There are three usercopy warnings which are currently being silenced for
gcc 4.6 and newer:
1) "copy_from_user() buffer size is too small" compile warning/error
This is a static warning which happens when object size and copy size
are both const, and copy size > object size. I didn't see any false
positives for this one. So the function warning attribute seems to
be working fine here.
Note this scenario is always a bug and so I think it should be
changed to *always* be an error, regardless of
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS.
2) "copy_from_user() buffer size is not provably correct" compile warning
This is another static warning which happens when I enable
__compiletime_object_size() for new compilers (and
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS). It happens when object size
is const, but copy size is *not*. In this case there's no way to
compare the two at build time, so it gives the warning. (Note the
warning is a byproduct of the fact that gcc has no way of knowing
whether the overflow function will be called, so the call isn't dead
code and the warning attribute is activated.)
So this warning seems to only indicate "this is an unusual pattern,
maybe you should check it out" rather than "this is a bug".
I get 102(!) of these warnings with allyesconfig and the
__compiletime_object_size() gcc check removed. I don't know if there
are any real bugs hiding in there, but from looking at a small
sample, I didn't see any. According to Kees, it does sometimes find
real bugs. But the false positive rate seems high.
3) "Buffer overflow detected" runtime warning
This is a runtime warning where object size is const, and copy size >
object size.
All three warnings (both static and runtime) were completely disabled
for gcc 4.6 with the following commit:
2fb0815c9e ("gcc4: disable __compiletime_object_size for GCC 4.6+")
That commit mistakenly assumed that the false positives were caused by a
gcc bug in __compiletime_object_size(). But in fact,
__compiletime_object_size() seems to be working fine. The false
positives were instead triggered by #2 above. (Though I don't have an
explanation for why the warnings supposedly only started showing up in
gcc 4.6.)
So remove warning #2 to get rid of all the false positives, and re-enable
warnings #1 and #3 by reverting the above commit.
Furthermore, since #1 is a real bug which is detected at compile time,
upgrade it to always be an error.
Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer
needed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fix from Thomas Gleixner:
"A single bugfix to prevent irq remapping when the ioapic is disabled"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Do not init irq remapping if ioapic is disabled
** fixes for ITS init issues, error handling, IRQ leakage, race conditions
** An erratum workaround for timers
** Some removal of misleading use of errors and comments
** A fix for GICv3 on 32-bit guests
* MIPS fix where the guest could wrongly map the first page of physical memory
* x86 nested virtualization fixes
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJXtyfVAAoJEL/70l94x66Dhe4IAIOGI/OYVWU5IfUQ01oeRgD3
7wN222OmyC/K0/hSZc7ndRdcQfr5ombgM9XsS/EbkcRacWxAUHDX2FaYMpKgjT2M
Dnh2tJHuPz/4VtByGQ2fZ4hziK7amn18/MtPFCee+mIj0ya2fcWZ4qHVU8pKC6Ps
mVVZ0kxXsdV4pw9y6XgBLz/4bTLeASKvhFZrWOnjJoa+GeH2MFwocS0xaEI0HwxP
HVwcgoRdGXJuKUB9jE9FDWmWOgdoLnCG1bNUOvXKPcE0ZaFQDT4I4dImkBys3rqz
jbqnhLrpGEY2ZC3Rj+VyD2MOXbYOOSi59GRwYmCkqD96ZarHxSu3PdyCxmIFWzM=
=+4WK
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"ARM:
- fixes for ITS init issues, error handling, IRQ leakage, race
conditions
- an erratum workaround for timers
- some removal of misleading use of errors and comments
- a fix for GICv3 on 32-bit guests
MIPS:
- fix for where the guest could wrongly map the first page of
physical memory
x86:
- nested virtualization fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
MIPS: KVM: Check for pfn noslot case
kvm: nVMX: fix nested tsc scaling
KVM: nVMX: postpone VMCS changes on MSR_IA32_APICBASE write
KVM: nVMX: fix msr bitmaps to prevent L2 from accessing L0 x2APIC
arm64: KVM: report configured SRE value to 32-bit world
arm64: KVM: remove misleading comment on pmu status
KVM: arm/arm64: timer: Workaround misconfigured timer interrupt
arm64: Document workaround for Cortex-A72 erratum #853709
KVM: arm/arm64: Change misleading use of is_error_pfn
KVM: arm64: ITS: avoid re-mapping LPIs
KVM: arm64: check for ITS device on MSI injection
KVM: arm64: ITS: move ITS registration into first VCPU run
KVM: arm64: vgic-its: Make updates to propbaser/pendbaser atomic
KVM: arm64: vgic-its: Plug race in vgic_put_irq
KVM: arm64: vgic-its: Handle errors from vgic_add_lpi
KVM: arm64: ITS: return 1 on successful MSI injection
Commit 97f2645f35 ("tree-wide: replace config_enabled() with
IS_ENABLED()") mostly killed config_enabled(), but some new users have
appeared for v4.8-rc1. They are all used for a boolean option, so can
be replaced with IS_ENABLED() safely.
Link: http://lkml.kernel.org/r/1471970749-24867-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fix a regression in the xenbus device preventing userspace tools
from working.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXvdugAAoJEFxbo/MsZsTRAwEH/AiKLV4T0OiARv/df827WVnL
obUmEAh/wVSWZh2xdUNurDOH64lEfeBDSBIpGPQMLGmXLzNEQO9u8ZJYWJ7R1Ryp
JU37lu3DP7HqQqTXsy8ltgcBkwVaQZAo0GRtDeua80ZPdjulnZirwHWS48TuNIFF
pVtW4Eoy1BNAVri55o5hOIub4HUKMRoNB/J+o+SKLyJEvOon+qD4pOfIhR3sqeja
oYVX7QpY/4Miymd5uI9v8LUefS4PW/U58a7tjr414Ng4mzQbZOHDmNyWF0CH27lj
INAmgMXDG7RtiSQMWPKtDQUvuefApKoeRmFr6mQ/xHyCX3cAzOw07+p0rKacCig=
=PTX1
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.8b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen regression fix from David Vrabel:
"Fix a regression in the xenbus device preventing userspace tools from
working"
* tag 'for-linus-4.8b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: change the type of xen_vcpu_id to uint32_t
xenbus: don't look up transaction IDs for ordinary writes
We pass xen_vcpu_id mapping information to hypercalls which require
uint32_t type so it would be cleaner to have it as uint32_t. The
initializer to -1 can be dropped as we always do the mapping before using
it and we never check the 'not set' value anyway.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
native_smp_prepare_cpus
-> default_setup_apic_routing
-> enable_IR_x2apic
-> irq_remapping_prepare
-> intel_prepare_irq_remapping
-> intel_setup_irq_remapping
So IR table is setup even if "noapic" boot parameter is added. As a result we
crash later when the interrupt affinity is set due to a half initialized
remapping infrastructure.
Prevent remap initialization when IOAPIC is disabled.
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Link: http://lkml.kernel.org/r/1471954039-3942-1-git-send-email-wanpeng.li@hotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We can't initialize the list head on deletion as this causes the node to
point to itself, which causes an infinite loop if vmd_irq() happens to be
servicing that node.
The list initialization was trying to fix a bug from multiple calls to
disable the same IRQ. Fix this instead by having the VMD driver track if
the interrupt is enabled.
[bhelgaas: changelog, add "Fixes"]
Fixes: 97e9230635 ("x86/PCI: VMD: Initialize list item in IRQ disable")
Reported-by: Grzegorz Koczot <grzegorz.koczot@intel.com>
Tested-by: Miroslaw Drost <miroslaw.drost@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Pull crypto fixes from Herbert Xu:
"This fixes a number of memory corruption bugs in the newly added
sha256-mb/sha256-mb code"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: sha512-mb - fix ctx pointer
crypto: sha256-mb - fix ctx pointer and digest copy
Pull x86 fixes from Ingo Molnar:
"An initrd microcode loading fix, and an SMP bootup topology setup fix
to resolve crashes on SGI/UV systems if the BIOS is configured in a
certain way"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/smp: Fix __max_logical_packages value setup
x86/microcode/AMD: Fix initrd loading with CONFIG_RANDOMIZE_MEMORY=y
When the host supported TSC scaling, L2 would use a TSC multiplier of
0, which causes a VM entry failure. Now L2's TSC uses the same
multiplier as L1.
Signed-off-by: Peter Feiner <pfeiner@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If vmcs12 does not intercept APIC_BASE writes, then KVM will handle the
write with vmcs02 as the current VMCS.
This will incorrectly apply modifications intended for vmcs01 to vmcs02
and L2 can use it to gain access to L0's x2APIC registers by disabling
virtualized x2APIC while using msr bitmap that assumes enabled.
Postpone execution of vmx_set_virtual_x2apic_mode until vmcs01 is the
current VMCS. An alternative solution would temporarily make vmcs01 the
current VMCS, but it requires more care.
Fixes: 8d14695f95 ("x86, apicv: add virtual x2apic support")
Reported-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
msr bitmap can be used to avoid a VM exit (interception) on guest MSR
accesses. In some configurations of VMX controls, the guest can even
directly access host's x2APIC MSRs. See SDM 29.5 VIRTUALIZING MSR-BASED
APIC ACCESSES.
L2 could read all L0's x2APIC MSRs and write TPR, EOI, and SELF_IPI.
To do so, L1 would first trick KVM to disable all possible interceptions
by enabling APICv features and then would turn those features off;
nested_vmx_merge_msr_bitmap() only disabled interceptions, so VMX would
not intercept previously enabled MSRs even though they were not safe
with the new configuration.
Correctly re-enabling interceptions is not enough as a second bug would
still allow L1+L2 to access host's MSRs: msr bitmap was shared for all
VMCSs, so L1 could trigger a race to get the desired combination of msr
bitmap and VMX controls.
This fix allocates a msr bitmap for every L1 VCPU, allows only safe
x2APIC MSRs from L1's msr bitmap, and disables msr bitmaps if they would
have to intercept everything anyway.
Fixes: 3af18d9c5f ("KVM: nVMX: Prepare for using hardware MSR bitmap")
Reported-by: Jim Mattson <jmattson@google.com>
Suggested-by: Wincy Van <fanwenyi0529@gmail.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Frank reported kernel panic when he disabled several cores in BIOS
via following option:
Core Disable Bitmap(Hex) [0]
with number 0xFFE, which leaves 16 CPUs in system (out of 48).
The kernel panic below goes along with following messages:
smpboot: Max logical packages: 2^M
smpboot: APIC(0) Converting physical 0 to logical package 0^M
smpboot: APIC(20) Converting physical 1 to logical package 1^M
smpboot: APIC(40) Package 2 exceeds logical package map^M
smpboot: CPU 8 APICId 40 disabled^M
smpboot: APIC(60) Package 3 exceeds logical package map^M
smpboot: CPU 12 APICId 60 disabled^M
...
general protection fault: 0000 [#1] SMP^M
Modules linked in:^M
CPU: 15 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc5+ #1^M
Hardware name: SGI UV300/UV300, BIOS SGI UV 300 series BIOS 05/25/2016^M
task: ffff8801673e0000 ti: ffff8801673ac000 task.ti: ffff8801673ac000^M
RIP: 0010:[<ffffffff81014d54>] [<ffffffff81014d54>] uncore_change_context+0xd4/0x180^M
...
[<ffffffff810158ac>] uncore_event_init_cpu+0x6c/0x70^M
[<ffffffff81d8c91c>] intel_uncore_init+0x1c2/0x2dd^M
[<ffffffff81d8c75a>] ? uncore_cpu_setup+0x17/0x17^M
[<ffffffff81002190>] do_one_initcall+0x50/0x190^M
[<ffffffff810ab193>] ? parse_args+0x293/0x480^M
[<ffffffff81d87365>] kernel_init_freeable+0x1a5/0x249^M
[<ffffffff81d86a35>] ? set_debug_rodata+0x12/0x12^M
[<ffffffff816dc19e>] kernel_init+0xe/0x110^M
[<ffffffff816e93bf>] ret_from_fork+0x1f/0x40^M
[<ffffffff816dc190>] ? rest_init+0x80/0x80^M
The reason for the panic is wrong value of __max_logical_packages,
which lets logical_package_map uninitialized and the uncore code
relying on this map being properly initialized (maybe we should
add some safety checks there as well).
The __max_logical_packages is computed as:
DIV_ROUND_UP(total_cpus, ncpus);
- ncpus being number of cores
With above BIOS setup we get total_cpus == 16 which set
__max_logical_packages to 2 (ncpus is 12).
Once topology_update_package_map processes CPU with logical
pkg over 2 we display above messages and fail to initialize
the physical_to_logical_pkg map, which makes the uncore code
crash.
The fix is to remove logical_package_map bitmap completely
and keep and update the logical_packages number instead.
After we enumerate all the present CPUs, we check if the
enumerated logical packages count is within its computed
maximum from BIOS data.
If it's not the case, we set this maximum to the new enumerated
value and freeze any new addition of logical packages.
The freeze is because lot of init code like uncore/rapl/cqm
depends on having maximum logical package value set to allocate
their data, so we can't change it later on.
Prarit Bhargava tested the patch and confirms that it solves
the problem:
From dmidecode:
Core Count: 24
Core Enabled: 24
Thread Count: 48
Orig kernel boot log:
[ 0.464981] smpboot: Max logical packages: 19
[ 0.469861] smpboot: APIC(0) Converting physical 0 to logical package 0
[ 0.477261] smpboot: APIC(40) Converting physical 1 to logical package 1
[ 0.484760] smpboot: APIC(80) Converting physical 2 to logical package 2
[ 0.492258] smpboot: APIC(c0) Converting physical 3 to logical package 3
1. nr_cpus=8, should stop enumerating in package 0:
[ 0.533664] smpboot: APIC(0) Converting physical 0 to logical package 0
[ 0.539596] smpboot: Max logical packages: 19
2. max_cpus=8, should still enumerate all packages:
[ 0.526494] smpboot: APIC(0) Converting physical 0 to logical package 0
[ 0.532428] smpboot: APIC(40) Converting physical 1 to logical package 1
[ 0.538456] smpboot: APIC(80) Converting physical 2 to logical package 2
[ 0.544486] smpboot: APIC(c0) Converting physical 3 to logical package 3
[ 0.550524] smpboot: Max logical packages: 19
3. nr_cpus=49 ( 2 socket + 1 core on 3rd socket), should stop enumerating in
package 2:
[ 0.521378] smpboot: APIC(0) Converting physical 0 to logical package 0
[ 0.527314] smpboot: APIC(40) Converting physical 1 to logical package 1
[ 0.533345] smpboot: APIC(80) Converting physical 2 to logical package 2
[ 0.539368] smpboot: Max logical packages: 19
4. maxcpus=49, should still enumerate all packages:
[ 0.525591] smpboot: APIC(0) Converting physical 0 to logical package 0
[ 0.531525] smpboot: APIC(40) Converting physical 1 to logical package 1
[ 0.537547] smpboot: APIC(80) Converting physical 2 to logical package 2
[ 0.543579] smpboot: APIC(c0) Converting physical 3 to logical package 3
[ 0.549624] smpboot: Max logical packages: 19
5. kdump (nr_cpus=1) works as well.
Reported-by: Frank Ramsay <framsay@redhat.com>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160815101700.GA30090@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Similar to:
efaad554b4 ("x86/microcode/intel: Fix initrd loading with CONFIG_RANDOMIZE_MEMORY=y")
... fix microcode loading from the initrd on AMD by adding the
randomization offset to the microcode patch container within the initrd.
Reported-and-tested-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-tip-commits@vger.kernel.org
Link: http://lkml.kernel.org/r/20160817113314.GA19221@nazgul.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
* pm-sleep:
PM / hibernate: Fix rtree_next_node() to avoid walking off list ends
x86/power/64: Use __pa() for physical address computation
PM / sleep: Update some system sleep documentation
1. fix ctx pointer
Use req_ctx which is the ctx for the next job that have
been completed in the lanes instead of the first
completed job rctx, whose completion could have been
called and released.
Signed-off-by: Xiaodong Liu <xiaodong.liu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
1. fix ctx pointer
Use req_ctx which is the ctx for the next job that have
been completed in the lanes instead of the first
completed job rctx, whose completion could have been
called and released.
2. fix digest copy
Use XMM register to copy another 16 bytes sha256 digest
instead of a regular register.
Signed-off-by: Xiaodong Liu <xiaodong.liu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The value of temp_level4_pgt is the physical address of the
top-level page directory, so use __pa() to compute it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
- Fix the x86 identity mapping creation helpers to avoid the
assumption that the base address of the mapping will always be
aligned at the PGD level, as it may be aligned at the PUD level
if address space randomization is enabled (Rafael Wysocki).
- Fix the hibernation core to avoid executing tracing functions
before restoring the processor state completely during resume
(Thomas Garnier).
- Fix a recently introduced regression in the powernv cpufreq
driver that causes it to crash due to an out-of-bounds array
access (Akshay Adiga).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=DWxX
-----END PGP SIGNATURE-----
Merge tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Two hibernation fixes allowing it to work with the recently added
randomization of the kernel identity mapping base on x86-64 and one
cpufreq driver regression fix.
Specifics:
- Fix the x86 identity mapping creation helpers to avoid the
assumption that the base address of the mapping will always be
aligned at the PGD level, as it may be aligned at the PUD level if
address space randomization is enabled (Rafael Wysocki).
- Fix the hibernation core to avoid executing tracing functions
before restoring the processor state completely during resume
(Thomas Garnier).
- Fix a recently introduced regression in the powernv cpufreq driver
that causes it to crash due to an out-of-bounds array access
(Akshay Adiga)"
* tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / hibernate: Restore processor state before using per-CPU variables
x86/power/64: Always create temporary identity mapping correctly
cpufreq: powernv: Fix crash in gpstate_timer_handler()
Pull x86 fixes from Ingo Molnar:
"This is bigger than usual - the reason is partly a pent-up stream of
fixes after the merge window and partly accidental. The fixes are:
- five patches to fix a boot failure on Andy Lutomirsky's laptop
- four SGI UV platform fixes
- KASAN fix
- warning fix
- documentation update
- swap entry definition fix
- pkeys fix
- irq stats fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe()
x86/efi: Allocate a trampoline if needed in efi_free_boot_services()
x86/boot: Rework reserve_real_mode() to allow multiple tries
x86/boot: Defer setup_real_mode() to early_initcall time
x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly
x86/boot: Run reserve_bios_regions() after we initialize the memory map
x86/irq: Do not substract irq_tlb_count from irq_call_count
x86/mm: Fix swap entry comment and macro
x86/mm/kaslr: Fix -Wformat-security warning
x86/mm/pkeys: Fix compact mode by removing protection keys' XSAVE buffer manipulation
x86/build: Reduce the W=1 warnings noise when compiling x86 syscall tables
x86/platform/UV: Fix kernel panic running RHEL kdump kernel on UV systems
x86/platform/UV: Fix problem with UV4 BIOS providing incorrect PXM values
x86/platform/UV: Fix bug with iounmap() of the UV4 EFI System Table causing a crash
x86/platform/UV: Fix problem with UV4 Socket IDs not being contiguous
x86/entry: Clarify the RF saving/restoring situation with SYSCALL/SYSRET
x86/mm: Disable preemption during CR3 read+write
x86/mm/KASLR: Increase BRK pages for KASLR memory randomization
x86/mm/KASLR: Fix physical memory calculation on KASLR memory randomization
x86, kasan, ftrace: Put APIC interrupt handlers into .irqentry.text
Pull timer fixes from Ingo Molnar:
"Misc fixes: a /dev/rtc regression fix, two APIC timer period
calibration fixes, an ARM clocksource driver fix and a NOHZ
power use regression fix"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hpet: Fix /dev/rtc breakage caused by RTC cleanup
x86/timers/apic: Inform TSC deadline clockevent device about recalibration
x86/timers/apic: Fix imprecise timer interrupts by eliminating TSC clockevents frequency roundoff error
timers: Fix get_next_timer_interrupt() computation
clocksource/arm_arch_timer: Force per-CPU interrupt to be level-triggered
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, plus two uncore-PMU fixes, an uprobes fix, a
perf-cgroups fix and an AUX events fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Add enable_box for client MSR uncore
perf/x86/intel/uncore: Fix uncore num_counters
uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions
perf/core: Set cgroup in CPU contexts for new cgroup events
perf/core: Fix sideband list-iteration vs. event ordering NULL pointer deference crash
perf probe ppc64le: Fix probe location when using DWARF
perf probe: Add function to post process kernel trace events
tools: Sync cpufeatures headers with the kernel
toops: Sync tools/include/uapi/linux/bpf.h with the kernel
tools: Sync cpufeatures.h and vmx.h with the kernel
perf probe: Support signedness casting
perf stat: Avoid skew when reading events
perf probe: Fix module name matching
perf probe: Adjust map->reloc offset when finding kernel symbol from map
perf hists: Trim libtraceevent trace_seq buffers
perf script: Add 'bpf-output' field to usage message
There are bug reports about miscounting uncore counters on some
client machines like Sandybridge, Broadwell and Skylake. It is
very likely to be observed on idle systems.
This issue is caused by a hardware issue. PERF_GLOBAL_CTL could be
cleared after Package C7, and nothing will be count.
The related errata (HSD 158) could be found in:
www.intel.com/content/dam/www/public/us/en/documents/specification-updates/4th-gen-core-family-desktop-specification-update.pdf
This patch tries to work around this issue by re-enabling PERF_GLOBAL_CTL
in ->enable_box(). The workaround does not cover all cases. It helps for new
events after returning from C7. But it cannot prevent C7, it will still
miscount if a counter is already active.
There is no drawback in leaving it enabled, so it does not need
disable_box() here.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/1470925874-59943-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some uncore boxes' num_counters value for Haswell server and
Broadwell server are not correct (too large, off by one).
This issue was found by comparing the code with the document. Although
there is no bug report from users yet, accessing non-existent counters
is dangerous and the behavior is undefined: it may cause miscounting or
even crashes.
This patch makes them consistent with the uncore document.
Reported-by: Lukasz Odzioba <lukasz.odzioba@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1470925820-59847-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since instruction decoder now supports EVEX-encoded instructions, two fixes
are needed to correctly handle them in uprobes.
Extended bits for MODRM.rm field need to be sanitized just like we do it
for VEX3, to avoid encoding wrong register for register-relative access.
EVEX has _two_ extended bits: b and x. Theoretically, EVEX.x should be
ignored by the CPU (since GPRs go only up to 15, not 31), but let's be
paranoid here: proper encoding for register-relative access
should have EVEX.x = 1.
Secondly, we should fetch vex.vvvv for EVEX too.
This is now super easy because instruction decoder populates
vex_prefix.bytes[2] for all flavors of (e)vex encodings, even for VEX2.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # v4.1+
Fixes: 8a764a875f ("x86/asm/decoder: Create artificial 3rd byte for 2-byte VEX")
Link: http://lkml.kernel.org/r/20160811154521.20469-1-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I made a mistake while converting the driver to the hotplug state
machine and as a result x2apic_cluster_probe() was accessing
cpus_in_cluster before allocating it.
This patch fixes it by setting the cpumask after the allocation the
memory succeeded.
While at it, I marked two functions static which are only used within
this file.
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 6b2c28471d ("x86/x2apic: Convert to CPU hotplug state machine")
Link: http://lkml.kernel.org/r/1470924515-9444-1-git-send-email-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This problem has actually been in the UV code for a while, but we didn't
catch it until recently, because we had been relying on EFI_OLD_MEMMAP
to allow our systems to boot for a period of time. We noticed the issue
when trying to kexec a recent community kernel, where we hit this NULL
pointer dereference in efi_sync_low_kernel_mappings():
[ 0.337515] BUG: unable to handle kernel NULL pointer dereference at 0000000000000880
[ 0.346276] IP: [<ffffffff8105df8d>] efi_sync_low_kernel_mappings+0x5d/0x1b0
The problem doesn't show up with EFI_OLD_MEMMAP because we skip the
chunk of setup_efi_state() that sets the efi_loader_signature for the
kexec'd kernel. When the kexec'd kernel boots, it won't set EFI_BOOT in
setup_arch, so we completely avoid the bug.
We always kexec with noefi on the command line, so this shouldn't be an
issue, but since we're not actually checking for efi_runtime_disabled in
uv_bios_init(), we end up trying to do EFI runtime callbacks when we
shouldn't be. This patch just adds a check for efi_runtime_disabled in
uv_bios_init() so that we don't map in uv_systab when runtime_disabled ==
true.
Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: <stable@vger.kernel.org> # v4.7
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1470912120-22831-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On my Dell XPS 13 9350 with firmware 1.4.4 and SGX on, if I boot
Fedora 24's grub2-efi off a hard disk, my first 1MB of RAM looks
like:
efi: mem00: [Runtime Data |RUN| | | | | | | |WB|WT|WC|UC] range=[0x0000000000000000-0x0000000000000fff] (0MB)
efi: mem01: [Boot Data | | | | | | | | |WB|WT|WC|UC] range=[0x0000000000001000-0x0000000000027fff] (0MB)
efi: mem02: [Loader Data | | | | | | | | |WB|WT|WC|UC] range=[0x0000000000028000-0x0000000000029fff] (0MB)
efi: mem03: [Reserved | | | | | | | | |WB|WT|WC|UC] range=[0x000000000002a000-0x000000000002bfff] (0MB)
efi: mem04: [Runtime Data |RUN| | | | | | | |WB|WT|WC|UC] range=[0x000000000002c000-0x000000000002cfff] (0MB)
efi: mem05: [Loader Data | | | | | | | | |WB|WT|WC|UC] range=[0x000000000002d000-0x000000000002dfff] (0MB)
efi: mem06: [Conventional Memory| | | | | | | | |WB|WT|WC|UC] range=[0x000000000002e000-0x0000000000057fff] (0MB)
efi: mem07: [Reserved | | | | | | | | |WB|WT|WC|UC] range=[0x0000000000058000-0x0000000000058fff] (0MB)
efi: mem08: [Conventional Memory| | | | | | | | |WB|WT|WC|UC] range=[0x0000000000059000-0x000000000009ffff] (0MB)
My EBDA is at 0x2c000, which blocks off everything from 0x2c000 and
up, and my trampoline is 0x6000 bytes (6 pages), so it doesn't fit
in the loader data range at 0x28000.
Without this patch, it panics due to a failure to allocate the
trampoline. With this patch, it works:
[ +0.001744] Base memory trampoline at [ffff880000001000] 1000 size 24576
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/998c77b3bf709f3dfed85cb30701ed1a5d8a438b.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If reserve_real_mode() fails, panicing immediately means we're
doomed. Make it safe to try more than once to allocate the
trampoline:
- Degrade a failure from panic() to pr_info(). (If we make it to
setup_real_mode() without reserving the trampoline, we'll panic
them.)
- Factor out helpers so that platform code can supply a specific
address to try.
- Warn if reserve_real_mode() is called after we're done with the
memblock allocator. If that were to happen, we would behave
unpredictably.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/876e383038f3e9971aa72fd20a4f5da05f9d193d.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's no need to run setup_real_mode() as early as we run it.
Defer it to the same early_initcall that sets up the page
permissions for the real mode code.
This should be a code size reduction. More importantly, it give us
a longer window in which we can allocate the real mode trampoline.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fd62f0da4f79357695e9bf3e365623736b05f119.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The initialization process for trampoline_cr4_features and
mmu_cr4_features was confusing. The intent is for mmu_cr4_features
and *trampoline_cr4_features to stay in sync, but
trampoline_cr4_features is NULL until setup_real_mode() runs. The
old code synchronized *trampoline_cr4_features *twice*, once in
setup_real_mode() and once in setup_arch(). It also initialized
mmu_cr4_features in setup_real_mode(), which causes the actual value
of mmu_cr4_features to potentially depend on when setup_real_mode()
is called.
With this patch, mmu_cr4_features is initialized directly in
setup_arch(), and *trampoline_cr4_features is synchronized to
mmu_cr4_features when the trampoline is set up.
After this patch, it should be safe to defer setup_real_mode().
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/d48a263f9912389b957dd495a7127b009259ffe0.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
reserve_bios_regions() is a quirk that reserves memory that we might
otherwise think is available. There's no need to run it so early,
and running it before we have the memory map initialized with its
non-quirky inputs makes it hard to make reserve_bios_regions() more
intelligent.
Move it right after we populate the memblock state.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Matt Fleming <mfleming@suse.de>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/59f58618911005c799c6c9979ce6ae4881d907c2.1470821230.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since commit:
52aec3308d ("x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR")
the TLB remote shootdown is done through call function vector. That
commit didn't take care of irq_tlb_count, which a later commit:
fd0f586972 ("x86: Distinguish TLB shootdown interrupts from other functions call interrupts")
... tried to fix.
The fix assumes every increase of irq_tlb_count has a corresponding
increase of irq_call_count. So the irq_call_count is always bigger than
irq_tlb_count and we could substract irq_tlb_count from irq_call_count.
Unfortunately this is not true for the smp_call_function_single() case.
The IPI is only sent if the target CPU's call_single_queue is empty when
adding a csd into it in generic_exec_single. That means if two threads
are both adding flush tlb csds to the same CPU's call_single_queue, only
one IPI is sent. In other words, the irq_call_count is incremented by 1
but irq_tlb_count is incremented by 2. Over time, irq_tlb_count will be
bigger than irq_call_count and the substract will produce a very large
irq_call_count value due to overflow.
Considering that:
1) it's not worth to send more IPIs for the sake of accurate counting of
irq_call_count in generic_exec_single();
2) it's not easy to tell if the call function interrupt is for TLB
shootdown in __smp_call_function_single_interrupt().
Not to exclude TLB shootdown from call function count seems to be the
simplest fix and this patch just does that.
This bug was found by LKP's cyclic performance regression tracking recently
with the vm-scalability test suite. I have bisected to commit:
3dec0ba0be ("mm/rmap: share the i_mmap_rwsem")
This commit didn't do anything wrong but revealed the irq_call_count
problem. IIUC, the commit makes rwc->remap_one in rmap_walk_file
concurrent with multiple threads. When remap_one is try_to_unmap_one(),
then multiple threads could queue flush TLB to the same CPU but only
one IPI will be sent.
Since the commit was added in Linux v3.19, the counting problem only
shows up from v3.19 onwards.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Cc: Alex Shi <alex.shi@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Link: http://lkml.kernel.org/r/20160811074430.GA18163@aaronlu.sh.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A recent patch changed the format of a swap PTE.
The comment explaining the format of the swap PTE is wrong about
the bits used for the swap type field. Amusingly, the ASCII art
and the patch description are correct, but the comment itself
is wrong.
As I was looking at this, I also noticed that the
SWP_OFFSET_FIRST_BIT has an off-by-one error. This does not
really hurt anything. It just wasted a bit of space in the PTE,
giving us 2^59 bytes of addressable space in our swapfiles
instead of 2^60. But, it doesn't match with the comments, and it
wastes a bit of space, so fix it.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Fixes: 00839ee3b2 ("x86/mm: Move swap offset/type up in PTE to work around erratum")
Link: http://lkml.kernel.org/r/20160810172325.E56AD7DA@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
debug_putstr() is used to output strings without using printf-like
formatting but debug_putstr(v) is defined as early_printk(v) in
arch/x86/lib/kaslr.c.
This makes clang reports the following warning when building
with -Wformat-security:
arch/x86/lib/kaslr.c:57:15: warning: format string is not a string
literal (potentially insecure) [-Wformat-security]
debug_putstr(purpose);
^~~~~~~
Fix this by using "%s" in early_printk().
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160806102039.27221-1-nicolas.iooss_linux@m4x.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Memory Protection Keys "rights register" (PKRU) is
XSAVE-managed, and is saved/restored along with the FPU state.
When kernel code accesses FPU regsisters, it does a delicate
dance with preempt. Otherwise, the context switching code can
get confused as to whether the most up-to-date state is in the
registers themselves or in the XSAVE buffer.
But, PKRU is not a normal FPU register. Using it does not
generate the normal device-not-available (#NM) exceptions which
means we can not manage it lazily, and the kernel completley
disallows using lazy mode when it is enabled.
The dance with preempt *only* occurs when managing the FPU
lazily. Since we never manage PKRU lazily, we do not have to do
the dance with preempt; we can access it directly. Doing it
this way saves a ton of complicated code (and is faster too).
Further, the XSAVES reenabling failed to patch a bit of code
in fpu__xfeature_set_state() the checked for compacted buffers.
That check caused fpu__xfeature_set_state() to silently refuse to
work when the kernel is using compacted XSAVE buffers. This
broke execute-only and future pkey_mprotect() support when using
compact XSAVE buffers.
But, removing fpu__xfeature_set_state() gets rid of this issue,
in addition to the nice cleanup and speedup.
This fixes the same thing as a fix that Sai posted:
https://lkml.org/lkml/2016/7/25/637
The fix that he posted is a much more obviously correct, but I
think we should just do this instead.
Reported-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-Cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20160727232040.7D060DAD@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Building an X86_64 kernel with W=1 throws a total of 9,948 lines of warnings of
this form for both 32-bit and 64-bit syscall tables. Given that the entire rest
of the build for my config only generates 8,375 lines of output, this is a big
reduction in the warnings generated.
The warnings follow this pattern:
./arch/x86/include/generated/asm/syscalls_32.h:885:21: warning: initialized field overwritten [-Woverride-init]
__SYSCALL_I386(379, compat_sys_pwritev2, )
^
arch/x86/entry/syscall_32.c:13:46: note: in definition of macro '__SYSCALL_I386'
#define __SYSCALL_I386(nr, sym, qual) [nr] = sym,
^~~
./arch/x86/include/generated/asm/syscalls_32.h:885:21: note: (near initialization for 'ia32_sys_call_table[379]')
__SYSCALL_I386(379, compat_sys_pwritev2, )
^
arch/x86/entry/syscall_32.c:13:46: note: in definition of macro '__SYSCALL_I386'
#define __SYSCALL_I386(nr, sym, qual) [nr] = sym,
Since we intentionally build the syscall tables this way, ignore that one
warning in the two files.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/7464.1470021890@turing-police.cc.vt.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The latest UV kernel support panics when RHEL7 kexec's the kdump kernel
to make a dumpfile. This patch fixes the problem by turning off all UV
support if NUMA is off.
Tested-by: Frank Ramsay <framsay@sgi.com>
Tested-by: John Estabrook <estabrook@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Reviewed-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160801184050.577755634@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There are some circumstances where the UV4 BIOS cannot provide the
correct Proximity Node values to associate with specific Sockets and
Physical Nodes. The decision was made to remove these values from BIOS
and for the kernel to get these values from the standard ACPI tables.
Tested-by: Frank Ramsay <framsay@sgi.com>
Tested-by: John Estabrook <estabrook@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Reviewed-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160801184050.414210079@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Save the uv_systab::size field before doing the iounmap()
of the struct pointer, to avoid a NULL dereference crash.
Tested-by: Frank Ramsay <framsay@sgi.com>
Tested-by: John Estabrook <estabrook@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Reviewed-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160801184050.250424783@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The UV4 Socket IDs are not guaranteed to equate to Node values which
can cause the GAM (Global Addressable Memory) table lookups to fail.
Fix this by using an independent index into the GAM table instead of
the Socket ID to reference the base address.
Tested-by: Frank Ramsay <framsay@sgi.com>
Tested-by: John Estabrook <estabrook@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Reviewed-by: Nathan Zimmer <nzimmer@sgi.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160801184050.048755337@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's a subtle preemption race on UP kernels:
Usually current->mm (and therefore mm->pgd) stays the same during the
lifetime of a task so it does not matter if a task gets preempted during
the read and write of the CR3.
But then, there is this scenario on x86-UP:
TaskA is in do_exit() and exit_mm() sets current->mm = NULL followed by:
-> mmput()
-> exit_mmap()
-> tlb_finish_mmu()
-> tlb_flush_mmu()
-> tlb_flush_mmu_tlbonly()
-> tlb_flush()
-> flush_tlb_mm_range()
-> __flush_tlb_up()
-> __flush_tlb()
-> __native_flush_tlb()
At this point current->mm is NULL but current->active_mm still points to
the "old" mm.
Let's preempt taskA _after_ native_read_cr3() by taskB. TaskB has its
own mm so CR3 has changed.
Now preempt back to taskA. TaskA has no ->mm set so it borrows taskB's
mm and so CR3 remains unchanged. Once taskA gets active it continues
where it was interrupted and that means it writes its old CR3 value
back. Everything is fine because userland won't need its memory
anymore.
Now the fun part:
Let's preempt taskA one more time and get back to taskB. This
time switch_mm() won't do a thing because oldmm (->active_mm)
is the same as mm (as per context_switch()). So we remain
with a bad CR3 / PGD and return to userland.
The next thing that happens is handle_mm_fault() with an address for
the execution of its code in userland. handle_mm_fault() realizes that
it has a PTE with proper rights so it returns doing nothing. But the
CPU looks at the wrong PGD and insists that something is wrong and
faults again. And again. And one more time…
This pagefault circle continues until the scheduler gets tired of it and
puts another task on the CPU. It gets little difficult if the task is a
RT task with a high priority. The system will either freeze or it gets
fixed by the software watchdog thread which usually runs at RT-max prio.
But waiting for the watchdog will increase the latency of the RT task
which is no good.
Fix this by disabling preemption across the critical code section.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1470404259-26290-1-git-send-email-bigeasy@linutronix.de
[ Prettified the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Default implementation expects 6 pages maximum are needed for low page
allocations. If KASLR memory randomization is enabled, the worse case
of e820 layout would require 12 pages (no large pages). It is due to the
PUD level randomization and the variable e820 memory layout.
This bug was found while doing extensive testing of KASLR memory
randomization on different type of hardware.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Aleksey Makarov <aleksey.makarov@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: kernel-hardening@lists.openwall.com
Fixes: 021182e52f ("Enable KASLR for physical mapping memory regions")
Link: http://lkml.kernel.org/r/1470762665-88032-2-git-send-email-thgarnie@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Initialize KASLR memory randomization after max_pfn is initialized. Also
ensure the size is rounded up. It could create problems on machines
with more than 1Tb of memory on certain random addresses.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Aleksey Makarov <aleksey.makarov@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: kernel-hardening@lists.openwall.com
Fixes: 021182e52f ("Enable KASLR for physical mapping memory regions")
Link: http://lkml.kernel.org/r/1470762665-88032-1-git-send-email-thgarnie@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ville Syrjälä reports "The first time I run hwclock after rebooting
I get this:
open("/dev/rtc", O_RDONLY) = 3
ioctl(3, PHN_SET_REGS or RTC_UIE_ON, 0) = 0
select(4, [3], NULL, NULL, {10, 0}) = 0 (Timeout)
ioctl(3, PHN_NOT_OH or RTC_UIE_OFF, 0) = 0
close(3) = 0
On all subsequent runs I get this:
open("/dev/rtc", O_RDONLY) = 3
ioctl(3, PHN_SET_REGS or RTC_UIE_ON, 0) = -1 EINVAL (Invalid argument)
ioctl(3, RTC_RD_TIME, 0x7ffd76b3ae70) = -1 EINVAL (Invalid argument)
close(3) = 0"
This was caused by a stupid typo in a patch that should have been
a simple rename to move around contents of a header file, but
accidentally wrote zeroes into the rtc rather than reading from
it:
463a86304c ("char/genrtc: x86: remove remnants of asm/rtc.h")
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rtc-linux@googlegroups.com
Fixes: 463a86304c ("char/genrtc: x86: remove remnants of asm/rtc.h")
Link: http://lkml.kernel.org/r/20160809195528.1604312-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>