b4ff8389ed is incomplete: relies on nr_legacy_irqs() to get the number
of legacy interrupts when actually nr_legacy_irqs() returns 0 after
probe_8259A(). Use NR_IRQS_LEGACY instead.
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
CC: stable@vger.kernel.org
On slow platforms with unreliable TSC, such as QEMU emulated machines,
it is possible for the kernel to request the next event in the past. In
that case, in the current implementation of xen_vcpuop_clockevent, we
simply return -ETIME. To be precise the Xen returns -ETIME and we pass
it on. However the result of this is a missed event, which simply causes
the kernel to hang.
Instead it is better to always ask the hypervisor for a timer event,
even if the timeout is in the past. That way there are no lost
interrupts and the kernel survives. To do that, remove the
VCPU_SSHOTTMR_future flag.
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com>
Pull x86 fixes from Ingo Molnar:
"Misc fixes: a binutils fix, an lguest fix, an mcelog fix and a missing
documentation fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Avoid using object after free in genpool
lguest, x86/entry/32: Fix handling of guest syscalls using interrupt gates
x86/build: Build compressed x86 kernels as PIE
x86/mm/pkeys: Add missing Documentation
This reverts commit c4004b02f8.
Sadly, my hope that nobody would actually use the special kernel entries
in /proc/iomem were dashed by kexec. Which reads /proc/iomem explicitly
to find the kernel base address. Nasty.
Anyway, that means we can't do the sane and simple thing and just remove
the entries, and we'll instead have to mask them out based on permissions.
Reported-by: Zhengyu Zhang <zhezhang@redhat.com>
Reported-by: Dave Young <dyoung@redhat.com>
Reported-by: Freeman Zhang <freeman.zhang1992@gmail.com>
Reported-by: Emrah Demir <ed@abdsec.com>
Reported-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Wrong indentation in the PMU code from the merge window
- A long-time bug occuring with running ntpd on the host, candidate for stable
- Properly handle (and warn about) the unsupported configuration of running on
systems with less than 40 bits of PA space
- More fixes to the PM and hotplug notifier stuff from the merge window
x86:
- leak of guest xcr0 (typically shows up as SIGILL)
- new maintainer (who is sending the pull request too)
- fix for merge window regression
- fix for guest CPUID
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJXCrBeAAoJEL/70l94x66DHlYIAJseQjhyXMm3J8vkZ1qoPjiM
IWUV3BoSDpMjIXZdiouDShCBwBE1zDoFCXzkGO8FGNpYTy/4WQ2DF+fQr8OFveOv
bpLJI6iYpCESh5ihhp8UDTD9oY4ZAxyPfNUx06Rirze2ijDr6rWkM16bKgdIlMpa
rzGUQWodZO0odCWVMAXSe08uistvqZ71iacpAIJQJrx3MJcq1u2+Y2daZO3df1R6
GnWxY5SK2ZvrNEwjQPXAYgCPGaJKEVUbr9BvWFoQ2O+qGA4TPv4jrOsAQ7bRh4Rr
SGOH465Qdj2EA7eJrP2/NAlD5N7H7RWkiLiyIGF4OTS6wJHU8jdnOLbYPx0VmQg=
=1OKc
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář:
"ARM fixes:
- Wrong indentation in the PMU code from the merge window
- A long-time bug occuring with running ntpd on the host, candidate
for stable
- Properly handle (and warn about) the unsupported configuration of
running on systems with less than 40 bits of PA space
- More fixes to the PM and hotplug notifier stuff from the merge
window
x86:
- leak of guest xcr0 (typically shows up as SIGILL)
- new maintainer (who is sending the pull request too)
- fix for merge window regression
- fix for guest CPUID"
Paolo Bonzini points out:
"For the record, this tag is signed by me because I prepared the pull
request. Further pull requests for 4.6 will be signed and sent out by
Radim directly"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: mask CPUID(0xD,0x1).EAX against host value
kvm: x86: do not leak guest xcr0 into host interrupt handlers
KVM: MMU: fix permission_fault()
KVM: new maintainer on the block
arm64: KVM: unregister notifiers in hyp mode teardown path
arm64: KVM: Warn when PARange is less than 40 bits
KVM: arm/arm64: Handle forward time correction gracefully
arm64: KVM: Add braces to multi-line if statement in virtual PMU code
When we loop over all queued machine check error records to pass them
to the registered notifiers we use llist_for_each_entry(). But the loop
calls gen_pool_free() for the entry in the body of the loop - and then
the iterator looks at node->next after the free.
Use llist_for_each_entry_safe() instead.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Cc: Gong Chen <gong.chen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/0205920@agluck-desk.sc.intel.com
Link: http://lkml.kernel.org/r/1459929916-12852-4-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This ensures that the guest doesn't see XSAVE extensions
(e.g. xgetbv1 or xsavec) that the host lacks.
Cc: stable@vger.kernel.org
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
An interrupt handler that uses the fpu can kill a KVM VM, if it runs
under the following conditions:
- the guest's xcr0 register is loaded on the cpu
- the guest's fpu context is not loaded
- the host is using eagerfpu
Note that the guest's xcr0 register and fpu context are not loaded as
part of the atomic world switch into "guest mode". They are loaded by
KVM while the cpu is still in "host mode".
Usage of the fpu in interrupt context is gated by irq_fpu_usable(). The
interrupt handler will look something like this:
if (irq_fpu_usable()) {
kernel_fpu_begin();
[... code that uses the fpu ...]
kernel_fpu_end();
}
As long as the guest's fpu is not loaded and the host is using eager
fpu, irq_fpu_usable() returns true (interrupted_kernel_fpu_idle()
returns true). The interrupt handler proceeds to use the fpu with
the guest's xcr0 live.
kernel_fpu_begin() saves the current fpu context. If this uses
XSAVE[OPT], it may leave the xsave area in an undesirable state.
According to the SDM, during XSAVE bit i of XSTATE_BV is not modified
if bit i is 0 in xcr0. So it's possible that XSTATE_BV[i] == 1 and
xcr0[i] == 0 following an XSAVE.
kernel_fpu_end() restores the fpu context. Now if any bit i in
XSTATE_BV == 1 while xcr0[i] == 0, XRSTOR generates a #GP. The
fault is trapped and SIGSEGV is delivered to the current process.
Only pre-4.2 kernels appear to be vulnerable to this sequence of
events. Commit 653f52c ("kvm,x86: load guest FPU context more eagerly")
from 4.2 forces the guest's fpu to always be loaded on eagerfpu hosts.
This patch fixes the bug by keeping the host's xcr0 loaded outside
of the interrupts-disabled region where KVM switches into guest mode.
Cc: stable@vger.kernel.org
Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: David Matlack <dmatlack@google.com>
[Move load after goto cancel_injection. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm-unit-tests complained about the PFEC is not set properly, e.g,:
test pte.rw pte.d pte.nx pde.p pde.rw pde.pse user fetch: FAIL: error code 15
expected 5
Dump mapping: address: 0x123400000000
------L4: 3e95007
------L3: 3e96007
------L2: 2000083
It's caused by the reason that PFEC returned to guest is copied from the
PFEC triggered by shadow page table
This patch fixes it and makes the logic of updating errcode more clean
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
[Do not assume pfec.p=1. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- intel_pstate fixes for two issues exposed by the recent switch
over from using timers and for one issue introduced during the
4.4 cycle plus new comments describing data structures used by
the driver (Rafael Wysocki, Srinivas Pandruvada).
- intel_idle fixes related to CPU offline/online (Richard Cochran).
- intel_idle support (new CPU IDs and state definitions mostly) for
Skylake-X and Kabylake processors (Len Brown).
- PCC mailbox driver fix for an out-of-bounds memory access that
may cause the kernel to panic() (Shanker Donthineni).
- New (missing) CPU ID for one apparently overlooked Haswell model
in the Intel RAPL power capping driver (Srinivas Pandruvada).
- Fix for the PM core's wakeup IRQs framework to make it work after
wakeup settings reconfiguration from sysfs (Grygorii Strashko).
- Runtime PM documentation update to make it describe what needs
to be done during device removal more precisely (Krzysztof
Kozlowski).
- Stale comment removal cleanup in the cpufreq-dt driver (Viresh
Kumar).
- turbostat utility fixes and support for Broxton, Skylake-X
and Kabylake processors (Len Brown).
/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=f4MM
-----END PGP SIGNATURE-----
Merge tag 'pm+acpi-4.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI fixes from Rafael Wysocki:
"Fixes for some issues discovered after recent changes and for some
that have just been found lately regardless of those changes
(intel_pstate, intel_idle, PM core, mailbox/pcc, turbostat) plus
support for some new CPU models (intel_idle, Intel RAPL driver,
turbostat) and documentation updates (intel_pstate, PM core).
Specifics:
- intel_pstate fixes for two issues exposed by the recent switch over
from using timers and for one issue introduced during the 4.4 cycle
plus new comments describing data structures used by the driver
(Rafael Wysocki, Srinivas Pandruvada).
- intel_idle fixes related to CPU offline/online (Richard Cochran).
- intel_idle support (new CPU IDs and state definitions mostly) for
Skylake-X and Kabylake processors (Len Brown).
- PCC mailbox driver fix for an out-of-bounds memory access that may
cause the kernel to panic() (Shanker Donthineni).
- New (missing) CPU ID for one apparently overlooked Haswell model in
the Intel RAPL power capping driver (Srinivas Pandruvada).
- Fix for the PM core's wakeup IRQs framework to make it work after
wakeup settings reconfiguration from sysfs (Grygorii Strashko).
- Runtime PM documentation update to make it describe what needs to
be done during device removal more precisely (Krzysztof Kozlowski).
- Stale comment removal cleanup in the cpufreq-dt driver (Viresh
Kumar).
- turbostat utility fixes and support for Broxton, Skylake-X and
Kabylake processors (Len Brown)"
* tag 'pm+acpi-4.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (28 commits)
PM / wakeirq: fix wakeirq setting after wakup re-configuration from sysfs
tools/power turbostat: work around RC6 counter wrap
tools/power turbostat: initial KBL support
tools/power turbostat: initial SKX support
tools/power turbostat: decode BXT TSC frequency via CPUID
tools/power turbostat: initial BXT support
tools/power turbostat: print IRTL MSRs
tools/power turbostat: SGX state should print only if --debug
intel_idle: Add KBL support
intel_idle: Add SKX support
intel_idle: Clean up all registered devices on exit.
intel_idle: Propagate hot plug errors.
intel_idle: Don't overreact to a cpuidle registration failure.
intel_idle: Setup the timer broadcast only on successful driver load.
intel_idle: Avoid a double free of the per-CPU data.
intel_idle: Fix dangling registration on error path.
intel_idle: Fix deallocation order on the driver exit path.
intel_idle: Remove redundant initialization calls.
intel_idle: Fix a helper function's return value.
intel_idle: remove useless return from void function.
...
* pm-core:
PM / wakeirq: fix wakeirq setting after wakup re-configuration from sysfs
PM / runtime: Document steps for device removal
* powercap:
powercap: intel_rapl: Add missing Haswell model
* pm-tools:
tools/power turbostat: work around RC6 counter wrap
tools/power turbostat: initial KBL support
tools/power turbostat: initial SKX support
tools/power turbostat: decode BXT TSC frequency via CPUID
tools/power turbostat: initial BXT support
tools/power turbostat: print IRTL MSRs
tools/power turbostat: SGX state should print only if --debug
Some processors use the Interrupt Response Time Limit (IRTL) MSR value
to describe the maximum IRQ response time latency for deep
package C-states. (Though others have the register, but do not use it)
Lets print it out to give insight into the cases where it is used.
IRTL begain in SNB, with PC3/PC6/PC7, and HSW added PC8/PC9/PC10.
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Let's see if anybody even notices. I doubt anybody uses this, and it
does expose addresses that should be randomized, so let's just remove
the code. It's old and traditional, and it used to be cute, but we
should have removed this long ago.
If it turns out anybody notices and this breaks something, we'll have to
revert this, and maybe we'll end up using other approaches instead
(using %pK or similar). But removing unnecessary code is always the
preferred option.
Noted-by: Emrah Demir <ed@abdsec.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
others are usual stable material.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJXA8x6AAoJEL/70l94x66D0x8H/RcBnc75994RQ++WmHSvD9GF
yruGB8soLDdjX+Oceol0aEPHokrBu3JtcdoTBe0GwbCKV/F5NkQZ4EfLxDtR3tte
7ILkPULLy5GElFpJNQuT4pmXzTEspFvXpqHhFik7WVBga3W9wMFQcjbrgmGBUzLE
p2aJVhZyErpKxGFkUYWhDnlqWsguTTIzv/pqNhLY4VVc0UrXN9AA0fq9RkvgU3KS
Hxk4/A6SV/b7dyzvttzITww0f1iu8FmlLj2TXapIEoOz7AnInD6KIN0RYpxbDjxN
bEzEfpahUtuDeM87/t2kHEj0Gn09iHK7/BbCC1Hrwo1CQhbAQ/D0GIvqYAQixf4=
=NugZ
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"Miscellaneous bugfixes.
The ARM and s390 fixes are for new regressions from the merge window,
others are usual stable material"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
compiler-gcc: disable -ftracer for __noclone functions
kvm: x86: make lapic hrtimer pinned
s390/mm/kvm: fix mis-merge in gmap handling
kvm: set page dirty only if page has been writable
KVM: x86: reduce default value of halt_poll_ns parameter
KVM: Hyper-V: do not do hypercall userspace exits if SynIC is disabled
KVM: x86: Inject pending interrupt even if pending nmi exist
arm64: KVM: Register CPU notifiers when the kernel runs at HYP
arm64: kvm: 4.6-rc1: Fix VTCR_EL2 VS setting
When a vCPU runs on a nohz_full core, the hrtimer used by
the lapic emulation code can be migrated to another core.
When this happens, it's possible to observe milisecond
latency when delivering timer IRQs to KVM guests.
The huge latency is mainly due to the fact that
apic_timer_fn() expects to run during a kvm exit. It
sets KVM_REQ_PENDING_TIMER and let it be handled on kvm
entry. However, if the timer fires on a different core,
we have to wait until the next kvm exit for the guest
to see KVM_REQ_PENDING_TIMER set.
This problem became visible after commit 9642d18ee. This
commit changed the timer migration code to always attempt
to migrate timers away from nohz_full cores. While it's
discussable if this is correct/desirable (I don't think
it is), it's clear that the lapic emulation code has
a requirement on firing the hrtimer in the same core
where it was started. This is achieved by making the
hrtimer pinned.
Lastly, note that KVM has code to migrate timers when a
vCPU is scheduled to run in different core. However, this
forced migration may fail. When this happens, we can have
the same problem. If we want 100% correctness, we'll have
to modify apic_timer_fn() to cause a kvm exit when it runs
on a different core than the vCPU. Not sure if this is
possible.
Here's a reproducer for the issue being fixed:
1. Set all cores but core0 to be nohz_full cores
2. Start a guest with a single vCPU
3. Trace apic_timer_fn() and kvm_inject_apic_timer_irqs()
You'll see that apic_timer_fn() will run in core0 while
kvm_inject_apic_timer_irqs() runs in a different core. If
you get both on core0, try running a program that takes 100%
of the CPU and pin it to core0 to force the vCPU out.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- Safely migrate event channels between CPUs.
- Fix CPU hotplug.
- Maintainer changes.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXAkQtAAoJEFxbo/MsZsTRpAoH/R0mVySTK3RloxRo4SPDWs//
3EIgDFBCde/JfDmhJw7OTLC6oHExq/ObBunV4I6HSStDYjZfHnMXTe7uiRo6oOUt
ql8/k1P4NM202L2qkjZU89ObPwOMbx50NiHtVG3JAIydZc/jgn4/brow9ZymDAUd
lp85Oj0d66uM5iIY9YVa5nY/calt5W0rr9EoV93HSf6GFefNJKXJ5u3KW8IgMyIl
I4/y8GraQLAcXBcmrOny51nlIxsiv1wTssJfExH49/8In3JH3SlbZDGuEiIovPUC
jJ96Tr/oOhFyPZIM3J7pFYpvn4en84V07zbaWcEUmVf8capv3pjwJNg2Xx64FdI=
=bSO5
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.6-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from David Vrabel:
"Regression and bug fixes for 4.6-rc2:
- safely migrate event channels between CPUs
- fix CPU hotplug
- maintainer changes"
* tag 'for-linus-4.6-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
MAINTAINERS: xen: Konrad to step down and Juergen to pick up
xen/events: Mask a moving irq
Xen on ARM and ARM64: update MAINTAINERS info
xen/x86: Call cpu_startup_entry(CPUHP_AP_ONLINE_IDLE) from xen_play_dead()
xen/apic: Provide Xen-specific version of cpu_present_to_apicid APIC op
Pull x86 fixes from Thomas Gleixner:
"This lot contains:
- Some fixups for the fallout of the topology consolidation which
unearthed AMD/Intel inconsistencies
- Documentation for the x86 topology management
- Support for AMD advanced power management bits
- Two simple cleanups removing duplicated code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add advanced power management bits
x86/thread_info: Merge two !__ASSEMBLY__ sections
x86/cpufreq: Remove duplicated TDP MSR macro definitions
x86/Documentation: Start documenting x86 topology
x86/cpu: Get rid of compute_unit_id
perf/x86/amd: Cleanup Fam10h NB event constraints
x86/topology: Fix AMD core count
Just one fix for a nasty boot failure on some systems based on
Intel Skylake that shipped with broken firmware where enabling
hardware-coordinated P-states management (HWP) causes a faulty
interrupt handler in SMM to be invoked and crash the system
(Srinivas Pandruvada).
/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=GJ34
-----END PGP SIGNATURE-----
Merge tag 'pm+acpi-4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI fix from Rafael J. Wysocki:
"Just one fix for a nasty boot failure on some systems based on Intel
Skylake that shipped with broken firmware where enabling
hardware-coordinated P-states management (HWP) causes a faulty
interrupt handler in SMM to be invoked and crash the system (Srinivas
Pandruvada)"
* tag 'pm+acpi-4.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / processor: Request native thermal interrupt handling via _OSC
The recently introduced batched invalidations mechanism uses its own
mechanism for shootdown. However, it does wrong accounting of
interrupts (e.g., inc_irq_stat is called for local invalidations),
trace-points (e.g., TLB_REMOTE_SHOOTDOWN for local invalidations) and
may break some platforms as it bypasses the invalidation mechanisms of
Xen and SGI UV.
This patch reuses the existing TLB flushing mechnaisms instead. We use
NULL as mm to indicate a global invalidation is required.
Fixes 72b252aed5 ("mm: send one IPI per CPU to TLB flush all entries after unmapping pages")
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
TLB_REMOTE_SEND_IPI was recently introduced, but it counts bytes instead
of pages. In addition, it does not report correctly the case in which
flush_tlb_page flushes a page. Fix it to be consistent with other TLB
counters.
Fixes: 5b74283ab2 ("x86, mm: trace when an IPI is about to be sent")
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In absence of shadow dirty mask, there is no need to set page dirty
if page has never been writable. This is a tiny optimization but
good to have for people who care much about dirty page tracking.
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Windows lets applications choose the frequency of the timer tick,
and in Windows 10 the maximum rate was changed from 1024 Hz to
2048 Hz. Unfortunately, because of the way the Windows API
works, most applications who need a higher rate than the default
64 Hz will just do
timeGetDevCaps(&tc, sizeof(tc));
timeBeginPeriod(tc.wPeriodMin);
and pick the maximum rate. This causes very high CPU usage when
playing media or games on Windows 10, even if the guest does not
actually use the CPU very much, because the frequent timer tick
causes halt_poll_ns to kick in.
There is no really good solution, especially because Microsoft
could sooner or later bump the limit to 4096 Hz, but for now
the best we can do is lower a bit the upper limit for
halt_poll_ns. :-(
Reported-by: Jon Panozzo <jonp@lime-technology.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If SynIC is disabled, there is nothing that userspace can do to
handle these exits; on the other hand, userspace probably will
not know about KVM_EXIT_HYPERV_HCALL and complain about it or
even exit. Just prevent anything bad from happening by handling
the hypercall in KVM and returning an "invalid hypercall" code.
Fixes: 83326e43f2
Cc: Andrey Smetanin <irqlevel@gmail.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Non maskable interrupts (NMI) are preferred to interrupts in current
implementation. If a NMI is pending and NMI is blocked by the result
of nmi_allowed(), pending interrupt is not injected and
enable_irq_window() is not executed, even if interrupts injection is
allowed.
In old kernel (e.g. 2.6.32), schedule() is often called in NMI context.
In this case, interrupts are needed to execute iret that intends end
of NMI. The flag of blocking new NMI is not cleared until the guest
execute the iret, and interrupts are blocked by pending NMI. Due to
this, iret can't be invoked in the guest, and the guest is starved
until block is cleared by some events (e.g. canceling injection).
This patch injects pending interrupts, when it's allowed, even if NMI
is blocked. And, If an interrupts is pending after executing
inject_pending_event(), enable_irq_window() is executed regardless of
NMI pending counter.
Cc: stable@vger.kernel.org
Signed-off-by: Yuki Shibuya <shibuya.yk@ncos.nec.co.jp>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This call has always been missing from xen_play dead() but until
recently this was rather benign. With new cpu hotplug framework
(commit 8df3e07e7f ("cpu/hotplug: Let upcoming cpu bring itself fully up").
however this call is required, otherwise a hot-plugged CPU will not
be properly brough up (by never calling cpuhp_online_idle())
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJW9xVQAAoJEHm+PkMAQRiGLCYH/RaD6PE78ttLoAIm2rTUY+P9
jtNhRVVNPmNn6103r0g9RYxyN0k+KyRQiO0I3XC77i30ksJV0duqhZfpg9nyHaFZ
ljiYBLWFcc6qyMiE5B9ogEwveQriKtbUTrIPHer/vEmOdJHDRoUIVZ/qQ+eNzGmq
aHa0bJalCXqkRpXatfZBUz8OyblrNjZMpX6907vqR5kRrcXqRn52X32gmy6bwSRp
oRRQvSjzzZzApISz1uQIY5TFEb9ARrtK2FUf/rM0WS4gE1tB/p8Ccx7iopqk/zjI
f+vZEdQ6o6FdPZ38XZGnwyr1nf52AV5/7wJs+5D1rLCHK8buEJD01BiT7qQvpnI=
=q0+P
-----END PGP SIGNATURE-----
Merge tag 'v4.6-rc1' into for-linus-4.6
Linux 4.6-rc1
* tag 'v4.6-rc1': (12823 commits)
Linux 4.6-rc1
f2fs/crypto: fix xts_tweak initialization
NTB: Remove _addr functions from ntb_hw_amd
orangefs: fix orangefs_superblock locking
orangefs: fix do_readv_writev() handling of error halfway through
orangefs: have ->kill_sb() evict the VFS side of things first
orangefs: sanitize ->llseek()
orangefs-bufmap.h: trim unused junk
orangefs: saner calling conventions for getting a slot
orangefs_copy_{to,from}_bufmap(): don't pass bufmap pointer
orangefs: get rid of readdir_handle_s
thp: fix typo in khugepaged_scan_pmd()
MAINTAINERS: fill entries for KASAN
mm/filemap: generic_file_read_iter(): check for zero reads unconditionally
kasan: test fix: warn if the UAF could not be detected in kmalloc_uaf2
mm, kasan: stackdepot implementation. Enable stackdepot for SLAB
arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
mm, kasan: add GFP flags to KASAN API
mm, kasan: SLAB support
kasan: modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()
...
The 32-bit x86 assembler in binutils 2.26 will generate R_386_GOT32X
relocation to get the symbol address in PIC. When the compressed x86
kernel isn't built as PIC, the linker optimizes R_386_GOT32X relocations
to their fixed symbol addresses. However, when the compressed x86
kernel is loaded at a different address, it leads to the following
load failure:
Failed to allocate space for phdrs
during the decompression stage.
If the compressed x86 kernel is relocatable at run-time, it should be
compiled with -fPIE, instead of -fPIC, if possible and should be built as
Position Independent Executable (PIE) so that linker won't optimize
R_386_GOT32X relocation to its fixed symbol address.
Older linkers generate R_386_32 relocations against locally defined
symbols, _bss, _ebss, _got and _egot, in PIE. It isn't wrong, just less
optimal than R_386_RELATIVE. But the x86 kernel fails to properly handle
R_386_32 relocations when relocating the kernel. To generate
R_386_RELATIVE relocations, we mark _bss, _ebss, _got and _egot as
hidden in both 32-bit and 64-bit x86 kernels.
To build a 64-bit compressed x86 kernel as PIE, we need to disable the
relocation overflow check to avoid relocation overflow errors. We do
this with a new linker command-line option, -z noreloc-overflow, which
got added recently:
commit 4c10bbaa0912742322f10d9d5bb630ba4e15dfa7
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Tue Mar 15 11:07:06 2016 -0700
Add -z noreloc-overflow option to x86-64 ld
Add -z noreloc-overflow command-line option to the x86-64 ELF linker to
disable relocation overflow check. This can be used to avoid relocation
overflow check if there will be no dynamic relocation overflow at
run-time.
The 64-bit compressed x86 kernel is built as PIE only if the linker supports
-z noreloc-overflow. So far 64-bit relocatable compressed x86 kernel
boots fine even when it is built as a normal executable.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
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>
Cc: linux-kernel@vger.kernel.org
[ Edited the changelog and comments. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The list of CPU model specific registers contains two copies of TDP
registers, remove the one, which is out of numerical order in the
list.
Fixes: 6a35fc2d6c ("cpufreq: intel_pstate: get P1 from TAR when available")
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Cc: Len Brown <len.brown@intel.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Kristen Carlson
Accardi <kristen@linux.intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: http://lkml.kernel.org/r/1459018020-24577-1-git-send-email-vladimir_zapolskiy@mentor.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Avoid allocating the AMD NB event constraints data structure when not
needed. This gets rid of x86_max_cores usage and avoids allocating
this on AMD Core Perfctr supporting hardware (which has separate MSRs
for NB events).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: aherrmann@suse.com
Cc: Rui Huang <ray.huang@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: jencce.kernel@gmail.com
Link: http://lkml.kernel.org/r/20160320124629.GY6375@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
It turns out AMD gets x86_max_cores wrong when there are compute
units.
The issue is that Linux assumes:
nr_logical_cpus = nr_cores * nr_siblings
But AMD reports its CU unit as 2 cores, but then sets num_smp_siblings
to 2 as well.
Boris: fixup ras/mce_amd_inj.c too, to compute the Node Base Core
properly, according to the new nomenclature.
Fixes: 1f12e32f4c ("x86/topology: Create logical package id")
Reported-by: Xiong Zhou <jencce.kernel@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andreas Herrmann <aherrmann@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Link: http://lkml.kernel.org/r/20160317095220.GO6344@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Update the definition of memcpy_from_pmem() to return 0 or a negative
error code. Implement x86/arch_memcpy_from_pmem() with memcpy_mcsafe().
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
There are several reports of freeze on enabling HWP (Hardware PStates)
feature on Skylake-based systems by the Intel P-states driver. The root
cause is identified as the HWP interrupts causing BIOS code to freeze.
HWP interrupts use the thermal LVT which can be handled by Linux
natively, but on the affected Skylake-based systems SMM will respond
to it by default. This is a problem for several reasons:
- On the affected systems the SMM thermal LVT handler is broken (it
will crash when invoked) and a BIOS update is necessary to fix it.
- With thermal interrupt handled in SMM we lose all of the reporting
features of the arch/x86/kernel/cpu/mcheck/therm_throt driver.
- Some thermal drivers like x86-package-temp depend on the thermal
threshold interrupts signaled via the thermal LVT.
- The HWP interrupts are useful for debugging and tuning
performance (if the kernel can handle them).
The native handling of thermal interrupts needs to be enabled
because of that.
This requires some way to tell SMM that the OS can handle thermal
interrupts. That can be done by using _OSC/_PDC in processor
scope very early during ACPI initialization.
The meaning of _OSC/_PDC bit 12 in processor scope is whether or
not the OS supports native handling of interrupts for Collaborative
Processor Performance Control (CPPC) notifications. Since on
HWP-capable systems CPPC is a firmware interface to HWP, setting
this bit effectively tells the firmware that the OS will handle
thermal interrupts natively going forward.
For details on _OSC/_PDC refer to:
http://www.intel.com/content/www/us/en/standards/processor-vendor-specific-acpi-specification.html
To implement the _OSC/_PDC handshake as described, introduce a new
function, acpi_early_processor_osc(), that walks the ACPI
namespace looking for ACPI processor objects and invokes _OSC for
them with bit 12 in the capabilities buffer set and terminates the
namespace walk on the first success.
Also modify intel_thermal_interrupt() to clear HWP status bits in
the HWP_STATUS MSR to acknowledge HWP interrupts (which prevents
them from firing continuously).
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Subject & changelog, function rename ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Implement the stack depot and provide CONFIG_STACKDEPOT. Stack depot
will allow KASAN store allocation/deallocation stack traces for memory
chunks. The stack traces are stored in a hash table and referenced by
handles which reside in the kasan_alloc_meta and kasan_free_meta
structures in the allocated memory chunks.
IRQ stack traces are cut below the IRQ entry point to avoid unnecessary
duplication.
Right now stackdepot support is only enabled in SLAB allocator. Once
KASAN features in SLAB are on par with those in SLUB we can switch SLUB
to stackdepot as well, thus removing the dependency on SLUB stack
bookkeeping, which wastes a lot of memory.
This patch is based on the "mm: kasan: stack depots" patch originally
prepared by Dmitry Chernenkov.
Joonsoo has said that he plans to reuse the stackdepot code for the
mm/page_owner.c debugging facility.
[akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t]
[aryabinin@virtuozzo.com: comment style fixes]
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.
Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>. Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently Xen uses default_cpu_present_to_apicid() which will always
report BAD_APICID for PV guests since x86_bios_cpu_apic_id is initialised
to that value and is never updated.
With commit 1f12e32f4c ("x86/topology: Create logical package id"), this
op is now called by smp_init_package_map() when deciding whether to call
topology_update_package_map() which sets cpu_data(cpu).logical_proc_id.
The latter (as topology_logical_package_id(cpu)) may be used, for example,
by cpu_to_rapl_pmu() as an array index. Since uninitialized
logical_package_id is set to -1, the index will become 64K which is
obviously problematic.
While RAPL code (and any other users of logical_package_id) should be
careful in their assumptions about id's validity, Xen's
cpu_present_to_apicid op should still provide value consistent with its
own xen_apic_read(APIC_ID).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Some visible changes:
A new flag was added to distinguish traces done in NMI context.
Preempt tracer now shows functions where preemption is disabled but
interrupts are still enabled.
Other notes:
Updates were done to function tracing to allow better performance
with perf.
Infrastructure code has been added to allow for a new histogram
feature for recording live trace event histograms that can be
configured by simple user commands. The feature itself was just
finished, but needs a round in linux-next before being pulled.
This only includes some infrastructure changes that will be needed.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJW8/WPAAoJEKKk/i67LK/8wrAH/j2gU9ZfjVxTu8068TBGWRJP
yvvzq0cK5evB3dsVuUmKKRfU52nSv4J1WcFF569X0RulSLylR0dHlcxFJMn4kkgR
bm0AHRrqOf87ub3VimcpG146iVQij37l5A0SRoFbvSPLQx1KUW18v99x41Ji8dv6
oWXRc6/YhdzEE7l0nUsVjmScQ4b2emsems3cxZzXOY+nRJsiim6i+VaDeatdyey1
csLVqtRCs+x62TVtxG3+GhcLdRoPRbnHAGzrKDFIn1SrQaRXCc54wN5d2hWxjgNI
1laOwaj070lnJiWfBLIP/K+lx+VKRx5/O0rKZX35foLUTqJJKSyjAbKXuMCcSAM=
=2h2K
-----END PGP SIGNATURE-----
Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"Nothing major this round. Mostly small clean ups and fixes.
Some visible changes:
- A new flag was added to distinguish traces done in NMI context.
- Preempt tracer now shows functions where preemption is disabled but
interrupts are still enabled.
Other notes:
- Updates were done to function tracing to allow better performance
with perf.
- Infrastructure code has been added to allow for a new histogram
feature for recording live trace event histograms that can be
configured by simple user commands. The feature itself was just
finished, but needs a round in linux-next before being pulled.
This only includes some infrastructure changes that will be needed"
* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
tracing: Record and show NMI state
tracing: Fix trace_printk() to print when not using bprintk()
tracing: Remove redundant reset per-CPU buff in irqsoff tracer
x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
tracing: Fix crash from reading trace_pipe with sendfile
tracing: Have preempt(irqs)off trace preempt disabled functions
tracing: Fix return while holding a lock in register_tracer()
ftrace: Use kasprintf() in ftrace_profile_tracefs()
ftrace: Update dynamic ftrace calls only if necessary
ftrace: Make ftrace_hash_rec_enable return update bool
tracing: Fix typoes in code comment and printk in trace_nop.c
tracing, writeback: Replace cgroup path to cgroup ino
tracing: Use flags instead of bool in trigger structure
tracing: Add an unreg_all() callback to trigger commands
tracing: Add needs_rec flag to event triggers
tracing: Add a per-event-trigger 'paused' field
tracing: Add get_syscall_name()
tracing: Add event record param to trigger_ops.func()
tracing: Make event trigger functions available
tracing: Make ftrace_event_field checking functions available
...
Pull perf fixes from Ingo Molnar:
"This tree contains various perf fixes on the kernel side, plus three
hw/event-enablement late additions:
- Intel Memory Bandwidth Monitoring events and handling
- the AMD Accumulated Power Mechanism reporting facility
- more IOMMU events
... and a final round of perf tooling updates/fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
perf llvm: Use strerror_r instead of the thread unsafe strerror one
perf llvm: Use realpath to canonicalize paths
perf tools: Unexport some methods unused outside strbuf.c
perf probe: No need to use formatting strbuf method
perf help: Use asprintf instead of adhoc equivalents
perf tools: Remove unused perf_pathdup, xstrdup functions
perf tools: Do not include stringify.h from the kernel sources
tools include: Copy linux/stringify.h from the kernel
tools lib traceevent: Remove redundant CPU output
perf tools: Remove needless 'extern' from function prototypes
perf tools: Simplify die() mechanism
perf tools: Remove unused DIE_IF macro
perf script: Remove lots of unused arguments
perf thread: Rename perf_event__preprocess_sample_addr to thread__resolve
perf machine: Rename perf_event__preprocess_sample to machine__resolve
perf tools: Add cpumode to struct perf_sample
perf tests: Forward the perf_sample in the dwarf unwind test
perf tools: Remove misplaced __maybe_unused
perf list: Fix documentation of :ppp
perf bench numa: Fix assertion for nodes bitfield
...
After e76b027 ("x86,vdso: Use LSL unconditionally for vgetcpu")
native_read_tscp() is unused in the kernel. The function can be removed like
native_read_tsc() was.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1458687968-9106-1-git-send-email-prarit@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Merge third patch-bomb from Andrew Morton:
- more ocfs2 changes
- a few hotfixes
- Andy's compat cleanups
- misc fixes to fatfs, ptrace, coredump, cpumask, creds, eventfd,
panic, ipmi, kgdb, profile, kfifo, ubsan, etc.
- many rapidio updates: fixes, new drivers.
- kcov: kernel code coverage feature. Like gcov, but not
"prohibitively expensive".
- extable code consolidation for various archs
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (81 commits)
ia64/extable: use generic search and sort routines
x86/extable: use generic search and sort routines
s390/extable: use generic search and sort routines
alpha/extable: use generic search and sort routines
kernel/...: convert pr_warning to pr_warn
drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings
drivers: dma-coherent: use MEMREMAP_WC for DMA_MEMORY_MAP
memremap: add MEMREMAP_WC flag
memremap: don't modify flags
kernel/signal.c: add compile-time check for __ARCH_SI_PREAMBLE_SIZE
mm/mprotect.c: don't imply PROT_EXEC on non-exec fs
ipc/sem: make semctl setting sempid consistent
ubsan: fix tree-wide -Wmaybe-uninitialized false positives
kfifo: fix sparse complaints
scripts/gdb: account for changes in module data structure
scripts/gdb: add cmdline reader command
scripts/gdb: add version command
kernel: add kcov code coverage
profile: hide unused functions when !CONFIG_PROC_FS
hpwdt: use nmi_panic() when kernel panics in NMI handler
...
* Miscellaneous bugfixes for ARM KVM
* Cleanup of memory barrier and removal of redundant barriers
* x86 fixes: page tracking oops, support for old buggy KVM nested on 4.5
* Support for protection keys in guests
* Lockdep fix
* Another conversion to simple wait queues and raw spinlocks,
backported from PREEMPT_RT
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJW8aaXAAoJEL/70l94x66D7voH/i2ytj6PbuWQQobSKDY38x8F
MHDFJ5UgTFZPPt8cB8YiCl6Tu0C5I2mNOk0rfb+bcpM5C1U9IAnBbbupyUblp6K9
1u+u+al8IlnOsoLzJSUXKDK5H4mEVrUnwVxTpZol5Ph5qQ8FvpbkxboMu3AGevO5
PIUXucK7fP5WXVV3Nh4YnUnBkeYzuuXcqYcV/TjscNQ4NcMofElcgpBxmE498TTk
rvhyuf2chEtY2DsDh3nzeYgxcGLpvE4/l5a+puEoOx4M5CH24wwne9LHAWJz6ofm
H3XNhsCz3jIGmrNqqkGUUya5qSkCsq2ha7n+VDw+fiP1TKy3FtkrBYQrDj+ISuc=
=UtvF
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Paolo Bonzini:
"Second round of KVM changes for 4.6:
- build fixes for PPC KVM
- miscellaneous bugfixes for ARM KVM
- cleanup of memory barrier and removal of redundant barriers
- x86 fixes: page tracking oops, support for old buggy KVM nested on 4.5
- support for protection keys in guests
- lockdep fix
- another conversion to simple wait queues and raw spinlocks,
backported from PREEMPT_RT"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (27 commits)
KVM: page_track: fix access to NULL slot
KVM: PPC: do not compile in vfio.o unconditionally
kvm, rt: change async pagefault code locking for PREEMPT_RT
KVM/PPC: update the comment of memory barrier in the kvmppc_prepare_to_enter()
KVM/x86: update the comment of memory barrier in the vcpu_enter_guest()
KVM: Replace smp_mb() with smp_load_acquire() in the kvm_flush_remote_tlbs()
KVM/x86: Call smp_wmb() before increasing tlbs_dirty
KVM: Replace smp_mb() with smp_mb_after_atomic() in the kvm_make_all_cpus_request()
KVM/x86: Replace smp_mb() with smp_store_mb/release() in the walk_shadow_page_lockless_begin/end()
KVM: Remove redundant smp_mb() in the kvm_mmu_commit_zap_page()
KVM, pkeys: expose CPUID/CR4 to guest
KVM, pkeys: add pkeys support for permission_fault
KVM, pkeys: introduce pkru_mask to cache conditions
KVM, pkeys: save/restore PKRU when guest/host switches
x86: pkey: introduce write_pkru() for KVM
KVM, pkeys: add pkeys support for xsave state
KVM, pkeys: disable pkeys for guests in non-paging mode
KVM: x86: remove magic number with enum cpuid_leafs
KVM: MMU: return page fault error code from permission_fault
KVM: fix spin_lock_init order on x86
...
Replace the arch specific versions of search_extable() and
sort_extable() with calls to the generic ones, which now support
relative exception tables as well.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing). Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system. A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/). However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.
kcov does not aim to collect as much coverage as possible. It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g. scheduler, locking).
Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes. Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch). I've
dropped the second mode for simplicity.
This patch adds the necessary support on kernel side. The complimentary
compiler support was added in gcc revision 231296.
We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:
https://github.com/google/syzkaller/wiki/Found-Bugs
We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation". For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.
Why not gcov. Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat. A
typical coverage can be just a dozen of basic blocks (e.g. an invalid
input). In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M). Cost of
kcov depends only on number of executed basic blocks/edges. On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.
kcov exposes kernel PCs and control flow to user-space which is
insecure. But debugfs should not be mapped as user accessible.
Based on a patch by Quentin Casasnovas.
[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: David Drysdale <drysdale@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
