Accessing the per cpu data via per_cpu(, smp_processor_id()) is
pointless. Use this_cpu_ptr() instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.829552757@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The two NOP5s are noise in the rest of the work which is done by the timer
interrupt and modern CPUs are pretty good in optimizing NOPs anyway.
Get rid of the interrupt handler duplication and move the tracepoints into
the regular handler.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170828064956.751247330@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make use of the new irqvector tracing static key and remove the duplicated
trace_do_pagefault() implementation.
If irq vector tracing is disabled, then the overhead of this is a single
NOP5, which is a reasonable tradeoff to avoid duplicated code and the
unholy macro mess.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.672965407@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Switching the IDT just for avoiding tracepoints creates a completely
impenetrable macro/inline/ifdef mess.
There is no point in avoiding tracepoints for most of the traps/exceptions.
For the more expensive tracepoints, like pagefaults, this can be handled with
an explicit static key.
Preparatory patch to remove the tracing IDT.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.593094539@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
EISA has absolutely nothing to do with traps, so move it out of traps.c
into its own eisa.c file.
Furthermore, the EISA bus detection does not need to run during
very early boot, it's good enough to run it before the EISA bus
and drivers are initialized.
I.e. instead of calling it from the very early trap_init() code,
make it a subsys_initcall().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.515322409@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Also remove the unparseable comment in the other place while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.436711634@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This variable is beyond pointless. Nothing allocates a vector via
alloc_gate() below FIRST_SYSTEM_VECTOR. So nothing can change
first_system_vector.
If there is a need for a gate below FIRST_SYSTEM_VECTOR then it can be
added to the vector defines and FIRST_SYSTEM_VECTOR can be adjusted
accordingly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.357109735@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Last user (lguest) is gone. Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064956.201432430@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Avoid potentially dereferencing a NULL pointer when saving a microcode
patch for early loading on the application processors.
While at it, drop the IS_ERR() checking in favor of simpler, NULL-ptr
checks which are sufficient and rename __alloc_microcode_buf() to
memdup_patch() to more precisely denote what it does.
No functionality change.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825100456.n236w3jebteokfd6@pd.tnic
sme_encrypt_execute() stashes the stack pointer on entry into %rbp
because it allocates a one-page stack in the non-encrypted area for the
encryption routine to use. When the latter is done, it restores it from
%rbp again, before returning.
However, it uses the FRAME_* macros partially but restores %rsp from
%rbp explicitly with a MOV. And this is fine as long as the macros
*actually* do something.
Unless, you do a !CONFIG_FRAME_POINTER build where those macros
are empty. Then, we still restore %rsp from %rbp but %rbp contains
*something* and this leads to a stack corruption. The manifestation
being a triple-fault during early boot when testing SME. Good luck to me
debugging this with the clumsy endless-loop-in-asm method and narrowing
it down gradually. :-(
So, long story short, open-code the frame macros so that there's no
monkey business and we avoid subtly breaking SME depending on the
.config.
Fixes: 6ebcb06071 ("x86/mm: Add support to encrypt the kernel in-place")
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Link: http://lkml.kernel.org/r/20170827163924.25552-1-bp@alien8.de
Pull x86 fixes from Ingo Molnar:
"Two fixes: one for an ldt_struct handling bug and a cherry-picked
objtool fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix use-after-free of ldt_struct
objtool: Fix '-mtune=atom' decoding support in objtool 2.0
The following commit:
d0ec49d4de ("kvm/x86/svm: Support Secure Memory Encryption within KVM")
uses __sme_clr() to remove the C-bit in rsvd_bits(). rsvd_bits() is
just a simple function to return some 1 bits. Applying a mask based
on properties of the host MMU is incorrect. Additionally, the masks
computed by __reset_rsvds_bits_mask also apply to guest page tables,
where the C bit is reserved since we don't emulate SME.
The fix is to clear the C-bit from rsvd_bits_mask array after it has been
populated from __reset_rsvds_bits_mask()
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: kvm@vger.kernel.org
Cc: paolo.bonzini@gmail.com
Fixes: d0ec49d ("kvm/x86/svm: Support Secure Memory Encryption within KVM")
Link: http://lkml.kernel.org/r/20170825205540.123531-1-brijesh.singh@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This follows efi_mem_attributes(), as it's similarly generic. Drop
__weak from that one though (and don't introduce it for efi_mem_type()
in the first place) to make clear that other overrides to these
functions are really not intended.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-5-ard.biesheuvel@linaro.org
[ Resolved conflict with: f99afd08a4: (efi: Update efi_mem_type() to return an error rather than 0) ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a machine is reset while secrets are present in RAM, it may be
possible for code executed after the reboot to extract those secrets
from untouched memory. The Trusted Computing Group specified a mechanism
for requesting that the firmware clear all RAM on reset before booting
another OS. This is done by setting the MemoryOverwriteRequestControl
variable at startup. If userspace can ensure that all secrets are
removed as part of a controlled shutdown, it can reset this variable to
0 before triggering a hardware reboot.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is code duplicated over all architecture's headers for
futex_atomic_op_inuser. Namely op decoding, access_ok check for uaddr,
and comparison of the result.
Remove this duplication and leave up to the arches only the needed
assembly which is now in arch_futex_atomic_op_inuser.
This effectively distributes the Will Deacon's arm64 fix for undefined
behaviour reported by UBSAN to all architectures. The fix was done in
commit 5f16a046f8 (arm64: futex: Fix undefined behaviour with
FUTEX_OP_OPARG_SHIFT usage). Look there for an example dump.
And as suggested by Thomas, check for negative oparg too, because it was
also reported to cause undefined behaviour report.
Note that s390 removed access_ok check in d12a29703 ("s390/uaccess:
remove pointless access_ok() checks") as access_ok there returns true.
We introduce it back to the helper for the sake of simplicity (it gets
optimized away anyway).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390]
Acked-by: Chris Metcalf <cmetcalf@mellanox.com> [for tile]
Reviewed-by: Darren Hart (VMware) <dvhart@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com> [core/arm64]
Cc: linux-mips@linux-mips.org
Cc: Rich Felker <dalias@libc.org>
Cc: linux-ia64@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: peterz@infradead.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sparclinux@vger.kernel.org
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux-s390@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-hexagon@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-xtensa@linux-xtensa.org
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: openrisc@lists.librecores.org
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Stafford Horne <shorne@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Henderson <rth@twiddle.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-parisc@vger.kernel.org
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-alpha@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20170824073105.3901-1-jslaby@suse.cz
Command line options allow us to ignore features that we don't want.
Also we can re-enable options that have been disabled on a platform
(so long as the underlying h/w actually supports the option).
[ tglx: Marked the option array __initdata and the helper function __init ]
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Fenghua" <fenghua.yu@intel.com>
Cc: Ravi V" <ravi.v.shankar@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Andi Kleen" <ak@linux.intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Link: http://lkml.kernel.org/r/0c37b0d4dbc30977a3c1cee08b66420f83662694.1503512900.git.tony.luck@intel.com
According to the SDM, if the "use TPR shadow" VM-execution control is
1, bits 11:0 of the virtual-APIC address must be 0 and the address
should set any bits beyond the processor's physical-address width.
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It can be difficult to figure out for user programs what features
the x86 CPU PMU driver actually supports. Currently it requires
grepping in dmesg, but dmesg is not always available.
This adds a caps directory to /sys/bus/event_source/devices/cpu/,
similar to the caps already used on intel_pt, which can be used to
discover the available capabilities cleanly.
Three capabilities are defined:
- pmu_name: Underlying CPU name known to the driver
- max_precise: Max precise level supported
- branches: Known depth of LBR.
Example:
% grep . /sys/bus/event_source/devices/cpu/caps/*
/sys/bus/event_source/devices/cpu/caps/branches:32
/sys/bus/event_source/devices/cpu/caps/max_precise:3
/sys/bus/event_source/devices/cpu/caps/pmu_name:skylake
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/20170822185201.9261-3-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Only show the Intel format attributes in sysfs when the feature is actually
supported with the current model numbers. This allows programs to probe
what format attributes are available, and give a sensible error message
to users if they are not.
This handles near all cases for intel attributes since Nehalem,
except the (obscure) case when the model number if known, but PEBS
is disabled in PERF_CAPABILITIES.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/20170822185201.9261-2-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Skylake changed the encoding of the PEBS data source field.
Some combinations are not available anymore, but some new cases
e.g. for L4 cache hit are added.
Fix up the conversion table for Skylake, similar as had been done
for Nehalem.
On Skylake server the encoding for L4 actually means persistent
memory. Handle this case too.
To properly describe it in the abstracted perf format I had to add
some new fields. Since a hit can have only one level add a new
field that is an enumeration, not a bit field to describe
the level. It can describe any level. Some numbers are also
used to describe PMEM and LFB.
Also add a new generic remote flag that can be combined with
the generic level to signify a remote cache.
And there is an extension field for the snoop indication to handle
the Forward state.
I didn't add a generic flag for hops because it's not needed
for Skylake.
I changed the existing encodings for older CPUs to also fill in the
new level and remote fields.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: jolsa@kernel.org
Link: http://lkml.kernel.org/r/20170816222156.19953-3-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Minor cleanup: use an explicit x86_pmu flag to handle the
missing Lock / TLB information on Nehalem, instead of always
checking the model number for each PEBS sample.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: jolsa@kernel.org
Link: http://lkml.kernel.org/r/20170816222156.19953-2-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following commit:
39a0526fb3 ("x86/mm: Factor out LDT init from context init")
renamed init_new_context() to init_new_context_ldt() and added a new
init_new_context() which calls init_new_context_ldt(). However, the
error code of init_new_context_ldt() was ignored. Consequently, if a
memory allocation in alloc_ldt_struct() failed during a fork(), the
->context.ldt of the new task remained the same as that of the old task
(due to the memcpy() in dup_mm()). ldt_struct's are not intended to be
shared, so a use-after-free occurred after one task exited.
Fix the bug by making init_new_context() pass through the error code of
init_new_context_ldt().
This bug was found by syzkaller, which encountered the following splat:
BUG: KASAN: use-after-free in free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
Read of size 4 at addr ffff88006d2cb7c8 by task kworker/u9:0/3710
CPU: 1 PID: 3710 Comm: kworker/u9:0 Not tainted 4.13.0-rc4-next-20170811 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:52
print_address_description+0x73/0x250 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report+0x24e/0x340 mm/kasan/report.c:409
__asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
__mmdrop+0xe9/0x530 kernel/fork.c:889
mmdrop include/linux/sched/mm.h:42 [inline]
exec_mmap fs/exec.c:1061 [inline]
flush_old_exec+0x173c/0x1ff0 fs/exec.c:1291
load_elf_binary+0x81f/0x4ba0 fs/binfmt_elf.c:855
search_binary_handler+0x142/0x6b0 fs/exec.c:1652
exec_binprm fs/exec.c:1694 [inline]
do_execveat_common.isra.33+0x1746/0x22e0 fs/exec.c:1816
do_execve+0x31/0x40 fs/exec.c:1860
call_usermodehelper_exec_async+0x457/0x8f0 kernel/umh.c:100
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Allocated by task 3700:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627
kmalloc include/linux/slab.h:493 [inline]
alloc_ldt_struct+0x52/0x140 arch/x86/kernel/ldt.c:67
write_ldt+0x7b7/0xab0 arch/x86/kernel/ldt.c:277
sys_modify_ldt+0x1ef/0x240 arch/x86/kernel/ldt.c:307
entry_SYSCALL_64_fastpath+0x1f/0xbe
Freed by task 3700:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3503 [inline]
kfree+0xca/0x250 mm/slab.c:3820
free_ldt_struct.part.2+0xdd/0x150 arch/x86/kernel/ldt.c:121
free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
__mmdrop+0xe9/0x530 kernel/fork.c:889
mmdrop include/linux/sched/mm.h:42 [inline]
__mmput kernel/fork.c:916 [inline]
mmput+0x541/0x6e0 kernel/fork.c:927
copy_process.part.36+0x22e1/0x4af0 kernel/fork.c:1931
copy_process kernel/fork.c:1546 [inline]
_do_fork+0x1ef/0xfb0 kernel/fork.c:2025
SYSC_clone kernel/fork.c:2135 [inline]
SyS_clone+0x37/0x50 kernel/fork.c:2129
do_syscall_64+0x26c/0x8c0 arch/x86/entry/common.c:287
return_from_SYSCALL_64+0x0/0x7a
Here is a C reproducer:
#include <asm/ldt.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>
static void *fork_thread(void *_arg)
{
fork();
}
int main(void)
{
struct user_desc desc = { .entry_number = 8191 };
syscall(__NR_modify_ldt, 1, &desc, sizeof(desc));
for (;;) {
if (fork() == 0) {
pthread_t t;
srand(getpid());
pthread_create(&t, NULL, fork_thread, NULL);
usleep(rand() % 10000);
syscall(__NR_exit_group, 0);
}
wait(NULL);
}
}
Note: the reproducer takes advantage of the fact that alloc_ldt_struct()
may use vmalloc() to allocate a large ->entries array, and after
commit:
5d17a73a2e ("vmalloc: back off when the current task is killed")
it is possible for userspace to fail a task's vmalloc() by
sending a fatal signal, e.g. via exit_group(). It would be more
difficult to reproduce this bug on kernels without that commit.
This bug only affected kernels with CONFIG_MODIFY_LDT_SYSCALL=y.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> [v4.6+]
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: 39a0526fb3 ("x86/mm: Factor out LDT init from context init")
Link: http://lkml.kernel.org/r/20170824175029.76040-1-ebiggers3@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The host pkru is restored right after vcpu exit (commit 1be0e61), so
KVM_GET_XSAVE will return the host PKRU value instead. Fix this by
using the guest PKRU explicitly in fill_xsave and load_xsave. This
part is based on a patch by Junkang Fu.
The host PKRU data may also not match the value in vcpu->arch.guest_fpu.state,
because it could have been changed by userspace since the last time
it was saved, so skip loading it in kvm_load_guest_fpu.
Reported-by: Junkang Fu <junkang.fjk@alibaba-inc.com>
Cc: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move it to struct kvm_arch_vcpu, replacing guest_pkru_valid with a
simple comparison against the host value of the register. The write of
PKRU in addition can be skipped if the guest has not enabled the feature.
Once we do this, we need not test OSPKE in the host anymore, because
guest_CR4.PKE=1 implies host_CR4.PKE=1.
The static PKU test is kept to elide the code on older CPUs.
Suggested-by: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the host has protection keys disabled, we cannot read and write the
guest PKRU---RDPKRU and WRPKRU fail with #GP(0) if CR4.PKE=0. Block
the PKU cpuid bit in that case.
This ensures that guest_CR4.PKE=1 implies host_CR4.PKE=1.
Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 0a98764567 ("um: Allow building and running on older
hosts") attempted to check for PTRACE_{GET,SET}REGSET under the premise
that these ptrace(2) parameters were directly linked with the presence
of the _xstate structure.
After Richard's commit 61e8d46245 ("um: Correctly check for
PTRACE_GETRESET/SETREGSET") which properly included linux/ptrace.h
instead of asm/ptrace.h, we could get into the original build failure
that I reported:
arch/x86/um/user-offsets.c: In function 'foo':
arch/x86/um/user-offsets.c:54: error: invalid application of 'sizeof' to
incomplete type 'struct _xstate'
On this particular host, we do have PTRACE_GETREGSET and
PTRACE_SETREGSET defined in linux/ptrace.h, but not the structure
_xstate that should be pulled from the following include chain: signal.h
-> bits/sigcontext.h.
Correctly fix this by checking for FP_XSTATE_MAGIC1 which is the correct
way to see if struct _xstate is available or not on the host.
Fixes: 61e8d46245 ("um: Correctly check for PTRACE_GETRESET/SETREGSET")
Fixes: 0a98764567 ("um: Allow building and running on older hosts")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
------------[ cut here ]------------
WARNING: CPU: 7 PID: 3861 at /home/kernel/ssd/kvm/arch/x86/kvm//vmx.c:11299 nested_vmx_vmexit+0x176e/0x1980 [kvm_intel]
CPU: 7 PID: 3861 Comm: qemu-system-x86 Tainted: G W OE 4.13.0-rc4+ #11
RIP: 0010:nested_vmx_vmexit+0x176e/0x1980 [kvm_intel]
Call Trace:
? kvm_multiple_exception+0x149/0x170 [kvm]
? handle_emulation_failure+0x79/0x230 [kvm]
? load_vmcs12_host_state+0xa80/0xa80 [kvm_intel]
? check_chain_key+0x137/0x1e0
? reexecute_instruction.part.168+0x130/0x130 [kvm]
nested_vmx_inject_exception_vmexit+0xb7/0x100 [kvm_intel]
? nested_vmx_inject_exception_vmexit+0xb7/0x100 [kvm_intel]
vmx_queue_exception+0x197/0x300 [kvm_intel]
kvm_arch_vcpu_ioctl_run+0x1b0c/0x2c90 [kvm]
? kvm_arch_vcpu_runnable+0x220/0x220 [kvm]
? preempt_count_sub+0x18/0xc0
? restart_apic_timer+0x17d/0x300 [kvm]
? kvm_lapic_restart_hv_timer+0x37/0x50 [kvm]
? kvm_arch_vcpu_load+0x1d8/0x350 [kvm]
kvm_vcpu_ioctl+0x4e4/0x910 [kvm]
? kvm_vcpu_ioctl+0x4e4/0x910 [kvm]
? kvm_dev_ioctl+0xbe0/0xbe0 [kvm]
The flag "nested_run_pending", which can override the decision of which should run
next, L1 or L2. nested_run_pending=1 means that we *must* run L2 next, not L1. This
is necessary in particular when L1 did a VMLAUNCH of L2 and therefore expects L2 to
be run (and perhaps be injected with an event it specified, etc.). Nested_run_pending
is especially intended to avoid switching to L1 in the injection decision-point.
This can be handled just like the other cases in vmx_check_nested_events, instead of
having a special case in vmx_queue_exception.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
vmx_complete_interrupts() assumes that the exception is always injected,
so it can be dropped by kvm_clear_exception_queue(). However,
an exception cannot be injected immediately if it is: 1) originally
destined to a nested guest; 2) trapped to cause a vmexit; 3) happening
right after VMLAUNCH/VMRESUME, i.e. when nested_run_pending is true.
This patch applies to exceptions the same algorithm that is used for
NMIs, replacing exception.reinject with "exception.injected" (equivalent
to nmi_injected).
exception.pending now represents an exception that is queued and whose
side effects (e.g., update RFLAGS.RF or DR7) have not been applied yet.
If exception.pending is true, the exception might result in a nested
vmexit instead, too (in which case the side effects must not be applied).
exception.injected instead represents an exception that is going to be
injected into the guest at the next vmentry.
Reported-by: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use kvm_event_needs_reinjection() encapsulation.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
update_permission_bitmask currently does a 128-iteration loop to,
essentially, compute a constant array. Computing the 8 bits in parallel
reduces it to 16 iterations, and is enough to speed it up substantially
because many boolean operations in the inner loop become constants or
simplify noticeably.
Because update_permission_bitmask is actually the top item in the profile
for nested vmexits, this speeds up an L2->L1 vmexit by about ten thousand
clock cycles, or up to 30%:
before after
cpuid 35173 25954
vmcall 35122 27079
inl_from_pmtimer 52635 42675
inl_from_qemu 53604 44599
inl_from_kernel 38498 30798
outl_to_kernel 34508 28816
wr_tsc_adjust_msr 34185 26818
rd_tsc_adjust_msr 37409 27049
mmio-no-eventfd:pci-mem 50563 45276
mmio-wildcard-eventfd:pci-mem 34495 30823
mmio-datamatch-eventfd:pci-mem 35612 31071
portio-no-eventfd:pci-io 44925 40661
portio-wildcard-eventfd:pci-io 29708 27269
portio-datamatch-eventfd:pci-io 31135 27164
(I wrote a small C program to compare the tables for all values of CR0.WP,
CR4.SMAP and CR4.SMEP, and they match).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch exposes 5 level page table feature to the VM.
At the same time, the canonical virtual address checking is
extended to support both 48-bits and 57-bits address width.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Extends the shadow paging code, so that 5 level shadow page
table can be constructed if VM is running in 5 level paging
mode.
Also extends the ept code, so that 5 level ept table can be
constructed if maxphysaddr of VM exceeds 48 bits. Unlike the
shadow logic, KVM should still use 4 level ept table for a VM
whose physical address width is less than 48 bits, even when
the VM is running in 5 level paging mode.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
[Unconditionally reset the MMU context in kvm_cpuid_update.
Changing MAXPHYADDR invalidates the reserved bit bitmasks.
- Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now we have 4 level page table and 5 level page table in 64 bits
long mode, let's rename the PT64_ROOT_LEVEL to PT64_ROOT_4LEVEL,
then we can use PT64_ROOT_5LEVEL for 5 level page table, it's
helpful to make the code more clear.
Also PT64_ROOT_MAX_LEVEL is defined as 4, so that we can just
redefine it to 5 whenever a replacement is needed for 5 level
paging.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, KVM uses CR3_L_MODE_RESERVED_BITS to check the
reserved bits in CR3. Yet the length of reserved bits in
guest CR3 should be based on the physical address width
exposed to the VM. This patch changes CR3 check logic to
calculate the reserved bits at runtime.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Return false in kvm_cpuid() when it fails to find the cpuid
entry. Also, this routine(and its caller) is optimized with
a new argument - check_limit, so that the check_cpuid_limit()
fall back can be avoided.
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A guest may not be configured to support XSAVES/XRSTORS, even when the host
does. If the guest does not support XSAVES/XRSTORS, clear the secondary
execution control so that the processor will raise #UD.
Also clear the "allowed-1" bit for XSAVES/XRSTORS exiting in the
IA32_VMX_PROCBASED_CTLS2 MSR, and pass through VMCS12's control in
the VMCS02.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A guest may not be configured to support RDSEED, even when the host
does. If the guest does not support RDSEED, intercept the instruction
and synthesize #UD. Also clear the "allowed-1" bit for RDSEED exiting
in the IA32_VMX_PROCBASED_CTLS2 MSR.
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A guest may not be configured to support RDRAND, even when the host
does. If the guest does not support RDRAND, intercept the instruction
and synthesize #UD. Also clear the "allowed-1" bit for RDRAND exiting
in the IA32_VMX_PROCBASED_CTLS2 MSR.
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, secondary execution controls are divided in three groups:
- static, depending mostly on the module arguments or the processor
(vmx_secondary_exec_control)
- static, depending on CPUID (vmx_cpuid_update)
- dynamic, depending on nested VMX or local APIC state
Because walking CPUID is expensive, prepare_vmcs02 is using only
the first group. This however is unnecessarily complicated. Just
cache the static secondary execution controls, and then prepare_vmcs02
does not need to compute them every time. Computation of all static
secondary execution controls is now kept in a single function,
vmx_compute_secondary_exec_control.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Lguest seems to be rather unused these days. It has seen only patches
ensuring it still builds the last two years and its official state is
"Odd Fixes".
Remove it in order to be able to clean up the paravirt code.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: boris.ostrovsky@oracle.com
Cc: lguest@lists.ozlabs.org
Cc: rusty@rustcorp.com.au
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Xen's paravirt patch function xen_patch() does some special casing for
irq_ops functions to apply relocations when those functions can be
patched inline instead of calls.
Unfortunately none of the special case function replacements is small
enough to be patched inline, so the special case never applies.
As xen_patch() will call paravirt_patch_default() in all cases it can
be just dropped. xen-asm.h doesn't seem necessary without xen_patch()
as the only thing left in it would be the definition of XEN_EFLAGS_NMI
used only once. So move that definition and remove xen-asm.h.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: 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: boris.ostrovsky@oracle.com
Cc: lguest@lists.ozlabs.org
Cc: rusty@rustcorp.com.au
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20170816173157.8633-2-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Enable the Virtual GIF feature. This is done by setting bit 25 at position
60h in the vmcb.
With this feature enabled, the processor uses bit 9 at position 60h as the
virtual GIF when executing STGI/CLGI instructions.
Since the execution of STGI by the L1 hypervisor does not cause a return to
the outermost (L0) hypervisor, the enable_irq_window and enable_nmi_window
are modified.
The IRQ window will be opened even if GIF is not set, under the assumption
that on resuming the L1 hypervisor the IRQ will be held pending until the
processor executes the STGI instruction.
For the NMI window, the STGI intercept is set. This will assist in opening
the window only when GIF=1.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a new cpufeature definition for Virtual GIF.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When enabling interrupt remap, IOAPIC's RTE contains the interrupt_index
field of IRTE. This field is composed of the ->index and the ->index2 members
of 'struct IR_IO_APIC_route_entry' - but what we print out currently only
uses ->index.
Fix it.
Signed-off-by: Raymond Pang <raymondpangxd@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: joro@8bytes.org
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/CAHG4imNDzpDyOVi7MByVrLQ%3DQFuOVqpzJ5F-Xs5z6OZphubj-Q@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Align them vertically for better readability and use BIT_ULL() macro.
No functionality change.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Link: http://lkml.kernel.org/r/20170821080651.4527-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the following commit:
8f91869766 ("x86/build: Fix stack alignment for CLang")
cc-option is only used to determine the name of the stack alignment option
supported by the compiler, but not to verify that the actual parameter
<option>=N is valid in combination with the other CFLAGS.
This causes problems (as reported by the kbuild robot) with older GCC versions
which only support stack alignment on a boundary of 16 bytes or higher.
Also use (__)cc_option to add the stack alignment option to CFLAGS to
make sure only valid options are added.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bernhard.Rosenkranzer@linaro.org
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michael Davidson <md@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hines <srhines@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dianders@chromium.org
Fixes: 8f91869766 ("x86/build: Fix stack alignment for CLang")
Link: http://lkml.kernel.org/r/20170817182047.176752-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Thomas Gleixner:
"Another pile of small fixes and updates for x86:
- Plug a hole in the SMAP implementation which misses to clear AC on
NMI entry
- Fix the norandmaps/ADDR_NO_RANDOMIZE logic so the command line
parameter works correctly again
- Use the proper accessor in the startup64 code for next_early_pgt to
prevent accessing of invalid addresses and faulting in the early
boot code.
- Prevent CPU hotplug lock recursion in the MTRR code
- Unbreak CPU0 hotplugging
- Rename overly long CPUID bits which got introduced in this cycle
- Two commits which mark data 'const' and restrict the scope of data
and functions to file scope by making them 'static'"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Constify attribute_group structures
x86/boot/64/clang: Use fixup_pointer() to access 'next_early_pgt'
x86/elf: Remove the unnecessary ADDR_NO_RANDOMIZE checks
x86: Fix norandmaps/ADDR_NO_RANDOMIZE
x86/mtrr: Prevent CPU hotplug lock recursion
x86: Mark various structures and functions as 'static'
x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized VMSAVE/VMLOAD" CPUID flag
x86/smpboot: Unbreak CPU0 hotplug
x86/asm/64: Clear AC on NMI entries
Pull perf fixes from Thomas Gleixner:
"Two fixes for the perf subsystem:
- Fix an inconsistency of RDPMC mm struct tagging across exec() which
causes RDPMC to fault.
- Correct the timestamp mechanics across IOC_DISABLE/ENABLE which
causes incorrect timestamps and total time calculations"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix time on IOC_ENABLE
perf/x86: Fix RDPMC vs. mm_struct tracking
Pull watchdog fix from Thomas Gleixner:
"A fix for the hardlockup watchdog to prevent false positives with
extreme Turbo-Modes which make the perf/NMI watchdog fire faster than
the hrtimer which is used to verify.
Slightly larger than the minimal fix, which just would increase the
hrtimer frequency, but comes with extra overhead of more watchdog
timer interrupts and thread wakeups for all users.
With this change we restrict the overhead to the extreme Turbo-Mode
systems"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
kernel/watchdog: Prevent false positives with turbo modes
Moving the x86_64 and arm64 PIE base from 0x555555554000 to 0x000100000000
broke AddressSanitizer. This is a partial revert of:
eab09532d4 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
02445990a9 ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB")
The AddressSanitizer tool has hard-coded expectations about where
executable mappings are loaded.
The motivation for changing the PIE base in the above commits was to
avoid the Stack-Clash CVEs that allowed executable mappings to get too
close to heap and stack. This was mainly a problem on 32-bit, but the
64-bit bases were moved too, in an effort to proactively protect those
systems (proofs of concept do exist that show 64-bit collisions, but
other recent changes to fix stack accounting and setuid behaviors will
minimize the impact).
The new 32-bit PIE base is fine for ASan (since it matches the ET_EXEC
base), so only the 64-bit PIE base needs to be reverted to let x86 and
arm64 ASan binaries run again. Future changes to the 64-bit PIE base on
these architectures can be made optional once a more dynamic method for
dealing with AddressSanitizer is found. (e.g. always loading PIE into
the mmap region for marked binaries.)
Link: http://lkml.kernel.org/r/20170807201542.GA21271@beast
Fixes: eab09532d4 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
Fixes: 02445990a9 ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Kostya Serebryany <kcc@google.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 05a4a95279 ("kernel/watchdog: split up config options") lost
the perf-based hardlockup detector's dependency on PERF_EVENTS, which
can result in broken builds with some powerpc configurations.
Restore the dependency. Add it in for x86 too, despite x86 always
selecting PERF_EVENTS it seems reasonable to make the dependency
explicit.
Link: http://lkml.kernel.org/r/20170810114452.6673-1-npiggin@gmail.com
Fixes: 05a4a95279 ("kernel/watchdog: split up config options")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We already always set that type but don't check if it is supported. Also
for nVMX, we only support WB for now. Let's just require it.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Don't use shifts, tag them correctly as EPTP and use better matching
names (PWL vs. GAW).
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
There is currently some confusion between nested and L1 GPAs. The
assignment to "direct" in kvm_mmu_page_fault tries to fix that, but
it is not enough. What this patch does is fence off the MMIO cache
completely when using shadow nested page tables, since we have neither
a GVA nor an L1 GPA to put in the cache. This also allows some
simplifications in kvm_mmu_page_fault and FNAME(page_fault).
The EPT misconfig likewise does not have an L1 GPA to pass to
kvm_io_bus_write, so that must be skipped for guest mode.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Changed comment to say "GPAs" instead of "L1's physical addresses", as
per David's review. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
When a guest causes a page fault which requires emulation, the
vcpu->arch.gpa_available flag is set to indicate that cr2 contains a
valid GPA.
Currently, emulator_read_write_onepage() makes use of gpa_available flag
to avoid a guest page walk for a known MMIO regions. Lets not limit
the gpa_available optimization to just MMIO region. The patch extends
the check to avoid page walk whenever gpa_available flag is set.
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
[Fix EPT=0 according to Wanpeng Li's fix, plus ensure VMX also uses the
new code. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Moved "ret < 0" to the else brach, as per David's review. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Calling handle_mmio_page_fault() has been unnecessary since commit
e9ee956e31 ("KVM: x86: MMU: Move handle_mmio_page_fault() call to
kvm_mmu_page_fault()", 2016-02-22).
handle_mmio_page_fault() can now be made static.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The hardlockup detector on x86 uses a performance counter based on unhalted
CPU cycles and a periodic hrtimer. The hrtimer period is about 2/5 of the
performance counter period, so the hrtimer should fire 2-3 times before the
performance counter NMI fires. The NMI code checks whether the hrtimer
fired since the last invocation. If not, it assumess a hard lockup.
The calculation of those periods is based on the nominal CPU
frequency. Turbo modes increase the CPU clock frequency and therefore
shorten the period of the perf/NMI watchdog. With extreme Turbo-modes (3x
nominal frequency) the perf/NMI period is shorter than the hrtimer period
which leads to false positives.
A simple fix would be to shorten the hrtimer period, but that comes with
the side effect of more frequent hrtimer and softlockup thread wakeups,
which is not desired.
Implement a low pass filter, which checks the perf/NMI period against
kernel time. If the perf/NMI fires before 4/5 of the watchdog period has
elapsed then the event is ignored and postponed to the next perf/NMI.
That solves the problem and avoids the overhead of shorter hrtimer periods
and more frequent softlockup thread wakeups.
Fixes: 58687acba5 ("lockup_detector: Combine nmi_watchdog and softlockup detector")
Reported-and-tested-by: Kan Liang <Kan.liang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: dzickus@redhat.com
Cc: prarit@redhat.com
Cc: ak@linux.intel.com
Cc: babu.moger@oracle.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: acme@redhat.com
Cc: stable@vger.kernel.org
Cc: atomlin@redhat.com
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1708150931310.1886@nanos
- Disable interrupts around reading IA32_APERF and IA32_MPERF in
aperfmperf_snapshot_khz() (introduced recently) to avoid excessive
delays between the reads that may result from interrupt handling
(Doug Smythies).
- Fix the comutation of the CPU frequency to be reported through the
pstate_sample tracepoint in intel_pstate (Doug Smythies).
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Merge tag 'pm-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix two issues related to exposing the current CPU frequency to
user space on x86.
Specifics:
- Disable interrupts around reading IA32_APERF and IA32_MPERF in
aperfmperf_snapshot_khz() (introduced recently) to avoid excessive
delays between the reads that may result from interrupt handling
(Doug Smythies).
- Fix the computation of the CPU frequency to be reported through the
pstate_sample tracepoint in intel_pstate (Doug Smythies)"
* tag 'pm-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: x86: Disable interrupts during MSRs reading
cpufreq: intel_pstate: report correct CPU frequencies during trace
Currently KASLR will parse all e820 entries of RAM type and add all
candidate positions into the slots array. After that we choose one slot
randomly as the new position which the kernel will be decompressed into
and run at.
On systems with EFI enabled, e820 memory regions are coming from EFI
memory regions by combining adjacent regions.
These EFI memory regions have various attributes, and the "mirrored"
attribute is one of them. The physical memory region whose descriptors
in EFI memory map has EFI_MEMORY_MORE_RELIABLE attribute (bit: 16) are
mirrored. The address range mirroring feature of the kernel arranges such
mirrored regions into normal zones and other regions into movable zones.
With the mirroring feature enabled, the code and data of the kernel can only
be located in the more reliable mirrored regions. However, the current KASLR
code doesn't check EFI memory entries, and could choose a new kernel position
in non-mirrored regions. This will break the intended functionality of the
address range mirroring feature.
To fix this, if EFI is detected, iterate EFI memory map and pick the mirrored
region to process for adding candidate of randomization slot. If EFI is disabled
or no mirrored region found, still process the e820 memory map.
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: n-horiguchi@ah.jp.nec.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1502722464-20614-3-git-send-email-bhe@redhat.com
[ Rewrote most of the text. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The existing map iteration helper for_each_efi_memory_desc_in_map can
only be used after the kernel initializes the EFI subsystem to set up
struct efi_memory_map.
Before that we also need iterate map descriptors which are stored in several
intermediate structures, like struct efi_boot_memmap for arch independent
usage and struct efi_info for x86 arch only.
Introduce efi_early_memdesc_ptr() to get pointer to a map descriptor, and
replace several places where that primitive is open coded.
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Various improvements to the text. ]
Acked-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: linux-efi@vger.kernel.org
Cc: n-horiguchi@ah.jp.nec.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/20170816134651.GF21273@x1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This implements refcount_t overflow protection on x86 without a noticeable
performance impact, though without the fuller checking of REFCOUNT_FULL.
This is done by duplicating the existing atomic_t refcount implementation
but with normally a single instruction added to detect if the refcount
has gone negative (e.g. wrapped past INT_MAX or below zero). When detected,
the handler saturates the refcount_t to INT_MIN / 2. With this overflow
protection, the erroneous reference release that would follow a wrap back
to zero is blocked from happening, avoiding the class of refcount-overflow
use-after-free vulnerabilities entirely.
Only the overflow case of refcounting can be perfectly protected, since
it can be detected and stopped before the reference is freed and left to
be abused by an attacker. There isn't a way to block early decrements,
and while REFCOUNT_FULL stops increment-from-zero cases (which would
be the state _after_ an early decrement and stops potential double-free
conditions), this fast implementation does not, since it would require
the more expensive cmpxchg loops. Since the overflow case is much more
common (e.g. missing a "put" during an error path), this protection
provides real-world protection. For example, the two public refcount
overflow use-after-free exploits published in 2016 would have been
rendered unexploitable:
http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/http://cyseclabs.com/page?n=02012016
This implementation does, however, notice an unchecked decrement to zero
(i.e. caller used refcount_dec() instead of refcount_dec_and_test() and it
resulted in a zero). Decrements under zero are noticed (since they will
have resulted in a negative value), though this only indicates that a
use-after-free may have already happened. Such notifications are likely
avoidable by an attacker that has already exploited a use-after-free
vulnerability, but it's better to have them reported than allow such
conditions to remain universally silent.
On first overflow detection, the refcount value is reset to INT_MIN / 2
(which serves as a saturation value) and a report and stack trace are
produced. When operations detect only negative value results (such as
changing an already saturated value), saturation still happens but no
notification is performed (since the value was already saturated).
On the matter of races, since the entire range beyond INT_MAX but before
0 is negative, every operation at INT_MIN / 2 will trap, leaving no
overflow-only race condition.
As for performance, this implementation adds a single "js" instruction
to the regular execution flow of a copy of the standard atomic_t refcount
operations. (The non-"and_test" refcount_dec() function, which is uncommon
in regular refcount design patterns, has an additional "jz" instruction
to detect reaching exactly zero.) Since this is a forward jump, it is by
default the non-predicted path, which will be reinforced by dynamic branch
prediction. The result is this protection having virtually no measurable
change in performance over standard atomic_t operations. The error path,
located in .text.unlikely, saves the refcount location and then uses UD0
to fire a refcount exception handler, which resets the refcount, handles
reporting, and returns to regular execution. This keeps the changes to
.text size minimal, avoiding return jumps and open-coded calls to the
error reporting routine.
Example assembly comparison:
refcount_inc() before:
.text:
ffffffff81546149: f0 ff 45 f4 lock incl -0xc(%rbp)
refcount_inc() after:
.text:
ffffffff81546149: f0 ff 45 f4 lock incl -0xc(%rbp)
ffffffff8154614d: 0f 88 80 d5 17 00 js ffffffff816c36d3
...
.text.unlikely:
ffffffff816c36d3: 48 8d 4d f4 lea -0xc(%rbp),%rcx
ffffffff816c36d7: 0f ff (bad)
These are the cycle counts comparing a loop of refcount_inc() from 1
to INT_MAX and back down to 0 (via refcount_dec_and_test()), between
unprotected refcount_t (atomic_t), fully protected REFCOUNT_FULL
(refcount_t-full), and this overflow-protected refcount (refcount_t-fast):
2147483646 refcount_inc()s and 2147483647 refcount_dec_and_test()s:
cycles protections
atomic_t 82249267387 none
refcount_t-fast 82211446892 overflow, untested dec-to-zero
refcount_t-full 144814735193 overflow, untested dec-to-zero, inc-from-zero
This code is a modified version of the x86 PAX_REFCOUNT atomic_t
overflow defense from the last public patch of PaX/grsecurity, based
on my understanding of the code. Changes or omissions from the original
code are mine and don't reflect the original grsecurity/PaX code. Thanks
to PaX Team for various suggestions for improvement for repurposing this
code to be a refcount-only protection.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Jann Horn <jannh@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Serge E. Hallyn <serge@hallyn.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arozansk@redhat.com
Cc: axboe@kernel.dk
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170815161924.GA133115@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Speculative processor accesses may reference any memory that has a
valid page table entry. While a speculative access won't generate
a machine check, it will log the error in a machine check bank. That
could cause escalation of a subsequent error since the overflow bit
will be then set in the machine check bank status register.
Code has to be double-plus-tricky to avoid mentioning the 1:1 virtual
address of the page we want to map out otherwise we may trigger the
very problem we are trying to avoid. We use a non-canonical address
that passes through the usual Linux table walking code to get to the
same "pte".
Thanks to Dave Hansen for reviewing several iterations of this.
Also see:
http://marc.info/?l=linux-mm&m=149860136413338&w=2
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Elliott, Robert (Persistent Memory) <elliott@hpe.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
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/20170816171803.28342-1-tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
d77698df39 ("x86/build: Specify stack alignment for clang")
intended to use the same stack alignment for clang as with gcc.
The two compilers use different options to configure the stack alignment
(gcc: -mpreferred-stack-boundary=n, clang: -mstack-alignment=n).
The above commit assumes that the clang option uses the same parameter
type as gcc, i.e. that the alignment is specified as 2^n. However clang
interprets the value of this option literally to use an alignment of n,
in consequence the stack remains misaligned.
Change the values used with -mstack-alignment to be the actual alignment
instead of a power of two.
cc-option isn't used here with the typical pattern of KBUILD_CFLAGS +=
$(call cc-option ...). The reason is that older gcc versions don't
support the -mpreferred-stack-boundary option, since cc-option doesn't
verify whether the alternative option is valid it would incorrectly
select the clang option -mstack-alignment..
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bernhard.Rosenkranzer@linaro.org
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michael Davidson <md@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hines <srhines@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dianders@chromium.org
Link: http://lkml.kernel.org/r/20170817004740.170588-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
__startup_64() is normally using fixup_pointer() to access globals in a
position-independent fashion. However 'next_early_pgt' was accessed
directly, which wasn't guaranteed to work.
Luckily GCC was generating a R_X86_64_PC32 PC-relative relocation for
'next_early_pgt', but Clang emitted a R_X86_64_32S, which led to
accessing invalid memory and rebooting the kernel.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Davidson <md@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: c88d71508e ("x86/boot/64: Rewrite startup_64() in C")
Link: http://lkml.kernel.org/r/20170816190808.131748-1-glider@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
register_nmi_handler() can be called from PREEMPT_RT atomic context
(e.g. wakeup_cpu_via_init_nmi() or native_stop_other_cpus()), and thus
ordinary spinlocks cannot be used.
Signed-off-by: Scott Wood <swood@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/20170724213242.27598-1-swood@redhat.com
The ADDR_NO_RANDOMIZE checks in stack_maxrandom_size() and
randomize_stack_top() are not required.
PF_RANDOMIZE is set by load_elf_binary() only if ADDR_NO_RANDOMIZE is not
set, no need to re-check after that.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: http://lkml.kernel.org/r/20170815154011.GB1076@redhat.com
Documentation/admin-guide/kernel-parameters.txt says:
norandmaps Don't use address space randomization. Equivalent
to echo 0 > /proc/sys/kernel/randomize_va_space
but it doesn't work because arch_rnd() which is used to randomize
mm->mmap_base returns a random value unconditionally. And as Kirill
pointed out, ADDR_NO_RANDOMIZE is broken by the same reason.
Just shift the PF_RANDOMIZE check from arch_mmap_rnd() to arch_rnd().
Fixes: 1b028f784e ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20170815153952.GA1076@redhat.com
The use of the ternary operator is redundant as ret can never be
non-zero at that point. Instead, just return nbytes.
Detected by CoverityScan, CID#1452658 ("Logically dead code")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20170808092859.13021-1-colin.king@canonical.com
During a mkdir, the entire limbo list is synchronously checked on each
package for free RMIDs by sending IPIs. With a large number of RMIDs (SKL
has 192) this creates a intolerable amount of work in IPIs.
Replace the IPI based checking of the limbo list with asynchronous worker
threads on each package which periodically scan the limbo list and move the
RMIDs that have:
llc_occupancy < threshold_occupancy
on all packages to the free list.
mkdir now returns -ENOSPC if the free list and the limbo list ere empty or
returns -EBUSY if there are RMIDs on the limbo list and the free list is
empty.
Getting rid of the IPIs also simplifies the data structures and the
serialization required for handling the lists.
[ tglx: Rewrote changelog ... ]
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Link: http://lkml.kernel.org/r/1502845243-20454-3-git-send-email-vikas.shivappa@linux.intel.com
Larry reported a CPU hotplug lock recursion in the MTRR code.
============================================
WARNING: possible recursive locking detected
systemd-udevd/153 is trying to acquire lock:
(cpu_hotplug_lock.rw_sem){.+.+.+}, at: [<c030fc26>] stop_machine+0x16/0x30
but task is already holding lock:
(cpu_hotplug_lock.rw_sem){.+.+.+}, at: [<c0234353>] mtrr_add_page+0x83/0x470
....
cpus_read_lock+0x48/0x90
stop_machine+0x16/0x30
mtrr_add_page+0x18b/0x470
mtrr_add+0x3e/0x70
mtrr_add_page() holds the hotplug rwsem already and calls stop_machine()
which acquires it again.
Call stop_machine_cpuslocked() instead.
Reported-and-tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1708140920250.1865@nanos
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@suse.de>
When I cleaned up the Xen SYSCALL entries, I inadvertently changed
the reported segment registers. Before my patch, regs->ss was
__USER(32)_DS and regs->cs was __USER(32)_CS. After the patch, they
are FLAT_USER_CS/DS(32).
This had a couple unfortunate effects. It confused the
opportunistic fast return logic. It also significantly increased
the risk of triggering a nasty glibc bug:
https://sourceware.org/bugzilla/show_bug.cgi?id=21269
Update the Xen entry code to change it back.
Reported-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Fixes: 8a9949bc71 ("x86/xen/64: Rearrange the SYSCALL entries")
Link: http://lkml.kernel.org/r/daba8351ea2764bb30272296ab9ce08a81bd8264.1502775273.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Backmerge tag 'v4.13-rc5' into drm-next
Linux 4.13-rc5
There's a really nasty nouveau collision, hopefully someone can take a look
once I pushed this out.
Pull crypto fixes from Herbert Xu:
"Fix an error path bug in ixp4xx as well as a read overrun in
sha1-avx2"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: x86/sha1 - Fix reads beyond the number of blocks passed
crypto: ixp4xx - Fix error handling path in 'aead_perform()'
include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
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Merge tag 'for-linus-4.13b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"Some fixes for Xen:
- a fix for a regression introduced in 4.13 for a Xen HVM-guest
configured with KASLR
- a fix for a possible deadlock in the xenbus driver when booting the
system
- a fix for lost interrupts in Xen guests"
* tag 'for-linus-4.13b-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/events: Fix interrupt lost during irq_disable and irq_enable
xen: avoid deadlock in xenbus
xen: fix hvm guest with kaslr enabled
xen: split up xen_hvm_init_shared_info()
x86: provide an init_mem_mapping hypervisor hook
Host-initiated writes to the IA32_APIC_BASE MSR do not have to follow
local APIC state transition constraints, but the value written must be
valid.
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Bailing out immediately if there is no available mmu page to alloc.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
watchdog: BUG: soft lockup - CPU#5 stuck for 22s! [warn_test:3089]
irq event stamp: 20532
hardirqs last enabled at (20531): [<ffffffff8e9b6908>] restore_regs_and_iret+0x0/0x1d
hardirqs last disabled at (20532): [<ffffffff8e9b7ae8>] apic_timer_interrupt+0x98/0xb0
softirqs last enabled at (8266): [<ffffffff8e9badc6>] __do_softirq+0x206/0x4c1
softirqs last disabled at (8253): [<ffffffff8e083918>] irq_exit+0xf8/0x100
CPU: 5 PID: 3089 Comm: warn_test Tainted: G OE 4.13.0-rc3+ #8
RIP: 0010:kvm_mmu_prepare_zap_page+0x72/0x4b0 [kvm]
Call Trace:
make_mmu_pages_available.isra.120+0x71/0xc0 [kvm]
kvm_mmu_load+0x1cf/0x410 [kvm]
kvm_arch_vcpu_ioctl_run+0x1316/0x1bf0 [kvm]
kvm_vcpu_ioctl+0x340/0x700 [kvm]
? kvm_vcpu_ioctl+0x340/0x700 [kvm]
? __fget+0xfc/0x210
do_vfs_ioctl+0xa4/0x6a0
? __fget+0x11d/0x210
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x23/0xc2
? __this_cpu_preempt_check+0x13/0x20
This can be reproduced readily by ept=N and running syzkaller tests since
many syzkaller testcases don't setup any memory regions. However, if ept=Y
rmode identity map will be created, then kvm_mmu_calculate_mmu_pages() will
extend the number of VM's mmu pages to at least KVM_MIN_ALLOC_MMU_PAGES
which just hide the issue.
I saw the scenario kvm->arch.n_max_mmu_pages == 0 && kvm->arch.n_used_mmu_pages == 1,
so there is one active mmu page on the list, kvm_mmu_prepare_zap_page() fails
to zap any pages, however prepare_zap_oldest_mmu_page() always returns true.
It incurs infinite loop in make_mmu_pages_available() which causes mmu->lock
softlockup.
This patch fixes it by setting the return value of prepare_zap_oldest_mmu_page()
according to whether or not there is mmu page zapped.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let's reuse the function introduced with eptp switching.
We don't explicitly have to check against enable_ept_ad_bits, as this
is implicitly done when checking against nested_vmx_ept_caps in
valid_ept_address().
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A Xen HVM guest running with KASLR enabled will die rather soon today
because the shared info page mapping is using va() too early. This was
introduced by commit a5d5f328b0 ("xen:
allocate page for shared info page from low memory").
In order to fix this use early_memremap() to get a temporary virtual
address for shared info until va() can be used safely.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Instead of calling xen_hvm_init_shared_info() on boot and resume split
it up into a boot time function searching for the pfn to use and a
mapping function doing the hypervisor mapping call.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Provide a hook in hypervisor_x86 called after setting up initial
memory mapping.
This is needed e.g. by Xen HVM guests to map the hypervisor shared
info page.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
The newly introduced function is only used when CONFIG_SMP is set:
arch/x86/kernel/cpu/amd.c:305:13: warning: 'legacy_fixup_core_id' defined but not used
This moves the existing #ifdef around the caller so it covers
legacy_fixup_core_id() as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Emanuel Czirai <icanrealizeum@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Fixes: b89b41d0b8 ("x86/cpu/amd: Limit cpu_core_id fixup to families older than F17h")
Link: http://lkml.kernel.org/r/20170811111937.2006128-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Mark a couple of structures and functions as 'static', pointed out by Sparse:
warning: symbol 'bts_pmu' was not declared. Should it be static?
warning: symbol 'p4_event_aliases' was not declared. Should it be static?
warning: symbol 'rapl_attr_groups' was not declared. Should it be static?
symbol 'process_uv2_message' was not declared. Should it be static?
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Andrew Banman <abanman@hpe.com> # for the UV change
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20170810155709.7094-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
"virtual_vmload_vmsave" is what is going to land in /proc/cpuinfo now
as per v4.13-rc4, for a single feature bit which is clearly too long.
So rename it to what it is called in the processor manual.
"v_vmsave_vmload" is a bit shorter, after all.
We could go more aggressively here but having it the same as in the
processor manual is advantageous.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Radim Krčmář <rkrcmar@redhat.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm-ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170801185552.GA3743@nazgul.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
According to Intel 64 and IA-32 Architectures SDM, Volume 3,
Chapter 14.2, "Software needs to exercise care to avoid delays
between the two RDMSRs (for example interrupts)".
So, disable interrupts during reading MSRs IA32_APERF and IA32_MPERF.
See also: commit 4ab60c3f32 (cpufreq: intel_pstate: Disable
interrupts during MSRs reading).
Signed-off-by: Doug Smythies <dsmythies@telus.net>
Reviewed-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Hyper-V host can suggest us to use hypercall for doing remote TLB flush,
this is supposed to work faster than IPIs.
Implementation details: to do HvFlushVirtualAddress{Space,List} hypercalls
we need to put the input somewhere in memory and we don't really want to
have memory allocation on each call so we pre-allocate per cpu memory areas
on boot.
pv_ops patching is happening very early so we need to separate
hyperv_setup_mmu_ops() and hyper_alloc_mmu().
It is possible and easy to implement local TLB flushing too and there is
even a hint for that. However, I don't see a room for optimization on the
host side as both hypercall and native tlb flush will result in vmexit. The
hint is also not set on modern Hyper-V versions.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-8-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For systems with X86_FEATURE_TOPOEXT, current logic uses the APIC ID
to calculate shared_cpu_map. However, APIC IDs are not guaranteed to
be contiguous for cores across different L3s (e.g. family17h system
w/ downcore configuration). This breaks the logic, and results in an
incorrect L3 shared_cpu_map.
Instead, always use the previously calculated cpu_llc_shared_mask of
each CPU to derive the L3 shared_cpu_map.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
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/20170731085159.9455-3-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Current cpu_core_id fixup causes downcored F17h configurations to be
incorrect:
NODE: 0
processor 0 core id : 0
processor 1 core id : 1
processor 2 core id : 2
processor 3 core id : 4
processor 4 core id : 5
processor 5 core id : 0
NODE: 1
processor 6 core id : 2
processor 7 core id : 3
processor 8 core id : 4
processor 9 core id : 0
processor 10 core id : 1
processor 11 core id : 2
Code that relies on the cpu_core_id, like match_smt(), for example,
which builds the thread siblings masks used by the scheduler, is
mislead.
So, limit the fixup to pre-F17h machines. The new value for cpu_core_id
for F17h and later will represent the CPUID_Fn8000001E_EBX[CoreId],
which is guaranteed to be unique for each core within a socket.
This way we have:
NODE: 0
processor 0 core id : 0
processor 1 core id : 1
processor 2 core id : 2
processor 3 core id : 4
processor 4 core id : 5
processor 5 core id : 6
NODE: 1
processor 6 core id : 8
processor 7 core id : 9
processor 8 core id : 10
processor 9 core id : 12
processor 10 core id : 13
processor 11 core id : 14
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
[ Heavily massaged. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Link: http://lkml.kernel.org/r/20170731085159.9455-2-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So I was looking at text_poke_bp() today and I couldn't make sense of
the barriers there.
How's for something like so?
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
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: masami.hiramatsu.pt@hitachi.com
Link: http://lkml.kernel.org/r/20170731102154.f57cvkjtnbmtctk6@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Switching FS and GS is a mess, and the current code is still subtly
wrong: it assumes that "Loading a nonzero value into FS sets the
index and base", which is false on AMD CPUs if the value being
loaded is 1, 2, or 3.
(The current code came from commit 3e2b68d752 ("x86/asm,
sched/x86: Rewrite the FS and GS context switch code"), which made
it better but didn't fully fix it.)
Rewrite it to be much simpler and more obviously correct. This
should fix it fully on AMD CPUs and shouldn't adversely affect
performance.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chang Seok <chang.seok.bae@intel.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>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In ELF_COPY_CORE_REGS, we're copying from the current task, so
accessing thread.fsbase and thread.gsbase makes no sense. Just read
the values from the CPU registers.
In practice, the old code would have been correct most of the time
simply because thread.fsbase and thread.gsbase usually matched the
CPU registers.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chang Seok <chang.seok.bae@intel.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>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
execve used to leak FSBASE and GSBASE on AMD CPUs. Fix it.
The security impact of this bug is small but not quite zero -- it
could weaken ASLR when a privileged task execs a less privileged
program, but only if program changed bitness across the exec, or the
child binary was highly unusual or actively malicious. A child
program that was compromised after the exec would not have access to
the leaked base.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chang Seok <chang.seok.bae@intel.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>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A hang on CPU0 onlining after a preceding offlining is observed. Trace
shows that CPU0 is stuck in check_tsc_sync_target() waiting for source
CPU to run check_tsc_sync_source() but this never happens. Source CPU,
in its turn, is stuck on synchronize_sched() which is called from
native_cpu_up() -> do_boot_cpu() -> unregister_nmi_handler().
So it's a classic ABBA deadlock, due to the use of synchronize_sched() in
unregister_nmi_handler().
Fix the bug by moving unregister_nmi_handler() from do_boot_cpu() to
native_cpu_up() after cpu onlining is done.
Signed-off-by: Vitaly Kuznetsov <vkuznets@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/20170803105818.9934-1-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
To support implementing remote TLB flushing on Hyper-V with a hypercall
we need to make vp_index available outside of vmbus module. Rename and
globalize.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-7-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rep hypercalls are normal hypercalls which perform multiple actions at
once. Hyper-V guarantees to return exectution to the caller in not more
than 50us and the caller needs to use hypercall continuation. Touch NMI
watchdog between hypercall invocations.
This is going to be used for HvFlushVirtualAddressList hypercall for
remote TLB flushing.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-6-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Hyper-V supports 'fast' hypercalls when all parameters are passed through
registers. Implement an inline version of a simpliest of these calls:
hypercall with one 8-byte input and no output.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-4-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We have only three call sites for hv_do_hypercall() and we're going to
change HVCALL_SIGNAL_EVENT to doing fast hypercall so we can inline this
function for optimization.
Hyper-V top level functional specification states that r9-r11 registers
and flags may be clobbered by the hypervisor during hypercall and with
inlining this is somewhat important, add the clobbers.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-3-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Code is arch/x86/hyperv/ is only needed when CONFIG_HYPERV is set, the
'basic' support and detection lives in arch/x86/kernel/cpu/mshyperv.c
which is included when CONFIG_HYPERVISOR_GUEST is set.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-2-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is the same as commit 147277540b ("kvm: svm: Add support for
additional SVM NPF error codes", 2016-11-23), but for Intel processors.
In this case, the exit qualification field's bit 8 says whether the
EPT violation occurred while translating the guest's final physical
address or rather while translating the guest page tables.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 147277540b ("kvm: svm: Add support for additional SVM NPF error
codes", 2016-11-23) added a new error code to aid nested page fault
handling. The commit unprotects (kvm_mmu_unprotect_page) the page when
we get a NPF due to guest page table walk where the page was marked RO.
However, if an L0->L2 shadow nested page table can also be marked read-only
when a page is read only in L1's nested page table. If such a page
is accessed by L2 while walking page tables it can cause a nested
page fault (page table walks are write accesses). However, after
kvm_mmu_unprotect_page we may get another page fault, and again in an
endless stream.
To cover this use case, we qualify the new error_code check with
vcpu->arch.mmu_direct_map so that the error_code check would run on L1
guest, and not the L2 guest. This avoids hitting the above scenario.
Fixes: 147277540b
Cc: stable@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reported by syzkaller:
The kvm-intel.unrestricted_guest=0
WARNING: CPU: 5 PID: 1014 at /home/kernel/data/kvm/arch/x86/kvm//x86.c:7227 kvm_arch_vcpu_ioctl_run+0x38b/0x1be0 [kvm]
CPU: 5 PID: 1014 Comm: warn_test Tainted: G W OE 4.13.0-rc3+ #8
RIP: 0010:kvm_arch_vcpu_ioctl_run+0x38b/0x1be0 [kvm]
Call Trace:
? put_pid+0x3a/0x50
? rcu_read_lock_sched_held+0x79/0x80
? kmem_cache_free+0x2f2/0x350
kvm_vcpu_ioctl+0x340/0x700 [kvm]
? kvm_vcpu_ioctl+0x340/0x700 [kvm]
? __fget+0xfc/0x210
do_vfs_ioctl+0xa4/0x6a0
? __fget+0x11d/0x210
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x23/0xc2
? __this_cpu_preempt_check+0x13/0x20
The syszkaller folks reported a residual mmio emulation request to userspace
due to vm86 fails to emulate inject real mode interrupt(fails to read CS) and
incurs a triple fault. The vCPU returns to userspace with vcpu->mmio_needed == true
and KVM_EXIT_SHUTDOWN exit reason. However, the syszkaller testcase constructs
several threads to launch the same vCPU, the thread which lauch this vCPU after
the thread whichs get the vcpu->mmio_needed == true and KVM_EXIT_SHUTDOWN will
trigger the warning.
#define _GNU_SOURCE
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/kvm.h>
#include <stdio.h>
int kvmcpu;
struct kvm_run *run;
void* thr(void* arg)
{
int res;
res = ioctl(kvmcpu, KVM_RUN, 0);
printf("ret1=%d exit_reason=%d suberror=%d\n",
res, run->exit_reason, run->internal.suberror);
return 0;
}
void test()
{
int i, kvm, kvmvm;
pthread_t th[4];
kvm = open("/dev/kvm", O_RDWR);
kvmvm = ioctl(kvm, KVM_CREATE_VM, 0);
kvmcpu = ioctl(kvmvm, KVM_CREATE_VCPU, 0);
run = (struct kvm_run*)mmap(0, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, kvmcpu, 0);
srand(getpid());
for (i = 0; i < 4; i++) {
pthread_create(&th[i], 0, thr, 0);
usleep(rand() % 10000);
}
for (i = 0; i < 4; i++)
pthread_join(th[i], 0);
}
int main()
{
for (;;) {
int pid = fork();
if (pid < 0)
exit(1);
if (pid == 0) {
test();
exit(0);
}
int status;
while (waitpid(pid, &status, __WALL) != pid) {}
}
return 0;
}
This patch fixes it by resetting the vcpu->mmio_needed once we receive
the triple fault to avoid the residue.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since the kernel segment registers are not prepared at the
entry of irq-entry code, if a kprobe on such code is
jump-optimized, accessing per-CPU variables may cause a
kernel panic.
However, if the kprobe is not optimized, it triggers an int3
exception and sets segment registers correctly.
With this patch we check the probe-address and if it is in the
irq-entry code, it prohibits optimizing such kprobes.
This means we can continue probing such interrupt handlers by kprobes
but it is not optimized anymore.
Reported-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Tested-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S . Miller <davem@davemloft.net>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-arch@vger.kernel.org
Cc: linux-cris-kernel@axis.com
Cc: mathieu.desnoyers@efficios.com
Link: http://lkml.kernel.org/r/150172795654.27216.9824039077047777477.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Generate irqentry and softirqentry text sections without
any Kconfig dependencies. This will add extra sections, but
there should be no performace impact.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S . Miller <davem@davemloft.net>
Cc: Francis Deslauriers <francis.deslauriers@efficios.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-arch@vger.kernel.org
Cc: linux-cris-kernel@axis.com
Cc: mathieu.desnoyers@efficios.com
Link: http://lkml.kernel.org/r/150172789110.27216.3955739126693102122.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make this structure const as it is only used during copy operation.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: julia.lawall@lip6.fr
Link: http://lkml.kernel.org/r/1502039720-4471-1-git-send-email-bhumirks@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Subarchitecture support (mflags-y) was removed from x86 in this commit:
6bda2c8b32 ("x86: remove subarchitecture support")
So drop the mflags-y usage from the Makefile.
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.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/1502105384-23214-1-git-send-email-caoj.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Apparently the binutils 2.20 assembler can't handle the '&&' operator in
the UNWIND_HINT_REGS macro. Rearrange the macro to do without it.
This fixes the following error:
arch/x86/entry/entry_64.S: Assembler messages:
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
arch/x86/entry/entry_64.S:521: Error: non-constant expression in ".if" statement
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 39358a033b ("objtool, x86: Add facility for asm code to provide unwind hints")
Link: http://lkml.kernel.org/r/e2ad97c1ae49a484644b4aaa4dd3faa4d6d969b2.1502116651.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The segment register high words on x86_32 may contain garbage.
Teach regs_get_register() to read them as u16 instead of unsigned
long.
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: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/0b76f6dbe477b7b1a81938fddcc3c483d48f0ff2.1502314765.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Xen's raw SYSCALL entries are much less weird than native. Rather
than fudging them to look like native entries, use the Xen-provided
stack frame directly.
This lets us eliminate entry_SYSCALL_64_after_swapgs and two uses of
the SWAPGS_UNSAFE_STACK paravirt hook. The SYSENTER code would
benefit from similar treatment.
This makes one change to the native code path: the compat
instruction that clears the high 32 bits of %rax is moved slightly
later. I'd be surprised if this affects performance at all.
Tested-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/7c88ed36805d36841ab03ec3b48b4122c4418d71.1502164668.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This closes a hole in our SMAP implementation.
This patch comes from grsecurity. Good catch!
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: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/314cc9f294e8f14ed85485727556ad4f15bb1659.1502159503.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In Family 17h, the number of cores sharing a cache level is obtained
from the Cache Properties CPUID leaf (0x8000001d) by passing in the
cache level in ECX. In prior families, a cache level of 2 was used to
determine this information.
To get the right information, irrespective of Family, iterate over
the cache levels using CPUID 0x8000001d. The last level cache is the
last value to return a non-zero value in EAX.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/5ab569025b39cdfaeca55b571d78c0fc800bdb69.1497452002.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In Family 17h, L3 is the last level cache as opposed to L2 in previous
families. Avoid this name confusion and rename X86_FEATURE_PERFCTR_L2 to
X86_FEATURE_PERFCTR_LLC to indicate the performance counter on the last
level of cache.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/016311029fdecdc3fdc13b7ed865c6cbf48b2f15.1497452002.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vince reported the following rdpmc() testcase failure:
> Failing test case:
>
> fd=perf_event_open();
> addr=mmap(fd);
> exec() // without closing or unmapping the event
> fd=perf_event_open();
> addr=mmap(fd);
> rdpmc() // GPFs due to rdpmc being disabled
The problem is of course that exec() plays tricks with what is
current->mm, only destroying the old mappings after having
installed the new mm.
Fix this confusion by passing along vma->vm_mm instead of relying on
current->mm.
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: 1e0fb9ec67 ("perf: Add pmu callbacks to track event mapping and unmapping")
Link: http://lkml.kernel.org/r/20170802173930.cstykcqefmqt7jau@hirez.programming.kicks-ass.net
[ Minor cleanups. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This work implements jiting of BPF_J{LT,LE,SLT,SLE} instructions
with BPF_X/BPF_K variants for the x86_64 eBPF JIT.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It was reported that the sha1 AVX2 function(sha1_transform_avx2) is
reading ahead beyond its intended data, and causing a crash if the next
block is beyond page boundary:
http://marc.info/?l=linux-crypto-vger&m=149373371023377
This patch makes sure that there is no overflow for any buffer length.
It passes the tests written by Jan Stancek that revealed this problem:
https://github.com/jstancek/sha1-avx2-crash
I have re-enabled sha1-avx2 by reverting commit
b82ce24426
Cc: <stable@vger.kernel.org>
Fixes: b82ce24426 ("crypto: sha1-ssse3 - Disable avx2")
Originally-by: Ilya Albrekht <ilya.albrekht@intel.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Megha Dey <megha.dey@linux.intel.com>
Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
get_cpl requires vcpu_load, so we must cache the result (whether the
vcpu was preempted when its cpl=0) in kvm_vcpu_arch.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If a vcpu exits due to request a user mode spinlock, then
the spinlock-holder may be preempted in user mode or kernel mode.
(Note that not all architectures trap spin loops in user mode,
only AMD x86 and ARM/ARM64 currently do).
But if a vcpu exits in kernel mode, then the holder must be
preempted in kernel mode, so we should choose a vcpu in kernel mode
as a more likely candidate for the lock holder.
This introduces kvm_arch_vcpu_in_kernel() to decide whether the
vcpu is in kernel-mode when it's preempted. kvm_vcpu_on_spin's
new argument says the same of the spinning VCPU.
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add guest_cpuid_clear() and use it instead of kvm_find_cpuid_entry().
Also replace some uses of kvm_find_cpuid_entry() with guest_cpuid_has().
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch turns guest_cpuid_has_XYZ(cpuid) into guest_cpuid_has(cpuid,
X86_FEATURE_XYZ), which gets rid of many very similar helpers.
When seeing a X86_FEATURE_*, we can know which cpuid it belongs to, but
this information isn't in common code, so we recreate it for KVM.
Add some BUILD_BUG_ONs to make sure that it runs nicely.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
bit(X86_FEATURE_NRIPS) is 3 since 2ccd71f1b2 ("x86/cpufeature: Move
some of the scattered feature bits to x86_capability"), so we can
simplify the code.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When L2 uses vmfunc, L0 utilizes the associated vmexit to
emulate a switching of the ept pointer by reloading the
guest MMU.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bandan Das <bsd@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Expose VMFUNC in MSRs and VMCS fields. No actual VMFUNCs are enabled.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bandan Das <bsd@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Enable VMFUNC in the secondary execution controls. This simplifies the
changes necessary to expose it to nested hypervisors. VMFUNCs still
cause #UD when invoked.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bandan Das <bsd@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Let's also just use the underlying functions directly here.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
[Rebased on top of 9f744c5974 ("KVM: nVMX: do not pin the VMCS12")]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
nested_get_page() just sounds confusing. All we want is a page from G1.
This is even unrelated to nested.
Let's introduce kvm_vcpu_gpa_to_page() so we don't get too lengthy
lines.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[Squash pasto fix from Wanpeng Li. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Expose the "Enable INVPCID" secondary execution control to the guest
and properly reflect the exit reason.
In addition, before this patch the guest was always running with
INVPCID enabled, causing pcid.flat's "Test on INVPCID when disabled"
test to fail.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It has been experimentally confirmed that supporting these two MSRs is one
of the necessary conditions for nested Hyper-V to use the TSC page. Modern
Windows guests are noticeably slower when they fall back to reading
timestamps from the HV_X64_MSR_TIME_REF_COUNT MSR instead of using the TSC
page.
The newly supported MSRs are advertised with the AccessFrequencyRegs
partition privilege flag and CPUID.40000003H:EDX[8] "Support for
determining timer frequencies is available" (both outside of the scope of
this KVM patch).
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
ARM:
- Yet another race with VM destruction plugged
- A set of small vgic fixes
x86:
- Preserve pending INIT
- RCU fixes in paravirtual async pf, VM teardown, and VMXOFF emulation
- nVMX interrupt injection and dirty tracking fixes
- initialize to make UBSAN happy
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář:
"ARM:
- Yet another race with VM destruction plugged
- A set of small vgic fixes
x86:
- Preserve pending INIT
- RCU fixes in paravirtual async pf, VM teardown, and VMXOFF
emulation
- nVMX interrupt injection and dirty tracking fixes
- initialize to make UBSAN happy"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: arm/arm64: vgic: Use READ_ONCE fo cmpxchg
KVM: nVMX: Fix interrupt window request with "Acknowledge interrupt on exit"
KVM: nVMX: mark vmcs12 pages dirty on L2 exit
kvm: nVMX: don't flush VMCS12 during VMXOFF or VCPU teardown
KVM: nVMX: do not pin the VMCS12
KVM: avoid using rcu_dereference_protected
KVM: X86: init irq->level in kvm_pv_kick_cpu_op
KVM: X86: Fix loss of pending INIT due to race
KVM: async_pf: make rcu irq exit if not triggered from idle task
KVM: nVMX: fixes to nested virt interrupt injection
KVM: nVMX: do not fill vm_exit_intr_error_code in prepare_vmcs12
KVM: arm/arm64: Handle hva aging while destroying the vm
KVM: arm/arm64: PMU: Fix overflow interrupt injection
KVM: arm/arm64: Fix bug in advertising KVM_CAP_MSI_DEVID capability
Pull x86 fix from Thomas Gleixner:
"The recent irq core changes unearthed API abuse in the HPET code,
which manifested itself in a suspend/resume regression.
The fix replaces the cruft with the proper function calls and cures
the regression"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hpet: Cure interface abuse in the resume path
There are quite a number of occurrences in the kernel of the pattern
if (dst != src)
memcpy(dst, src, walk.total % AES_BLOCK_SIZE);
crypto_xor(dst, final, walk.total % AES_BLOCK_SIZE);
or
crypto_xor(keystream, src, nbytes);
memcpy(dst, keystream, nbytes);
where crypto_xor() is preceded or followed by a memcpy() invocation
that is only there because crypto_xor() uses its output parameter as
one of the inputs. To avoid having to add new instances of this pattern
in the arm64 code, which will be refactored to implement non-SIMD
fallbacks, add an alternative implementation called crypto_xor_cpy(),
taking separate input and output arguments. This removes the need for
the separate memcpy().
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We're about to amend ACPI bus scan with DMI checks whether we're running
on a Mac to support Apple device properties in AML. The DMI checks are
performed for every single device, adding overhead for everything x86
that isn't Apple, which is the majority. Rafael and Andy therefore
request to perform the DMI match only once and cache the result.
Outside of ACPI various other Apple DMI checks exist and it seems
reasonable to use the cached value there as well. Rafael, Andy and
Darren suggest performing the DMI check in arch code and making it
available with a header in include/linux/platform_data/x86/.
To this end, add early_platform_quirks() to arch/x86/kernel/quirks.c
to perform the DMI check and invoke it from setup_arch(). Switch over
all existing Apple DMI checks, thereby fixing two deficiencies:
* They are now #defined to false on non-x86 arches and can thus be
optimized away if they're located in cross-arch code.
* Some of them only match "Apple Inc." but not "Apple Computer, Inc.",
which is used by BIOSes released between January 2006 (when the first
x86 Macs started shipping) and January 2007 (when the company name
changed upon introduction of the iPhone).
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Suggested-by: Darren Hart <dvhart@infradead.org>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
------------[ cut here ]------------
WARNING: CPU: 5 PID: 2288 at arch/x86/kvm/vmx.c:11124 nested_vmx_vmexit+0xd64/0xd70 [kvm_intel]
CPU: 5 PID: 2288 Comm: qemu-system-x86 Not tainted 4.13.0-rc2+ #7
RIP: 0010:nested_vmx_vmexit+0xd64/0xd70 [kvm_intel]
Call Trace:
vmx_check_nested_events+0x131/0x1f0 [kvm_intel]
? vmx_check_nested_events+0x131/0x1f0 [kvm_intel]
kvm_arch_vcpu_ioctl_run+0x5dd/0x1be0 [kvm]
? vmx_vcpu_load+0x1be/0x220 [kvm_intel]
? kvm_arch_vcpu_load+0x62/0x230 [kvm]
kvm_vcpu_ioctl+0x340/0x700 [kvm]
? kvm_vcpu_ioctl+0x340/0x700 [kvm]
? __fget+0xfc/0x210
do_vfs_ioctl+0xa4/0x6a0
? __fget+0x11d/0x210
SyS_ioctl+0x79/0x90
do_syscall_64+0x8f/0x750
? trace_hardirqs_on_thunk+0x1a/0x1c
entry_SYSCALL64_slow_path+0x25/0x25
This can be reproduced by booting L1 guest w/ 'noapic' grub parameter, which
means that tells the kernel to not make use of any IOAPICs that may be present
in the system.
Actually external_intr variable in nested_vmx_vmexit() is the req_int_win
variable passed from vcpu_enter_guest() which means that the L0's userspace
requests an irq window. I observed the scenario (!kvm_cpu_has_interrupt(vcpu) &&
L0's userspace reqeusts an irq window) is true, so there is no interrupt which
L1 requires to inject to L2, we should not attempt to emualte "Acknowledge
interrupt on exit" for the irq window requirement in this scenario.
This patch fixes it by not attempt to emulate "Acknowledge interrupt on exit"
if there is no L1 requirement to inject an interrupt to L2.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
[Added code comment to make it obvious that the behavior is not correct.
We should do a userspace exit with open interrupt window instead of the
nested VM exit. This patch still improves the behavior, so it was
accepted as a (temporary) workaround.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The host physical addresses of L1's Virtual APIC Page and Posted
Interrupt descriptor are loaded into the VMCS02. The CPU may write
to these pages via their host physical address while L2 is running,
bypassing address-translation-based dirty tracking (e.g. EPT write
protection). Mark them dirty on every exit from L2 to prevent them
from getting out of sync with dirty tracking.
Also mark the virtual APIC page and the posted interrupt descriptor
dirty when KVM is virtualizing posted interrupt processing.
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
According to the Intel SDM, software cannot rely on the current VMCS to be
coherent after a VMXOFF or shutdown. So this is a valid way to handle VMCS12
flushes.
24.11.1 Software Use of Virtual-Machine Control Structures
...
If a logical processor leaves VMX operation, any VMCSs active on
that logical processor may be corrupted (see below). To prevent
such corruption of a VMCS that may be used either after a return
to VMX operation or on another logical processor, software should
execute VMCLEAR for that VMCS before executing the VMXOFF instruction
or removing power from the processor (e.g., as part of a transition
to the S3 and S4 power states).
...
This fixes a "suspicious rcu_dereference_check() usage!" warning during
kvm_vm_release() because nested_release_vmcs12() calls
kvm_vcpu_write_guest_page() without holding kvm->srcu.
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Since the current implementation of VMCS12 does a memcpy in and out
of guest memory, we do not need current_vmcs12 and current_vmcs12_page
anymore. current_vmptr is enough to read and write the VMCS12.
And David Matlack noted:
This patch also fixes dirty tracking (memslot->dirty_bitmap) of the
VMCS12 page by using kvm_write_guest. nested_release_page() only marks
the struct page dirty.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Added David Matlack's note and nested_release_page_clean() fix.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
'lapic_irq' is a local variable and its 'level' field isn't
initialized, so 'level' is random, it doesn't matter but
makes UBSAN unhappy:
UBSAN: Undefined behaviour in .../lapic.c:...
load of value 10 is not a valid value for type '_Bool'
...
Call Trace:
[<ffffffff81f030b6>] dump_stack+0x1e/0x20
[<ffffffff81f03173>] ubsan_epilogue+0x12/0x55
[<ffffffff81f03b96>] __ubsan_handle_load_invalid_value+0x118/0x162
[<ffffffffa1575173>] kvm_apic_set_irq+0xc3/0xf0 [kvm]
[<ffffffffa1575b20>] kvm_irq_delivery_to_apic_fast+0x450/0x910 [kvm]
[<ffffffffa15858ea>] kvm_irq_delivery_to_apic+0xfa/0x7a0 [kvm]
[<ffffffffa1517f4e>] kvm_emulate_hypercall+0x62e/0x760 [kvm]
[<ffffffffa113141a>] handle_vmcall+0x1a/0x30 [kvm_intel]
[<ffffffffa114e592>] vmx_handle_exit+0x7a2/0x1fa0 [kvm_intel]
...
Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
When SMP VM start, AP may lost INIT because of receiving INIT between
kvm_vcpu_ioctl_x86_get/set_vcpu_events.
vcpu 0 vcpu 1
kvm_vcpu_ioctl_x86_get_vcpu_events
events->smi.latched_init = 0
send INIT to vcpu1
set vcpu1's pending_events
kvm_vcpu_ioctl_x86_set_vcpu_events
if (events->smi.latched_init == 0)
clear INIT in pending_events
This patch fixes it by just update SMM related flags if we are in SMM.
Thanks Peng Hao for the report and original commit message.
Reported-by: Peng Hao <peng.hao2@zte.com.cn>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
CPUID.(EAX=0x10, ECX=res#):EBX[31:0] reports a bit mask for a resource.
Each set bit within the length of the CBM indicates the corresponding
unit of the resource allocation may be used by other entities in the
platform (e.g. an integrated graphics engine or hardware units outside
the processor core and have direct access to the resource). Each
cleared bit within the length of the CBM indicates the corresponding
allocation unit can be configured to implement a priority-based
allocation scheme without interference with other hardware agents in
the system. Bits outside the length of the CBM are reserved.
More details on the bit mask are described in x86 Software Developer's
Manual.
The bitmask is shown in "info" directory for each resource. It's
up to user to decide how to use the bitmask within a CBM in a partition
to share or isolate a resource with other executing units.
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: vikas.shivappa@linux.intel.com
Link: http://lkml.kernel.org/r/20170725223904.12996-1-tony.luck@intel.com
Add a mon_data directory for the root rdtgroup and all other rdtgroups.
The directory holds all of the monitored data for all domains and events
of all resources being monitored.
The mon_data itself has a list of directories in the format
mon_<domain_name>_<domain_id>. Each of these subdirectories contain one
file per event in the mode "0444". Reading the file displays a snapshot
of the monitored data for the event the file represents.
For ex, on a 2 socket Broadwell with llc_occupancy being
monitored the mon_data contents look as below:
$ ls /sys/fs/resctrl/p1/mon_data/
mon_L3_00
mon_L3_01
Each domain directory has one file per event:
$ ls /sys/fs/resctrl/p1/mon_data/mon_L3_00/
llc_occupancy
To read current llc_occupancy of ctrl_mon group p1
$ cat /sys/fs/resctrl/p1/mon_data/mon_L3_00/llc_occupancy
33789096
[This patch idea is based on Tony's sample patches to organise data in a
per domain directory and have one file per event (and use the fp->priv to
store mon data bits)]
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-20-git-send-email-vikas.shivappa@linux.intel.com
The cpus file is extended to support resource monitoring. This is used
to over-ride the RMID of the default group when running on specific
CPUs. It works similar to the resource control. The "cpus" and
"cpus_list" file is present in default group, ctrl_mon groups and
monitor groups.
Each "cpus" file or cpu_list file reads a cpumask or list showing which
CPUs belong to the resource group. By default all online cpus belong to
the default root group. A CPU can be present in one "ctrl_mon" and one
"monitor" group simultaneously. They can be added to a resource group by
writing the CPU to the file. When a CPU is added to a ctrl_mon group it
is automatically removed from the previous ctrl_mon group. A CPU can be
added to a monitor group only if it is present in the parent ctrl_mon
group and when a CPU is added to a monitor group, it is automatically
removed from the previous monitor group. When CPUs go offline, they are
automatically removed from the ctrl_mon and monitor groups.
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-18-git-send-email-vikas.shivappa@linux.intel.com
The root directory, ctrl_mon and monitor groups are populated
with a read/write file named "tasks". When read, it shows all the task
IDs assigned to the resource group.
Tasks can be added to groups by writing the PID to the file. A task can
be present in one "ctrl_mon" group "and" one "monitor" group. IOW a
PID_x can be seen in a ctrl_mon group and a monitor group at the same
time. When a task is added to a ctrl_mon group, it is automatically
removed from the previous ctrl_mon group where it belonged. Similarly if
a task is moved to a monitor group it is removed from the previous
monitor group . Also since the monitor groups can only have subset of
tasks of parent ctrl_mon group, a task can be moved to a monitor group
only if its already present in the parent ctrl_mon group.
Task membership is indicated by a new field in the task_struct "u32
rmid" which holds the RMID for the task. RMID=0 is reserved for the
default root group where the tasks belong to at mount.
[tony: zero the rmid if rdtgroup was deleted when task was being moved]
Signed-off-by: Tony Luck <tony.luck@linux.intel.com>
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-16-git-send-email-vikas.shivappa@linux.intel.com
Resource control groups can be created using mkdir in resctrl
fs(rdtgroup). In order to extend the resctrl interface to support
monitoring the control groups, extend the current mkdir to support
resource monitoring also.
This allows the rdtgroup created under the root directory to be able to
both control and monitor resources (ctrl_mon group). The ctrl_mon groups
are associated with one CLOSID like the legacy rdtgroups and one
RMID(Resource monitoring ID) as well. Hardware uses RMID to track the
resource usage. Once either of the CLOSID or RMID are exhausted, the
mkdir fails with -ENOSPC. If there are RMIDs in limbo list but not free
an -EBUSY is returned. User can also monitor a subset of the ctrl_mon
rdtgroup's tasks/cpus using the monitor groups. The monitor groups are
created using mkdir under the "mon_groups" directory in every ctrl_mon
group.
[Merged Tony's code: Removed a lot of common mkdir code, a fix to handling
of the list of the child rdtgroups and some cleanups in list
traversal. Also the changes to have similar alloc and free for CLOS/RMID
and return -EBUSY when RMIDs are in limbo and not free]
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-14-git-send-email-vikas.shivappa@linux.intel.com
The info directory files and base files need to be different for each
resource like cache and Memory bandwidth. With in each resource, the
files would be further different for monitoring and ctrl. This leads to
a lot of different static array declarations given that we are adding
resctrl monitoring.
Simplify this to one common list of files and then declare a set of
flags to choose the files based on the resource, whether it is info or
base and if it is control type file. This is as a preparation to include
monitoring based info and base files.
No functional change.
[Vikas: Extended the flags to have few bits per category like resource,
info/base etc]
Signed-off-by: Tony luck <tony.luck@intel.com>
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-11-git-send-email-vikas.shivappa@linux.intel.com
Hardware uses RMID(Resource monitoring ID) to keep track of each of the
RDT events associated with tasks. The number of RMIDs is dependent on
the SKU and is enumerated via CPUID. We add support to manage the RMIDs
which include managing the RMID allocation and reading LLC occupancy
for an RMID.
RMID allocation is managed by keeping a free list which is initialized
to all available RMIDs except for RMID 0 which is always reserved for
root group. RMIDs goto a limbo list once they are
freed since the RMIDs are still tagged to cache lines of the tasks which
were using them - thereby still having some occupancy. They continue to
be in limbo list until the occupancy < threshold_occupancy. The
threshold_occupancy is a user configurable value.
OS uses IA32_QM_CTR MSR to read the occupancy associated with an RMID
after programming the IA32_EVENTSEL MSR with the RMID.
[Tony: Improved limbo search]
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-10-git-send-email-vikas.shivappa@linux.intel.com
'perf cqm' never worked due to the incompatibility between perf
infrastructure and cqm hardware support. The hardware uses RMIDs to
track the llc occupancy of tasks and these RMIDs are per package. This
makes monitoring a hierarchy like cgroup along with monitoring of tasks
separately difficult and several patches sent to lkml to fix them were
NACKed. Further more, the following issues in the current perf cqm make
it almost unusable:
1. No support to monitor the same group of tasks for which we do
allocation using resctrl.
2. It gives random and inaccurate data (mostly 0s) once we run out
of RMIDs due to issues in Recycling.
3. Recycling results in inaccuracy of data because we cannot
guarantee that the RMID was stolen from a task when it was not
pulling data into cache or even when it pulled the least data. Also
for monitoring llc_occupancy, if we stop using an RMID_x and then
start using an RMID_y after we reclaim an RMID from an other event,
we miss accounting all the occupancy that was tagged to RMID_x at a
later perf_count.
2. Recycling code makes the monitoring code complex including
scheduling because the event can lose RMID any time. Since MBM
counters count bandwidth for a period of time by taking snap shot of
total bytes at two different times, recycling complicates the way we
count MBM in a hierarchy. Also we need a spin lock while we do the
processing to account for MBM counter overflow. We also currently
use a spin lock in scheduling to prevent the RMID from being taken
away.
4. Lack of support when we run different kind of event like task,
system-wide and cgroup events together. Data mostly prints 0s. This
is also because we can have only one RMID tied to a cpu as defined
by the cqm hardware but a perf can at the same time tie multiple
events during one sched_in.
5. No support of monitoring a group of tasks. There is partial support
for cgroup but it does not work once there is a hierarchy of cgroups
or if we want to monitor a task in a cgroup and the cgroup itself.
6. No support for monitoring tasks for the lifetime without perf
overhead.
7. It reported the aggregate cache occupancy or memory bandwidth over
all sockets. But most cloud and VMM based use cases want to know the
individual per-socket usage.
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: davidcc@google.com
Cc: reinette.chatre@intel.com
Link: http://lkml.kernel.org/r/1501017287-28083-2-git-send-email-vikas.shivappa@linux.intel.com
WARNING: CPU: 5 PID: 1242 at kernel/rcu/tree_plugin.h:323 rcu_note_context_switch+0x207/0x6b0
CPU: 5 PID: 1242 Comm: unity-settings- Not tainted 4.13.0-rc2+ #1
RIP: 0010:rcu_note_context_switch+0x207/0x6b0
Call Trace:
__schedule+0xda/0xba0
? kvm_async_pf_task_wait+0x1b2/0x270
schedule+0x40/0x90
kvm_async_pf_task_wait+0x1cc/0x270
? prepare_to_swait+0x22/0x70
do_async_page_fault+0x77/0xb0
? do_async_page_fault+0x77/0xb0
async_page_fault+0x28/0x30
RIP: 0010:__d_lookup_rcu+0x90/0x1e0
I encounter this when trying to stress the async page fault in L1 guest w/
L2 guests running.
Commit 9b132fbe54 (Add rcu user eqs exception hooks for async page
fault) adds rcu_irq_enter/exit() to kvm_async_pf_task_wait() to exit cpu
idle eqs when needed, to protect the code that needs use rcu. However,
we need to call the pair even if the function calls schedule(), as seen
from the above backtrace.
This patch fixes it by informing the RCU subsystem exit/enter the irq
towards/away from idle for both n.halted and !n.halted.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
There are three issues in nested_vmx_check_exception:
1) it is not taking PFEC_MATCH/PFEC_MASK into account, as reported
by Wanpeng Li;
2) it should rebuild the interruption info and exit qualification fields
from scratch, as reported by Jim Mattson, because the values from the
L2->L0 vmexit may be invalid (e.g. if an emulated instruction causes
a page fault, the EPT misconfig's exit qualification is incorrect).
3) CR2 and DR6 should not be written for exception intercept vmexits
(CR2 only for AMD).
This patch fixes the first two and adds a comment about the last,
outlining the fix.
Cc: Jim Mattson <jmattson@google.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Do this in the caller of nested_vmx_vmexit instead.
nested_vmx_check_exception was doing a vmwrite to the vmcs02's
VM_EXIT_INTR_ERROR_CODE field, so that prepare_vmcs12 would move
the field to vmcs12->vm_exit_intr_error_code. However that isn't
possible on pre-Haswell machines. Moving the vmcs12 write to the
callers fixes it.
Reported-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[Changed nested_vmx_reflect_vmexit() return type to (int)1 from (bool)1,
thanks to fengguang.wu@intel.com]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
The HPET resume path abuses irq_domain_[de]activate_irq() to restore the
MSI message in the HPET chip for the boot CPU on resume and it relies on an
implementation detail of the interrupt core code, which magically makes the
HPET unmask call invoked via a irq_disable/enable pair. This worked as long
as the irq code did unconditionally invoke the unmask() callback. With the
recent changes which keep track of the masked state to avoid expensive
hardware access, this does not longer work. As a consequence the HPET timer
interrupts are not unmasked which breaks resume as the boot CPU waits
forever that a timer interrupt arrives.
Make the restore of the MSI message explicit and invoke the unmask()
function directly. While at it get rid of the pointless affinity setting as
nothing can change the affinity of the interrupt and the vector across
suspend/resume. The restore of the MSI message reestablishes the previous
affinity setting which is the correct one.
Fixes: bf22ff45be ("genirq: Avoid unnecessary low level irq function calls")
Reported-and-tested-by: Tomi Sarvela <tomi.p.sarvela@intel.com>
Reported-by: Martin Peres <martin.peres@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: jeffy.chen@rock-chips.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1707312158590.2287@nanos
Pull x86 fixes from Thomas Gleixner:
"A small set of x86 fixes:
- prevent the kernel from using the EFI reboot method when EFI is
disabled.
- two patches addressing clang issues"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Disable the address-of-packed-member compiler warning
x86/efi: Fix reboot_mode when EFI runtime services are disabled
x86/boot: #undef memcpy() et al in string.c
