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-2-ggherdovich@suse.cz
2020-01-28 21:36:59 +01:00
Linus Torvalds
f6170f0afb Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 updates from Ingo Molnar:
 "Misc changes:

   - Enhance #GP fault printouts by distinguishing between canonical and
     non-canonical address faults, and also add KASAN fault decoding.

   - Fix/enhance the x86 NMI handler by putting the duration check into
     a direct function call instead of an irq_work which we know to be
     broken in some cases.

   - Clean up do_general_protection() a bit"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/nmi: Remove irq_work from the long duration NMI handler
  x86/traps: Cleanup do_general_protection()
  x86/kasan: Print original address on #GP
  x86/dumpstack: Introduce die_addr() for die() with #GP fault address
  x86/traps: Print address on #GP
  x86/insn-eval: Add support for 64-bit kernel mode
2020-01-28 12:28:06 -08:00
Linus Torvalds
6da49d1abd Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups all around the map"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/CPU/AMD: Remove amd_get_topology_early()
  x86/tsc: Remove redundant assignment
  x86/crash: Use resource_size()
  x86/cpu: Add a missing prototype for arch_smt_update()
  x86/nospec: Remove unused RSB_FILL_LOOPS
  x86/vdso: Provide missing include file
  x86/Kconfig: Correct spelling and punctuation
  Documentation/x86/boot: Fix typo
  x86/boot: Fix a comment's incorrect file reference
  x86/process: Remove set but not used variables prev and next
  x86/Kconfig: Fix Kconfig indentation
2020-01-28 12:11:23 -08:00
Linus Torvalds
4244057c3d Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 resource control updates from Ingo Molnar:
 "The main change in this tree is the extension of the resctrl procfs
  ABI with a new file that helps tooling to navigate from tasks back to
  resctrl groups: /proc/{pid}/cpu_resctrl_groups.

  Also fix static key usage for certain feature combinations and
  simplify the task exit resctrl case"

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Add task resctrl information display
  x86/resctrl: Check monitoring static key in the MBM overflow handler
  x86/resctrl: Do not reconfigure exiting tasks
2020-01-28 12:00:29 -08:00
Linus Torvalds
6b90e71a47 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot update from Ingo Molnar:
 "Two minor changes: fix an atypical binutils combination build bug, and
  also fix a VRAM size check for simplefb"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sysfb: Fix check for bad VRAM size
  x86/boot: Discard .eh_frame sections
2020-01-28 11:54:05 -08:00
Linus Torvalds
bcc8aff6af Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "Misc updates:

   - Remove last remaining calls to exception_enter/exception_exit() and
     simplify the entry code some more.

   - Remove force_iret()

   - Add support for "Fast Short Rep Mov", which is available starting
     with Ice Lake Intel CPUs - and make the x86 assembly version of
     memmove() use REP MOV for all sizes when FSRM is available.

   - Micro-optimize/simplify the 32-bit boot code a bit.

   - Use a more future-proof SYSRET instruction mnemonic"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Simplify calculation of output address
  x86/entry/64: Add instruction suffix to SYSRET
  x86: Remove force_iret()
  x86/cpufeatures: Add support for fast short REP; MOVSB
  x86/context-tracking: Remove exception_enter/exit() from KVM_PV_REASON_PAGE_NOT_PRESENT async page fault
  x86/context-tracking: Remove exception_enter/exit() from do_page_fault()
2020-01-28 11:08:13 -08:00
Linus Torvalds
435dd727a4 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic fix from Ingo Molnar:
 "A single commit that simplifies the code and gets rid of a compiler
  warning"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic/uv: Avoid unused variable warning
2020-01-28 11:06:49 -08:00
Ingo Molnar
6bd3357b61 Merge branches 'x86/hyperv', 'x86/kdump' and 'x86/misc' into x86/urgent, to pick up single-commit branches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-28 19:08:52 +01:00
Linus Torvalds
c0e809e244 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Kernel side changes:

   - Ftrace is one of the last W^X violators (after this only KLP is
     left). These patches move it over to the generic text_poke()
     interface and thereby get rid of this oddity. This requires a
     surprising amount of surgery, by Peter Zijlstra.

   - x86/AMD PMUs: add support for 'Large Increment per Cycle Events' to
     count certain types of events that have a special, quirky hw ABI
     (by Kim Phillips)

   - kprobes fixes by Masami Hiramatsu

  Lots of tooling updates as well, the following subcommands were
  updated: annotate/report/top, c2c, clang, record, report/top TUI,
  sched timehist, tests; plus updates were done to the gtk ui, libperf,
  headers and the parser"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
  perf/x86/amd: Add support for Large Increment per Cycle Events
  perf/x86/amd: Constrain Large Increment per Cycle events
  perf/x86/intel/rapl: Add Comet Lake support
  tracing: Initialize ret in syscall_enter_define_fields()
  perf header: Use last modification time for timestamp
  perf c2c: Fix return type for histogram sorting comparision functions
  perf beauty sockaddr: Fix augmented syscall format warning
  perf/ui/gtk: Fix gtk2 build
  perf ui gtk: Add missing zalloc object
  perf tools: Use %define api.pure full instead of %pure-parser
  libperf: Setup initial evlist::all_cpus value
  perf report: Fix no libunwind compiled warning break s390 issue
  perf tools: Support --prefix/--prefix-strip
  perf report: Clarify in help that --children is default
  tools build: Fix test-clang.cpp with Clang 8+
  perf clang: Fix build with Clang 9
  kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic
  tools lib: Fix builds when glibc contains strlcpy()
  perf report/top: Make 'e' visible in the help and make it toggle showing callchains
  perf report/top: Do not offer annotation for symbols without samples
  ...
2020-01-28 09:44:15 -08:00
Linus Torvalds
634cd4b6af Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Cleanup of the GOP [graphics output] handling code in the EFI stub

   - Complete refactoring of the mixed mode handling in the x86 EFI stub

   - Overhaul of the x86 EFI boot/runtime code

   - Increase robustness for mixed mode code

   - Add the ability to disable DMA at the root port level in the EFI
     stub

   - Get rid of RWX mappings in the EFI memory map and page tables,
     where possible

   - Move the support code for the old EFI memory mapping style into its
     only user, the SGI UV1+ support code.

   - plus misc fixes, updates, smaller cleanups.

  ... and due to interactions with the RWX changes, another round of PAT
  cleanups make a guest appearance via the EFI tree - with no side
  effects intended"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  efi/x86: Disable instrumentation in the EFI runtime handling code
  efi/libstub/x86: Fix EFI server boot failure
  efi/x86: Disallow efi=old_map in mixed mode
  x86/boot/compressed: Relax sed symbol type regex for LLVM ld.lld
  efi/x86: avoid KASAN false positives when accessing the 1: 1 mapping
  efi: Fix handling of multiple efi_fake_mem= entries
  efi: Fix efi_memmap_alloc() leaks
  efi: Add tracking for dynamically allocated memmaps
  efi: Add a flags parameter to efi_memory_map
  efi: Fix comment for efi_mem_type() wrt absent physical addresses
  efi/arm: Defer probe of PCIe backed efifb on DT systems
  efi/x86: Limit EFI old memory map to SGI UV machines
  efi/x86: Avoid RWX mappings for all of DRAM
  efi/x86: Don't map the entire kernel text RW for mixed mode
  x86/mm: Fix NX bit clearing issue in kernel_map_pages_in_pgd
  efi/libstub/x86: Fix unused-variable warning
  efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed mode
  efi/libstub/x86: Use const attribute for efi_is_64bit()
  efi: Allow disabling PCI busmastering on bridges during boot
  efi/x86: Allow translating 64-bit arguments for mixed mode calls
  ...
2020-01-28 09:03:40 -08:00
Linus Torvalds
8b561778f2 Merge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
 "The main changes are to move the ORC unwind table sorting from early
  init to build-time - this speeds up booting.

  No change in functionality intended"

* 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/unwind/orc: Fix !CONFIG_MODULES build warning
  x86/unwind/orc: Remove boot-time ORC unwind tables sorting
  scripts/sorttable: Implement build-time ORC unwind table sorting
  scripts/sorttable: Rename 'sortextable' to 'sorttable'
  scripts/sortextable: Refactor the do_func() function
  scripts/sortextable: Remove dead code
  scripts/sortextable: Clean up the code to meet the kernel coding style better
  scripts/sortextable: Rewrite error/success handling
2020-01-28 08:38:25 -08:00
Linus Torvalds
9f2a43019e Merge branch 'core-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull header cleanup from Ingo Molnar:
 "This is a treewide cleanup, mostly (but not exclusively) with x86
  impact, which breaks implicit dependencies on the asm/realtime.h
  header and finally removes it from asm/acpi.h"

* 'core-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ACPI/sleep: Move acpi_get_wakeup_address() into sleep.c, remove <asm/realmode.h> from <asm/acpi.h>
  ACPI/sleep: Convert acpi_wakeup_address into a function
  x86/ACPI/sleep: Remove an unnecessary include of asm/realmode.h
  ASoC: Intel: Skylake: Explicitly include linux/io.h for virt_to_phys()
  vmw_balloon: Explicitly include linux/io.h for virt_to_phys()
  virt: vbox: Explicitly include linux/io.h to pick up various defs
  efi/capsule-loader: Explicitly include linux/io.h for page_to_phys()
  perf/x86/intel: Explicitly include asm/io.h to use virt_to_phys()
  x86/kprobes: Explicitly include vmalloc.h for set_vm_flush_reset_perms()
  x86/ftrace: Explicitly include vmalloc.h for set_vm_flush_reset_perms()
  x86/boot: Explicitly include realmode.h to handle RM reservations
  x86/efi: Explicitly include realmode.h to handle RM trampoline quirk
  x86/platform/intel/quark: Explicitly include linux/io.h for virt_to_phys()
  x86/setup: Enhance the comments
  x86/setup: Clean up the header portion of setup.c
2020-01-28 08:20:54 -08:00
Linus Torvalds
b0be0eff1a The performance deterioration departement provides a few non-scary fixes
and improvements:
 
  - Update the cached HLE state when the TSX state is changed via the new
    control register. This ensures feature bit consistency.
 
  - Exclude the new Zhaoxin CPUs from Spectre V2 and SWAPGS vulnerabilities.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl4vc5ITHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoRujEACeWTy4k+eCprV2tu4O/e15VaGaIdRp
 Kdv02kZ1U/3upSubRYW8XsBqesCdbSzfO78fE7yQYZmTbOxczSE1t2XH5Cj7c3ig
 3D4gzXaH2XKf+j9cXceba/3cpRsMU8fAhQYr+Immi/dG2ORs8i2C4G0cxKthqvbP
 R6qdS+Pg9Mo1a2c2nLRGMDyNbNdaYXiJEiWSGNlc6Den/vog+jR4T2WV5a5IjeKL
 yjjukoLoeScJ/3gYK0BQkaGNY3BeU1H5ECtbVM3SBFkp2a9OVGhr1bSxwO1U+T8C
 fdzwJZU/p+JTb69kx91Tz8+wd2zLtV1wxbdZY7nyUUfGd80q0eU4sQZQyY13mONw
 0LRvXrfHjIsRPSiRY3iyHYq9I0UZmjG7oInqRLimLrJmjrPtALhu/mO5TjZbxjzM
 FSVx5fWbZYUgnrQpB+hjqiBcrc3sjjrDwU6DufbSq/AhTBKQ/o0mC+S63OhJ0H7C
 Bzp1m0OniDuNRtYD0LZm0ktAkLpCTy5lgGBQ6ffNqs87ivFi0GTErqml5GrUEKQ5
 mq7h56mf00jKPBYOVoYs9MuWJ18JVJuVNipdlM+P7027XDRpl46l9g87YuMhIol/
 tQsDHB4Dv/1QTZY3K3MuNLFZaQJ4/DI9LA2B1br1PdHbZSDd81NflT6FKE11rqWC
 T+DCpmj+smRqVw==
 =dOgd
 -----END PGP SIGNATURE-----

Merge tag 'x86-pti-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 pti updates from Thomas Gleixner:
 "The performance deterioration departement provides a few non-scary
  fixes and improvements:

   - Update the cached HLE state when the TSX state is changed via the
     new control register. This ensures feature bit consistency.

   - Exclude the new Zhaoxin CPUs from Spectre V2 and SWAPGS
     vulnerabilities"

* tag 'x86-pti-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/speculation/swapgs: Exclude Zhaoxin CPUs from SWAPGS vulnerability
  x86/speculation/spectre_v2: Exclude Zhaoxin CPUs from SPECTRE_V2
  x86/cpu: Update cached HLE state on write to TSX_CTRL_CPUID_CLEAR
2020-01-27 17:28:52 -08:00
Linus Torvalds
e279160f49 The timekeeping and timers departement provides:
- Time namespace support:
 
     If a container migrates from one host to another then it expects that
     clocks based on MONOTONIC and BOOTTIME are not subject to
     disruption. Due to different boot time and non-suspended runtime these
     clocks can differ significantly on two hosts, in the worst case time
     goes backwards which is a violation of the POSIX requirements.
 
     The time namespace addresses this problem. It allows to set offsets for
     clock MONOTONIC and BOOTTIME once after creation and before tasks are
     associated with the namespace. These offsets are taken into account by
     timers and timekeeping including the VDSO.
 
     Offsets for wall clock based clocks (REALTIME/TAI) are not provided by
     this mechanism. While in theory possible, the overhead and code
     complexity would be immense and not justified by the esoteric potential
     use cases which were discussed at Plumbers '18.
 
     The overhead for tasks in the root namespace (host time offsets = 0) is
     in the noise and great effort was made to ensure that especially in the
     VDSO. If time namespace is disabled in the kernel configuration the
     code is compiled out.
 
     Kudos to Andrei Vagin and Dmitry Sofanov who implemented this feature
     and kept on for more than a year addressing review comments, finding
     better solutions. A pleasant experience.
 
   - Overhaul of the alarmtimer device dependency handling to ensure that
     the init/suspend/resume ordering is correct.
 
   - A new clocksource/event driver for Microchip PIT64
 
   - Suspend/resume support for the Hyper-V clocksource
 
   - The usual pile of fixes, updates and improvements mostly in the
     driver code.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl4vbTcTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoXT2D/96iJ3G9Snn2khEQP3XS2rYmtDGw7NO
 m1n96falwWeGe6zreU80R2Jge5nLxQtNhRoMPLLee1GpHwRC6lvqEqgdZ4LMBrD2
 JqV7Gzg8Urmdh+hpDsyTCpeEWEzoMKxiFOX8PxwctqUhM4szEe5iQg2YQsg85Jw2
 vG6M93N2xwDILh4rhEMbKjo+5ZmYn7c1RQvpGOSmpKOj940W/N7H2HBsFhdaJ1Kw
 FW5pFv1211PaU5RV2YNb2dMeeMTT1N3e2VN4Dkadoxp47pb+725gNHEBEjmV9poG
 Lp4IhzGAPnj8zVD88icQZSTaK3gUHMClxprJ0Pf84WEtiH7SeGu8BPYyu77+oNDe
 yzcctDJNyCWXkzmaP/fe/HLc0TStbvNAJ5Tagp4BC75gzebeb4/n8RtRT0fKeDYL
 pxpDPKDAPU7p1JSjxiWAtshqjBycWNY3Z49bA7/VhKBhnv8BDyBPGlYd7/4xrbGr
 RK7DQNXJwaJaiNJ7p5PiaFxGzNyB0B9sThD/slSlEInIKb4h9YzWr0TV+NB62VnB
 sDcN+tpLbRPz5/5cHGGfxR0+zKWpfyai8pzbmmaXEaKssjRYwyvcac5EZdgbWpbK
 k7CqAjoWLA2P+tGeePNJOf5JYK6Vmdyh4clmuwM0zOiRJ9NlWUyMf3z7QYILs4RO
 UAI+6opYlZEPAw==
 =x3qT
 -----END PGP SIGNATURE-----

Merge tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "The timekeeping and timers departement provides:

   - Time namespace support:

     If a container migrates from one host to another then it expects
     that clocks based on MONOTONIC and BOOTTIME are not subject to
     disruption. Due to different boot time and non-suspended runtime
     these clocks can differ significantly on two hosts, in the worst
     case time goes backwards which is a violation of the POSIX
     requirements.

     The time namespace addresses this problem. It allows to set offsets
     for clock MONOTONIC and BOOTTIME once after creation and before
     tasks are associated with the namespace. These offsets are taken
     into account by timers and timekeeping including the VDSO.

     Offsets for wall clock based clocks (REALTIME/TAI) are not provided
     by this mechanism. While in theory possible, the overhead and code
     complexity would be immense and not justified by the esoteric
     potential use cases which were discussed at Plumbers '18.

     The overhead for tasks in the root namespace (ie where host time
     offsets = 0) is in the noise and great effort was made to ensure
     that especially in the VDSO. If time namespace is disabled in the
     kernel configuration the code is compiled out.

     Kudos to Andrei Vagin and Dmitry Sofanov who implemented this
     feature and kept on for more than a year addressing review
     comments, finding better solutions. A pleasant experience.

   - Overhaul of the alarmtimer device dependency handling to ensure
     that the init/suspend/resume ordering is correct.

   - A new clocksource/event driver for Microchip PIT64

   - Suspend/resume support for the Hyper-V clocksource

   - The usual pile of fixes, updates and improvements mostly in the
     driver code"

* tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
  alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n
  alarmtimer: Use wakeup source from alarmtimer platform device
  alarmtimer: Make alarmtimer platform device child of RTC device
  alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect reality
  hrtimer: Add missing sparse annotation for __run_timer()
  lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres()
  MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel
  clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC
  clocksource/drivers/hyper-v: Untangle stimers and timesync from clocksources
  clocksource/drivers/timer-microchip-pit64b: Fix sparse warning
  clocksource/drivers/exynos_mct: Rename Exynos to lowercase
  clocksource/drivers/timer-ti-dm: Fix uninitialized pointer access
  clocksource/drivers/timer-ti-dm: Switch to platform_get_irq
  clocksource/drivers/timer-ti-dm: Convert to devm_platform_ioremap_resource
  clocksource/drivers/em_sti: Fix variable declaration in em_sti_probe
  clocksource/drivers/em_sti: Convert to devm_platform_ioremap_resource
  clocksource/drivers/bcm2835_timer: Fix memory leak of timer
  clocksource/drivers/cadence-ttc: Use ttc driver as platform driver
  clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support
  clocksource/drivers/hyper-v: Reserve PAGE_SIZE space for tsc page
  ...
2020-01-27 16:47:05 -08:00
Linus Torvalds
6a1000bd27 ioremap changes for 5.6
- remove ioremap_nocache given that is is equivalent to
    ioremap everywhere
 -----BEGIN PGP SIGNATURE-----
 
 iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAl4vKHwLHGhjaEBsc3Qu
 ZGUACgkQD55TZVIEUYMPGBAAuVNUZaZfWYHpiVP2oRcUQUguFiD3NTbknsyzV2oH
 J9P0GfeENSKwE9OOhZ7XIjnCZAJwQgTK/ppQY5yiQ/KAtYyyXjXEJ6jqqjiTDInr
 +3+I3t/LhkgrK7tMrb7ylTGa/d7KhaciljnOXC8+b75iddvM9I1z2pbHDbppZMS9
 wT4RXL/cFtRb85AfOyPLybcka3f5P2gGvQz38qyimhJYEzHDXZu9VO1Bd20f8+Xf
 eLBKX0o6yWMhcaPLma8tm0M0zaXHEfLHUKLSOkiOk+eHTWBZ3b/w5nsOQZYZ7uQp
 25yaClbameAn7k5dHajduLGEJv//ZjLRWcN3HJWJ5vzO111aHhswpE7JgTZJSVWI
 ggCVkytD3ESXapvswmACSeCIDMmiJMzvn6JvwuSMVB7a6e5mcqTuGo/FN+DrBF/R
 IP+/gY/T7zIIOaljhQVkiEIIwiD/akYo0V9fheHTBnqcKEDTHV4WjKbeF6aCwcO+
 b8inHyXZSKSMG//UlDuN84/KH/o1l62oKaB1uDIYrrL8JVyjAxctWt3GOt5KgSFq
 wVz1lMw4kIvWtC/Sy2H4oB+RtODLp6yJDqmvmPkeJwKDUcd/1JKf0KsZ8j3FpGei
 /rEkBEss0KBKyFAgBSRO2jIpdj2epgcBcsdB/r5mlhcn8L77AS6mHbA173kY4pQ/
 Kdg=
 =TUCJ
 -----END PGP SIGNATURE-----

Merge tag 'ioremap-5.6' of git://git.infradead.org/users/hch/ioremap

Pull ioremap updates from Christoph Hellwig:
 "Remove the ioremap_nocache API (plus wrappers) that are always
  identical to ioremap"

* tag 'ioremap-5.6' of git://git.infradead.org/users/hch/ioremap:
  remove ioremap_nocache and devm_ioremap_nocache
  MIPS: define ioremap_nocache to ioremap
2020-01-27 13:03:00 -08:00
Linus Torvalds
30f5a75640 Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RAS updates from Borislav Petkov:

 - Misc fixes to the MCE code all over the place, by Jan H. Schönherr.

 - Initial support for AMD F19h and other cleanups to amd64_edac, by
   Yazen Ghannam.

 - Other small cleanups.

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  EDAC/mce_amd: Make fam_ops static global
  EDAC/amd64: Drop some family checks for newer systems
  EDAC/amd64: Add family ops for Family 19h Models 00h-0Fh
  x86/amd_nb: Add Family 19h PCI IDs
  EDAC/mce_amd: Always load on SMCA systems
  x86/MCE/AMD, EDAC/mce_amd: Add new Load Store unit McaType
  x86/mce: Fix use of uninitialized MCE message string
  x86/mce: Fix mce=nobootlog
  x86/mce: Take action on UCNA/Deferred errors again
  x86/mce: Remove mce_inject_log() in favor of mce_log()
  x86/mce: Pass MCE message to mce_panic() on failed kernel recovery
  x86/mce/therm_throt: Mark throttle_active_work() as __maybe_unused
2020-01-27 09:19:35 -08:00
Borislav Petkov
3c749b81ee x86/CPU/AMD: Remove amd_get_topology_early()
... and fold its function body into its single call site.

No functional changes:

  # arch/x86/kernel/cpu/amd.o:

   text    data     bss     dec     hex filename
   5994     385       1    6380    18ec amd.o.before
   5994     385       1    6380    18ec amd.o.after

md5:
   99ec6daa095b502297884e949c520f90  amd.o.before.asm
   99ec6daa095b502297884e949c520f90  amd.o.after.asm

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200123165811.5288-1-bp@alien8.de
2020-01-25 12:59:46 +01:00
Dave Hansen
45fc24e89b x86/mpx: remove MPX from arch/x86
From: Dave Hansen <dave.hansen@linux.intel.com>

MPX is being removed from the kernel due to a lack of support
in the toolchain going forward (gcc).

This removes all the remaining (dead at this point) MPX handling
code remaining in the tree.  The only remaining code is the XSAVE
support for MPX state which is currently needd for KVM to handle
VMs which might use MPX.

Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
2020-01-23 10:41:20 -08:00
Dave Hansen
aa9ccb7b47 x86/mpx: remove bounds exception code
From: Dave Hansen <dave.hansen@linux.intel.com>

MPX is being removed from the kernel due to a lack of support
in the toolchain going forward (gcc).

Remove the other user-visible ABI: signal handling.  This code
should basically have been inactive after the prctl()s were
removed, but there may be some small ABI remnants from this code.
Remove it.

Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
2020-01-23 10:41:15 -08:00
Dave Hansen
3a1255396b x86/alternatives: add missing insn.h include
From: Dave Hansen <dave.hansen@linux.intel.com>

While testing my MPX removal series, Borislav noted compilation
failure with an allnoconfig build.

Turned out to be a missing include of insn.h in alternative.c.
With MPX, it got it implicitly from:

	asm/mmu_context.h -> asm/mpx.h -> asm/insn.h

Fixes: c3d6324f84 ("x86/alternatives: Teach text_poke_bp() to emulate instructions")
Reported-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: x86@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
2020-01-23 10:41:13 -08:00
Mateusz Nosek
4144fddbd3 x86/tsc: Remove redundant assignment
Previously, the assignment to the local variable 'now' took place
before the for loop. The loop is unconditional so it will be entered
at least once. The variable 'now' is reassigned in the loop and is not
used before reassigning. Therefore, the assignment before the loop is
unnecessary and can be removed.

No code changed:

  # arch/x86/kernel/tsc_sync.o:

   text    data     bss     dec     hex filename
   3569     198      44    3811     ee3 tsc_sync.o.before
   3569     198      44    3811     ee3 tsc_sync.o.after

md5:
   36216de29b208edbcd34fed9fe7f7b69  tsc_sync.o.before.asm
   36216de29b208edbcd34fed9fe7f7b69  tsc_sync.o.after.asm

 [ bp: Massage commit message. ]

Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200118171143.25178-1-mateusznosek0@gmail.com
2020-01-22 13:52:42 +01:00
Xiaochen Shen
32ada3b9e0 x86/resctrl: Clean up unused function parameter in mkdir path
Commit

  334b0f4e9b ("x86/resctrl: Fix a deadlock due to inaccurate reference")

changed the argument to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock()
within mkdir_rdt_prepare(). That change resulted in an unused function
parameter to mkdir_rdt_prepare().

Clean up the unused function parameter in mkdir_rdt_prepare() and its
callers rdtgroup_mkdir_mon() and rdtgroup_mkdir_ctrl_mon().

Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1578500886-21771-5-git-send-email-xiaochen.shen@intel.com
2020-01-20 17:00:41 +01:00
Xiaochen Shen
334b0f4e9b x86/resctrl: Fix a deadlock due to inaccurate reference
There is a race condition which results in a deadlock when rmdir and
mkdir execute concurrently:

$ ls /sys/fs/resctrl/c1/mon_groups/m1/
cpus  cpus_list  mon_data  tasks

Thread 1: rmdir /sys/fs/resctrl/c1
Thread 2: mkdir /sys/fs/resctrl/c1/mon_groups/m1

3 locks held by mkdir/48649:
 #0:  (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50
 #1:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c13b>] filename_create+0x7b/0x170
 #2:  (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70

4 locks held by rmdir/48652:
 #0:  (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50
 #1:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c3cf>] do_rmdir+0x13f/0x1e0
 #2:  (&type->i_mutex_dir_key#8){++++}, at: [<ffffffffb4c86d5d>] vfs_rmdir+0x4d/0x120
 #3:  (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70

Thread 1 is deleting control group "c1". Holding rdtgroup_mutex,
kernfs_remove() removes all kernfs nodes under directory "c1"
recursively, then waits for sub kernfs node "mon_groups" to drop active
reference.

Thread 2 is trying to create a subdirectory "m1" in the "mon_groups"
directory. The wrapper kernfs_iop_mkdir() takes an active reference to
the "mon_groups" directory but the code drops the active reference to
the parent directory "c1" instead.

As a result, Thread 1 is blocked on waiting for active reference to drop
and never release rdtgroup_mutex, while Thread 2 is also blocked on
trying to get rdtgroup_mutex.

Thread 1 (rdtgroup_rmdir)   Thread 2 (rdtgroup_mkdir)
(rmdir /sys/fs/resctrl/c1)  (mkdir /sys/fs/resctrl/c1/mon_groups/m1)
-------------------------   -------------------------
                            kernfs_iop_mkdir
                              /*
                               * kn: "m1", parent_kn: "mon_groups",
                               * prgrp_kn: parent_kn->parent: "c1",
                               *
                               * "mon_groups", parent_kn->active++: 1
                               */
                              kernfs_get_active(parent_kn)
kernfs_iop_rmdir
  /* "c1", kn->active++ */
  kernfs_get_active(kn)

  rdtgroup_kn_lock_live
    atomic_inc(&rdtgrp->waitcount)
    /* "c1", kn->active-- */
    kernfs_break_active_protection(kn)
    mutex_lock

  rdtgroup_rmdir_ctrl
    free_all_child_rdtgrp
      sentry->flags = RDT_DELETED

    rdtgroup_ctrl_remove
      rdtgrp->flags = RDT_DELETED
      kernfs_get(kn)
      kernfs_remove(rdtgrp->kn)
        __kernfs_remove
          /* "mon_groups", sub_kn */
          atomic_add(KN_DEACTIVATED_BIAS, &sub_kn->active)
          kernfs_drain(sub_kn)
            /*
             * sub_kn->active == KN_DEACTIVATED_BIAS + 1,
             * waiting on sub_kn->active to drop, but it
             * never drops in Thread 2 which is blocked
             * on getting rdtgroup_mutex.
             */
Thread 1 hangs here ---->
            wait_event(sub_kn->active == KN_DEACTIVATED_BIAS)
            ...
                              rdtgroup_mkdir
                                rdtgroup_mkdir_mon(parent_kn, prgrp_kn)
                                  mkdir_rdt_prepare(parent_kn, prgrp_kn)
                                    rdtgroup_kn_lock_live(prgrp_kn)
                                      atomic_inc(&rdtgrp->waitcount)
                                      /*
                                       * "c1", prgrp_kn->active--
                                       *
                                       * The active reference on "c1" is
                                       * dropped, but not matching the
                                       * actual active reference taken
                                       * on "mon_groups", thus causing
                                       * Thread 1 to wait forever while
                                       * holding rdtgroup_mutex.
                                       */
                                      kernfs_break_active_protection(
                                                               prgrp_kn)
                                      /*
                                       * Trying to get rdtgroup_mutex
                                       * which is held by Thread 1.
                                       */
Thread 2 hangs here ---->             mutex_lock
                                      ...

The problem is that the creation of a subdirectory in the "mon_groups"
directory incorrectly releases the active protection of its parent
directory instead of itself before it starts waiting for rdtgroup_mutex.
This is triggered by the rdtgroup_mkdir() flow calling
rdtgroup_kn_lock_live()/rdtgroup_kn_unlock() with kernfs node of the
parent control group ("c1") as argument. It should be called with kernfs
node "mon_groups" instead. What is currently missing is that the
kn->priv of "mon_groups" is NULL instead of pointing to the rdtgrp.

Fix it by pointing kn->priv to rdtgrp when "mon_groups" is created. Then
it could be passed to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock()
instead. And then it operates on the same rdtgroup structure but handles
the active reference of kernfs node "mon_groups" to prevent deadlock.
The same changes are also made to the "mon_data" directories.

This results in some unused function parameters that will be cleaned up
in follow-up patch as the focus here is on the fix only in support of
backporting efforts.

Fixes: c7d9aac613 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-4-git-send-email-xiaochen.shen@intel.com
2020-01-20 16:57:53 +01:00
Xiaochen Shen
074fadee59 x86/resctrl: Fix use-after-free due to inaccurate refcount of rdtgroup
There is a race condition in the following scenario which results in an
use-after-free issue when reading a monitoring file and deleting the
parent ctrl_mon group concurrently:

Thread 1 calls atomic_inc() to take refcount of rdtgrp and then calls
kernfs_break_active_protection() to drop the active reference of kernfs
node in rdtgroup_kn_lock_live().

In Thread 2, kernfs_remove() is a blocking routine. It waits on all sub
kernfs nodes to drop the active reference when removing all subtree
kernfs nodes recursively. Thread 2 could block on kernfs_remove() until
Thread 1 calls kernfs_break_active_protection(). Only after
kernfs_remove() completes the refcount of rdtgrp could be trusted.

Before Thread 1 calls atomic_inc() and kernfs_break_active_protection(),
Thread 2 could call kfree() when the refcount of rdtgrp (sentry) is 0
instead of 1 due to the race.

In Thread 1, in rdtgroup_kn_unlock(), referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_mondata_show)  Thread 2 (rdtgroup_rmdir)
--------------------------------  -------------------------
rdtgroup_kn_lock_live
  /*
   * kn active protection until
   * kernfs_break_active_protection(kn)
   */
  rdtgrp = kernfs_to_rdtgroup(kn)
                                  rdtgroup_kn_lock_live
                                    atomic_inc(&rdtgrp->waitcount)
                                    mutex_lock
                                  rdtgroup_rmdir_ctrl
                                    free_all_child_rdtgrp
                                      /*
                                       * sentry->waitcount should be 1
                                       * but is 0 now due to the race.
                                       */
                                      kfree(sentry)*[1]
  /*
   * Only after kernfs_remove()
   * completes, the refcount of
   * rdtgrp could be trusted.
   */
  atomic_inc(&rdtgrp->waitcount)
  /* kn->active-- */
  kernfs_break_active_protection(kn)
                                    rdtgroup_ctrl_remove
                                      rdtgrp->flags = RDT_DELETED
                                      /*
                                       * Blocking routine, wait for
                                       * all sub kernfs nodes to drop
                                       * active reference in
                                       * kernfs_break_active_protection.
                                       */
                                      kernfs_remove(rdtgrp->kn)
                                  rdtgroup_kn_unlock
                                    mutex_unlock
                                    atomic_dec_and_test(
                                                &rdtgrp->waitcount)
                                    && (flags & RDT_DELETED)
                                      kernfs_unbreak_active_protection(kn)
                                      kfree(rdtgrp)
  mutex_lock
mon_event_read
rdtgroup_kn_unlock
  mutex_unlock
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [1].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    /* kn->active++ */
    kernfs_unbreak_active_protection(kn)
    kfree(rdtgrp)

Fix it by moving free_all_child_rdtgrp() to after kernfs_remove() in
rdtgroup_rmdir_ctrl() to ensure it has the accurate refcount of rdtgrp.

Fixes: f3cbeacaa0 ("x86/intel_rdt/cqm: Add rmdir support")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-3-git-send-email-xiaochen.shen@intel.com
2020-01-20 16:56:11 +01:00
Xiaochen Shen
b8511ccc75 x86/resctrl: Fix use-after-free when deleting resource groups
A resource group (rdtgrp) contains a reference count (rdtgrp->waitcount)
that indicates how many waiters expect this rdtgrp to exist. Waiters
could be waiting on rdtgroup_mutex or some work sitting on a task's
workqueue for when the task returns from kernel mode or exits.

The deletion of a rdtgrp is intended to have two phases:

  (1) while holding rdtgroup_mutex the necessary cleanup is done and
  rdtgrp->flags is set to RDT_DELETED,

  (2) after releasing the rdtgroup_mutex, the rdtgrp structure is freed
  only if there are no waiters and its flag is set to RDT_DELETED. Upon
  gaining access to rdtgroup_mutex or rdtgrp, a waiter is required to check
  for the RDT_DELETED flag.

When unmounting the resctrl file system or deleting ctrl_mon groups,
all of the subdirectories are removed and the data structure of rdtgrp
is forcibly freed without checking rdtgrp->waitcount. If at this point
there was a waiter on rdtgrp then a use-after-free issue occurs when the
waiter starts running and accesses the rdtgrp structure it was waiting
on.

See kfree() calls in [1], [2] and [3] in these two call paths in
following scenarios:
(1) rdt_kill_sb() -> rmdir_all_sub() -> free_all_child_rdtgrp()
(2) rdtgroup_rmdir() -> rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp()

There are several scenarios that result in use-after-free issue in
following:

Scenario 1:
-----------
In Thread 1, rdtgroup_tasks_write() adds a task_work callback
move_myself(). If move_myself() is scheduled to execute after Thread 2
rdt_kill_sb() is finished, referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_tasks_write)        Thread 2 (rdt_kill_sb)
-------------------------------        ----------------------
rdtgroup_kn_lock_live
  atomic_inc(&rdtgrp->waitcount)
  mutex_lock
rdtgroup_move_task
  __rdtgroup_move_task
    /*
     * Take an extra refcount, so rdtgrp cannot be freed
     * before the call back move_myself has been invoked
     */
    atomic_inc(&rdtgrp->waitcount)
    /* Callback move_myself will be scheduled for later */
    task_work_add(move_myself)
rdtgroup_kn_unlock
  mutex_unlock
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
                                       mutex_lock
                                       rmdir_all_sub
                                         /*
                                          * sentry and rdtgrp are freed
                                          * without checking refcount
                                          */
                                         free_all_child_rdtgrp
                                           kfree(sentry)*[1]
                                         kfree(rdtgrp)*[2]
                                       mutex_unlock
/*
 * Callback is scheduled to execute
 * after rdt_kill_sb is finished
 */
move_myself
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [1] or [2].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    kfree(rdtgrp)

Scenario 2:
-----------
In Thread 1, rdtgroup_tasks_write() adds a task_work callback
move_myself(). If move_myself() is scheduled to execute after Thread 2
rdtgroup_rmdir() is finished, referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_tasks_write)        Thread 2 (rdtgroup_rmdir)
-------------------------------        -------------------------
rdtgroup_kn_lock_live
  atomic_inc(&rdtgrp->waitcount)
  mutex_lock
rdtgroup_move_task
  __rdtgroup_move_task
    /*
     * Take an extra refcount, so rdtgrp cannot be freed
     * before the call back move_myself has been invoked
     */
    atomic_inc(&rdtgrp->waitcount)
    /* Callback move_myself will be scheduled for later */
    task_work_add(move_myself)
rdtgroup_kn_unlock
  mutex_unlock
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
                                       rdtgroup_kn_lock_live
                                         atomic_inc(&rdtgrp->waitcount)
                                         mutex_lock
                                       rdtgroup_rmdir_ctrl
                                         free_all_child_rdtgrp
                                           /*
                                            * sentry is freed without
                                            * checking refcount
                                            */
                                           kfree(sentry)*[3]
                                         rdtgroup_ctrl_remove
                                           rdtgrp->flags = RDT_DELETED
                                       rdtgroup_kn_unlock
                                         mutex_unlock
                                         atomic_dec_and_test(
                                                     &rdtgrp->waitcount)
                                         && (flags & RDT_DELETED)
                                           kfree(rdtgrp)
/*
 * Callback is scheduled to execute
 * after rdt_kill_sb is finished
 */
move_myself
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [3].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    kfree(rdtgrp)

If CONFIG_DEBUG_SLAB=y, Slab corruption on kmalloc-2k can be observed
like following. Note that "0x6b" is POISON_FREE after kfree(). The
corrupted bits "0x6a", "0x64" at offset 0x424 correspond to
waitcount member of struct rdtgroup which was freed:

  Slab corruption (Not tainted): kmalloc-2k start=ffff9504c5b0d000, len=2048
  420: 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkjkkkkkkkkkkk
  Single bit error detected. Probably bad RAM.
  Run memtest86+ or a similar memory test tool.
  Next obj: start=ffff9504c5b0d800, len=2048
  000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

  Slab corruption (Not tainted): kmalloc-2k start=ffff9504c58ab800, len=2048
  420: 6b 6b 6b 6b 64 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkdkkkkkkkkkkk
  Prev obj: start=ffff9504c58ab000, len=2048
  000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

Fix this by taking reference count (waitcount) of rdtgrp into account in
the two call paths that currently do not do so. Instead of always
freeing the resource group it will only be freed if there are no waiters
on it. If there are waiters, the resource group will have its flags set
to RDT_DELETED.

It will be left to the waiter to free the resource group when it starts
running and finding that it was the last waiter and the resource group
has been removed (rdtgrp->flags & RDT_DELETED) since. (1) rdt_kill_sb()
-> rmdir_all_sub() -> free_all_child_rdtgrp() (2) rdtgroup_rmdir() ->
rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp()

Fixes: f3cbeacaa0 ("x86/intel_rdt/cqm: Add rmdir support")
Fixes: 60cf5e101f ("x86/intel_rdt: Add mkdir to resctrl file system")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-2-git-send-email-xiaochen.shen@intel.com
2020-01-20 16:45:43 +01:00
Tony W Wang-oc
283bab9809 x86/cpu: Remove redundant cpu_detect_cache_sizes() call
Both functions call init_intel_cacheinfo() which computes L2 and L3 cache
sizes from CPUID(4). But then they also call cpu_detect_cache_sizes() a
bit later which computes ->x86_tlbsize and L2 size from CPUID(80000006).

However, the latter call is not needed because

 - on these CPUs, CPUID(80000006).EBX for ->x86_tlbsize is reserved

 - CPUID(80000006).ECX for the L2 size has the same result as CPUID(4)

Therefore, remove the latter call to simplify the code.

 [ bp: Rewrite commit message. ]

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1579075257-6985-1-git-send-email-TonyWWang-oc@zhaoxin.com
2020-01-20 16:32:35 +01:00
Chen Yu
e79f15a459 x86/resctrl: Add task resctrl information display
Monitoring tools that want to find out which resctrl control and monitor
groups a task belongs to must currently read the "tasks" file in every
group until they locate the process ID.

Add an additional file /proc/{pid}/cpu_resctrl_groups to provide this
information:

1)   res:
     mon:

resctrl is not available.

2)   res:/
     mon:

Task is part of the root resctrl control group, and it is not associated
to any monitor group.

3)  res:/
    mon:mon0

Task is part of the root resctrl control group and monitor group mon0.

4)  res:group0
    mon:

Task is part of resctrl control group group0, and it is not associated
to any monitor group.

5) res:group0
   mon:mon1

Task is part of resctrl control group group0 and monitor group mon1.

Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Jinshi Chen <jinshi.chen@intel.com>
Link: https://lkml.kernel.org/r/20200115092851.14761-1-yu.c.chen@intel.com
2020-01-20 16:19:10 +01:00
Arvind Sankar
dacc909233 x86/sysfb: Fix check for bad VRAM size
When checking whether the reported lfb_size makes sense, the height
* stride result is page-aligned before seeing whether it exceeds the
reported size.

This doesn't work if height * stride is not an exact number of pages.
For example, as reported in the kernel bugzilla below, an 800x600x32 EFI
framebuffer gets skipped because of this.

Move the PAGE_ALIGN to after the check vs size.

Reported-by: Christopher Head <chead@chead.ca>
Tested-by: Christopher Head <chead@chead.ca>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206051
Link: https://lkml.kernel.org/r/20200107230410.2291947-1-nivedita@alum.mit.edu
2020-01-20 10:57:53 +01:00
Ingo Molnar
cb6c82df68 Linux 5.5-rc7
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl4k7i8eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGvk0IAKRenVOdiudY77SQ
 VZjsteyrYTTQtPPv494ToIRjR0XQ+gYp8vyWzXTUC5Nm9Y9U3VzDqUPUjWszrSXE
 6mU+tzcMc9qwuUxnIFn8zfg64ygw+37sn/w3xqeH4QmF9Z5Wl3EX3SdXTs7jp3RS
 VxiztkUNI5ZBV2GDtla5K/9qLPqCQnUYXIiyi5lAtBtiitZDVXFp7dy7hMgEiaEO
 +78K5Kh3xlt5ndDsBFOlwIb2Oof3KL7bBXntdbSBc/bjol6IRvAgln48HWCv59G2
 jzAp2tj2KobX9GRAEPj+v4TQZEW0SXDNDi8MgQsM+3DYVCTmANsv57CBKRuf01+F
 nB1kAys=
 =zSnJ
 -----END PGP SIGNATURE-----

Merge tag 'v5.5-rc7' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-20 08:43:44 +01:00
Ard Biesheuvel
1f299fad1e efi/x86: Limit EFI old memory map to SGI UV machines
We carry a quirk in the x86 EFI code to switch back to an older
method of mapping the EFI runtime services memory regions, because
it was deemed risky at the time to implement a new method without
providing a fallback to the old method in case problems arose.

Such problems did arise, but they appear to be limited to SGI UV1
machines, and so these are the only ones for which the fallback gets
enabled automatically (via a DMI quirk). The fallback can be enabled
manually as well, by passing efi=old_map, but there is very little
evidence that suggests that this is something that is being relied
upon in the field.

Given that UV1 support is not enabled by default by the distros
(Ubuntu, Fedora), there is no point in carrying this fallback code
all the time if there are no other users. So let's move it into the
UV support code, and document that efi=old_map now requires this
support code to be enabled.

Note that efi=old_map has been used in the past on other SGI UV
machines to work around kernel regressions in production, so we
keep the option to enable it by hand, but only if the kernel was
built with UV support.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200113172245.27925-8-ardb@kernel.org
2020-01-20 08:13:01 +01:00
Ingo Molnar
a786810cc8 Linux 5.5-rc7
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl4k7i8eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGvk0IAKRenVOdiudY77SQ
 VZjsteyrYTTQtPPv494ToIRjR0XQ+gYp8vyWzXTUC5Nm9Y9U3VzDqUPUjWszrSXE
 6mU+tzcMc9qwuUxnIFn8zfg64ygw+37sn/w3xqeH4QmF9Z5Wl3EX3SdXTs7jp3RS
 VxiztkUNI5ZBV2GDtla5K/9qLPqCQnUYXIiyi5lAtBtiitZDVXFp7dy7hMgEiaEO
 +78K5Kh3xlt5ndDsBFOlwIb2Oof3KL7bBXntdbSBc/bjol6IRvAgln48HWCv59G2
 jzAp2tj2KobX9GRAEPj+v4TQZEW0SXDNDi8MgQsM+3DYVCTmANsv57CBKRuf01+F
 nB1kAys=
 =zSnJ
 -----END PGP SIGNATURE-----

Merge tag 'v5.5-rc7' into efi/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-20 08:05:16 +01:00
Linus Torvalds
0cc2682d8b Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - a resctrl fix for uninitialized objects found by debugobjects

   - a resctrl memory leak fix

   - fix the unintended re-enabling of the of SME and SEV CPU flags if
     memory encryption was disabled at bootup via the MSR space"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained
  x86/resctrl: Fix potential memory leak
  x86/resctrl: Fix an imbalance in domain_remove_cpu()
2020-01-18 13:02:12 -08:00
Xiaochen Shen
536a0d8e79 x86/resctrl: Check monitoring static key in the MBM overflow handler
Currently, there are three static keys in the resctrl file system:
rdt_mon_enable_key and rdt_alloc_enable_key indicate if the monitoring
feature and the allocation feature are enabled, respectively. The
rdt_enable_key is enabled when either the monitoring feature or the
allocation feature is enabled.

If no monitoring feature is present (either hardware doesn't support a
monitoring feature or the feature is disabled by the kernel command line
option "rdt="), rdt_enable_key is still enabled but rdt_mon_enable_key
is disabled.

MBM is a monitoring feature. The MBM overflow handler intends to
check if the monitoring feature is not enabled for fast return.

So check the rdt_mon_enable_key in it instead of the rdt_enable_key as
former is the more accurate check.

 [ bp: Massage commit message. ]

Fixes: e33026831b ("x86/intel_rdt/mbm: Handle counter overflow")
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1576094705-13660-1-git-send-email-xiaochen.shen@intel.com
2020-01-17 19:32:32 +01:00
Tony W Wang-oc
a84de2fa96 x86/speculation/swapgs: Exclude Zhaoxin CPUs from SWAPGS vulnerability
New Zhaoxin family 7 CPUs are not affected by the SWAPGS vulnerability. So
mark these CPUs in the cpu vulnerability whitelist accordingly.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1579227872-26972-3-git-send-email-TonyWWang-oc@zhaoxin.com
2020-01-17 19:13:47 +01:00
Tony W Wang-oc
1e41a766c9 x86/speculation/spectre_v2: Exclude Zhaoxin CPUs from SPECTRE_V2
New Zhaoxin family 7 CPUs are not affected by SPECTRE_V2. So define a
separate cpu_vuln_whitelist bit NO_SPECTRE_V2 and add these CPUs to the cpu
vulnerability whitelist.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1579227872-26972-2-git-send-email-TonyWWang-oc@zhaoxin.com
2020-01-17 19:13:47 +01:00
Pawan Gupta
5efc6fa904 x86/cpu: Update cached HLE state on write to TSX_CTRL_CPUID_CLEAR
/proc/cpuinfo currently reports Hardware Lock Elision (HLE) feature to
be present on boot cpu even if it was disabled during the bootup. This
is because cpuinfo_x86->x86_capability HLE bit is not updated after TSX
state is changed via the new MSR IA32_TSX_CTRL.

Update the cached HLE bit also since it is expected to change after an
update to CPUID_CLEAR bit in MSR IA32_TSX_CTRL.

Fixes: 95c5824f75 ("x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default")
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/2529b99546294c893dfa1c89e2b3e46da3369a59.1578685425.git.pawan.kumar.gupta@linux.intel.com
2020-01-17 19:13:46 +01:00
Arnd Bergmann
d0b7788804 x86/apic/uv: Avoid unused variable warning
When CONFIG_PROC_FS is disabled, the compiler warns about an unused
variable:

arch/x86/kernel/apic/x2apic_uv_x.c: In function 'uv_setup_proc_files':
arch/x86/kernel/apic/x2apic_uv_x.c:1546:8: error: unused variable 'name' [-Werror=unused-variable]
  char *name = hubless ? "hubless" : "hubbed";

Simplify the code so this variable is no longer needed.

Fixes: 8785968bce ("x86/platform/uv: Add UV Hubbed/Hubless Proc FS Files")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191212140419.315264-1-arnd@arndb.de
2020-01-17 14:34:41 +01:00
Tom Lendacky
a006483b2f x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained
If the SME and SEV features are present via CPUID, but memory encryption
support is not enabled (MSR 0xC001_0010[23]), the feature flags are cleared
using clear_cpu_cap(). However, if get_cpu_cap() is later called, these
feature flags will be reset back to present, which is not desired.

Change from using clear_cpu_cap() to setup_clear_cpu_cap() so that the
clearing of the flags is maintained.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.16.x-
Link: https://lkml.kernel.org/r/226de90a703c3c0be5a49565047905ac4e94e8f3.1579125915.git.thomas.lendacky@amd.com
2020-01-16 20:23:20 +01:00
Yazen Ghannam
b3f79ae459 x86/amd_nb: Add Family 19h PCI IDs
Add the new PCI Device 18h IDs for AMD Family 19h systems. Note that
Family 19h systems will not have a new PCI root device ID.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200110015651.14887-4-Yazen.Ghannam@amd.com
2020-01-16 17:09:18 +01:00
Yazen Ghannam
89a76171bf x86/MCE/AMD, EDAC/mce_amd: Add new Load Store unit McaType
Add support for a new version of the Load Store unit bank type as
indicated by its McaType value, which will be present in future SMCA
systems.

Add the new (HWID, MCATYPE) tuple. Reuse the same name, since this is
logically the same to the user.

Also, add the new error descriptions to edac_mce_amd.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200110015651.14887-2-Yazen.Ghannam@amd.com
2020-01-16 17:09:02 +01:00
Sean Christopherson
bb02e2cb71 x86/cpu: Print "VMX disabled" error message iff KVM is enabled
Don't print an error message about VMX being disabled by BIOS if KVM,
the sole user of VMX, is disabled. E.g. if KVM is disabled and the MSR
is unlocked, the kernel will intentionally disable VMX when locking
feature control and then complain that "BIOS" disabled VMX.

Fixes: ef4d3bf198 ("x86/cpu: Clear VMX feature flag if VMX is not fully enabled")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200114202545.20296-1-sean.j.christopherson@intel.com
2020-01-15 13:26:50 +01:00
Chuansheng Liu
978370956d x86/mce/therm_throt: Do not access uninitialized therm_work
It is relatively easy to trigger the following boot splat on an Ice Lake
client platform. The call stack is like:

  kernel BUG at kernel/timer/timer.c:1152!

  Call Trace:
  __queue_delayed_work
  queue_delayed_work_on
  therm_throt_process
  intel_thermal_interrupt
  ...

The reason is that a CPU's thermal interrupt is enabled prior to
executing its hotplug onlining callback which will initialize the
throttling workqueues.

Such a race can lead to therm_throt_process() accessing an uninitialized
therm_work, leading to the above BUG at a very early bootup stage.

Therefore, unmask the thermal interrupt vector only after having setup
the workqueues completely.

 [ bp: Heavily massage commit message and correct comment formatting. ]

Fixes: f6656208f0 ("x86/mce/therm_throt: Optimize notifications of thermal throttle")
Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200107004116.59353-1-chuansheng.liu@intel.com
2020-01-15 11:31:33 +01:00
Arvind Sankar
2f1e1d8ba4 arch/x86/setup: Drop dummy_con initialization
con_init in tty/vt.c will now set conswitchp to dummy_con if it's unset.
Drop it from arch setup code.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20191218214506.49252-24-nivedita@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 15:29:19 +01:00
Dmitry Safonov
64b302ab66 x86/vdso: Provide vdso_data offset on vvar_page
VDSO support for time namespaces needs to set up a page with the same
layout as VVAR. That timens page will be placed on position of VVAR page
inside namespace. That page has vdso_data->seq set to 1 to enforce
the slow path and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce
the time namespace handling path.

To prepare the time namespace page the kernel needs to know the vdso_data
offset.  Provide arch_get_vdso_data() helper for locating vdso_data on VVAR
page.

Co-developed-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-22-dima@arista.com
2020-01-14 12:20:57 +01:00
Sean Christopherson
85c17291e2 x86/cpufeatures: Add flag to track whether MSR IA32_FEAT_CTL is configured
Add a new feature flag, X86_FEATURE_MSR_IA32_FEAT_CTL, to track whether
IA32_FEAT_CTL has been initialized.  This will allow KVM, and any future
subsystems that depend on IA32_FEAT_CTL, to rely purely on cpufeatures
to query platform support, e.g. allows a future patch to remove KVM's
manual IA32_FEAT_CTL MSR checks.

Various features (on platforms that support IA32_FEAT_CTL) are dependent
on IA32_FEAT_CTL being configured and locked, e.g. VMX and LMCE.  The
MSR is always configured during boot, but only if the CPU vendor is
recognized by the kernel.  Because CPUID doesn't incorporate the current
IA32_FEAT_CTL value in its reporting of relevant features, it's possible
for a feature to be reported as supported in cpufeatures but not truly
enabled, e.g. if the CPU supports VMX but the kernel doesn't recognize
the CPU.

As a result, without the flag, KVM would see VMX as supported even if
IA32_FEAT_CTL hasn't been initialized, and so would need to manually
read the MSR and check the various enabling bits to avoid taking an
unexpected #GP on VMXON.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-14-sean.j.christopherson@intel.com
2020-01-13 18:49:00 +01:00
Sean Christopherson
167a4894c1 x86/cpu: Set synthetic VMX cpufeatures during init_ia32_feat_ctl()
Set the synthetic VMX cpufeatures, which need to be kept to preserve
/proc/cpuinfo's ABI, in the common IA32_FEAT_CTL initialization code.
Remove the vendor code that manually sets the synthetic flags.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-13-sean.j.christopherson@intel.com
2020-01-13 18:43:19 +01:00
Sean Christopherson
14442a159c x86/cpu: Print VMX flags in /proc/cpuinfo using VMX_FEATURES_*
Add support for generating VMX feature names in capflags.c and use the
resulting x86_vmx_flags to print the VMX flags in /proc/cpuinfo.  Don't
print VMX flags if no bits are set in word 0, which holds Pin Controls.
Pin Control's INTR and NMI exiting are fundamental pillars of VMX, if
they are not supported then the CPU is broken, it does not actually
support VMX, or the kernel wasn't built with support for the target CPU.

Print the features in a dedicated "vmx flags" line to avoid polluting
the common "flags" and to avoid having to prefix all flags with "vmx_",
which results in horrendously long names.

Keep synthetic VMX flags in cpufeatures to preserve /proc/cpuinfo's ABI
for those flags.  This means that "flags" and "vmx flags" will have
duplicate entries for tpr_shadow (virtual_tpr), vnmi, ept, flexpriority,
vpid and ept_ad, but caps the pollution of "flags" at those six VMX
features.  The vendor-specific code that populates the synthetic flags
will be consolidated in a future patch to further minimize the lasting
damage.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-12-sean.j.christopherson@intel.com
2020-01-13 18:36:02 +01:00
Sean Christopherson
b47ce1fed4 x86/cpu: Detect VMX features on Intel, Centaur and Zhaoxin CPUs
Add an entry in struct cpuinfo_x86 to track VMX capabilities and fill
the capabilities during IA32_FEAT_CTL MSR initialization.

Make the VMX capabilities dependent on IA32_FEAT_CTL and
X86_FEATURE_NAMES so as to avoid unnecessary overhead on CPUs that can't
possibly support VMX, or when /proc/cpuinfo is not available.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-11-sean.j.christopherson@intel.com
2020-01-13 18:02:53 +01:00
Sean Christopherson
ef4d3bf198 x86/cpu: Clear VMX feature flag if VMX is not fully enabled
Now that IA32_FEAT_CTL is always configured and locked for CPUs that are
known to support VMX[*], clear the VMX capability flag if the MSR is
unsupported or BIOS disabled VMX, i.e. locked IA32_FEAT_CTL and didn't
set the appropriate VMX enable bit.

[*] Because init_ia32_feat_ctl() is called from vendors ->c_init(), it's
    still possible for IA32_FEAT_CTL to be left unlocked when VMX is
    supported by the CPU.  This is not fatal, and will be addressed in a
    future patch.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-9-sean.j.christopherson@intel.com
2020-01-13 17:53:57 +01:00