This warning:
WARNING: CPU: 0 PID: 3331 at arch/x86/entry/common.c:45 enter_from_user_mode+0x32/0x50
CPU: 0 PID: 3331 Comm: ldt_gdt_64 Not tainted 4.8.0-rc7+ #13
Call Trace:
dump_stack+0x99/0xd0
__warn+0xd1/0xf0
warn_slowpath_null+0x1d/0x20
enter_from_user_mode+0x32/0x50
error_entry+0x6d/0xc0
? general_protection+0x12/0x30
? native_load_gs_index+0xd/0x20
? do_set_thread_area+0x19c/0x1f0
SyS_set_thread_area+0x24/0x30
do_int80_syscall_32+0x7c/0x220
entry_INT80_compat+0x38/0x50
... can be reproduced by running the GS testcase of the ldt_gdt test unit in
the x86 selftests.
do_int80_syscall_32() will call enter_form_user_mode() to convert context
tracking state from user state to kernel state. The load_gs_index() call
can fail with user gsbase, gsbase will be fixed up and proceed if this
happen.
However, enter_from_user_mode() will be called again in the fixed up path
though it is context tracking kernel state currently.
This patch fixes it by just fixing up gsbase and telling lockdep that IRQs
are off once load_gs_index() failed with user gsbase.
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-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>
Link: http://lkml.kernel.org/r/1475197266-3440-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf fixes from Thomas Gleixner:
"Three fixlets for perf:
- add a missing NULL pointer check in the intel BTS driver
- make BTS an exclusive PMU because BTS can only handle one event at
a time
- ensure that exclusive events are limited to one PMU so that several
exclusive events can be scheduled on different PMU instances"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Limit matching exclusive events to one PMU
perf/x86/intel/bts: Make it an exclusive PMU
perf/x86/intel/bts: Make sure debug store is valid
Since commit 4d4c474124 ("perf/x86/intel/bts: Fix BTS PMI detection")
my box goes boom on boot:
| .... node #0, CPUs: #1#2#3#4#5#6#7
| BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
| IP: [<ffffffff8100c463>] intel_bts_interrupt+0x43/0x130
| Call Trace:
| <NMI> d [<ffffffff8100b341>] intel_pmu_handle_irq+0x51/0x4b0
| [<ffffffff81004d47>] perf_event_nmi_handler+0x27/0x40
This happens because the code introduced in this commit dereferences the
debug store pointer unconditionally. The debug store is not guaranteed to
be available, so a NULL pointer check as on other places is required.
Fixes: 4d4c474124 ("perf/x86/intel/bts: Fix BTS PMI detection")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: vince@deater.net
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/20160920131220.xg5pbdjtznszuyzb@breakpoint.cc
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There's a mixture of signed 32-bit and unsigned 32-bit and 64-bit data
types used for keeping track of how many pages have been mapped.
This leads to hangs during boot when mapping large numbers of pages
(multiple terabytes, as reported by Waiman) because those values are
interpreted as being negative.
commit 742563777e ("x86/mm/pat: Avoid truncation when converting
cpa->numpages to address") fixed one of those bugs, but there is
another lurking in __change_page_attr_set_clr().
Additionally, the return value type for the populate_*() functions can
return negative values when a large number of pages have been mapped,
triggering the error paths even though no error occurred.
Consistently use 64-bit types on 64-bit platforms when counting pages.
Even in the signed case this gives us room for regions 8PiB
(pebibytes) in size whilst still allowing the usual negative value
error checking idiom.
Reported-by: Waiman Long <waiman.long@hpe.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
CC: Theodore Ts'o <tytso@mit.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Scott J Norton <scott.norton@hpe.com>
Cc: Douglas Hatch <doug.hatch@hpe.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Pull perf fixes from Thomas Gleixner:
"A couple of small fixes to x86 perf drivers:
- Measure L2 for HW_CACHE* events on AMD
- Fix the address filter handling in the intel/pt driver
- Handle the BTS disabling at the proper place"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd: Make HW_CACHE_REFERENCES and HW_CACHE_MISSES measure L2
perf/x86/intel/pt: Do validate the size of a kernel address filter
perf/x86/intel/pt: Fix kernel address filter's offset validation
perf/x86/intel/pt: Fix an off-by-one in address filter configuration
perf/x86/intel: Don't disable "intel_bts" around "intel" event batching
While the Intel PMU monitors the LLC when perf enables the
HW_CACHE_REFERENCES and HW_CACHE_MISSES events, these events monitor
L1 instruction cache fetches (0x0080) and instruction cache misses
(0x0081) on the AMD PMU.
This is extremely confusing when monitoring the same workload across
Intel and AMD machines, since parameters like,
$ perf stat -e cache-references,cache-misses
measure completely different things.
Instead, make the AMD PMU measure instruction/data cache and TLB fill
requests to the L2 and instruction/data cache and TLB misses in the L2
when HW_CACHE_REFERENCES and HW_CACHE_MISSES are enabled,
respectively. That way the events measure unified caches on both
platforms.
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1472044328-21302-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull kvm fix from Paolo Bonzini:
"One fix for an x86 regression in VM migration, mostly visible with
Windows because it uses RTC periodic interrupts"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: x86: correctly reset dest_map->vector when restoring LAPIC state
get_user_ex(x, ptr) should zero x on failure. It's not a lot of a leak
(at most we are leaking uninitialized 64bit value off the kernel stack,
and in a fairly constrained situation, at that), but the fix is trivial,
so...
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[ This sat in different branch from the uaccess fixes since mid-August ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When userspace sends KVM_SET_LAPIC, KVM schedules a check between
the vCPU's IRR and ISR and the IOAPIC redirection table, in order
to re-establish the IOAPIC's dest_map (the list of CPUs servicing
the real-time clock interrupt with the corresponding vectors).
However, __rtc_irq_eoi_tracking_restore_one was forgetting to
set dest_map->vectors. Because of this, the IOAPIC did not process
the real-time clock interrupt EOI, ioapic->rtc_status.pending_eoi
got stuck at a non-zero value, and further RTC interrupts were
reported to userspace as coalesced.
Fixes: 9e4aabe2bb
Fixes: 4d99ba898d
Cc: stable@vger.kernel.org
Cc: Joerg Roedel <jroedel@suse.de>
Cc: David Gilbert <dgilbert@redhat.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull PCI fixes from Bjorn Helgaas:
"Here are two changes for v4.8. The first fixes a "[Firmware Bug]: reg
0x10: invalid BAR (can't size)" warning on Haswell, and the second
fixes a problem in some new runtime suspend functionality we merged
for v4.8. Summary:
Enumeration:
Mark Haswell Power Control Unit as having non-compliant BARs (Bjorn Helgaas)
Power management:
Fix bridge_d3 update on device removal (Lukas Wunner)"
* tag 'pci-v4.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: Fix bridge_d3 update on device removal
PCI: Mark Haswell Power Control Unit as having non-compliant BARs
Pull x86 fixes from Ingo Molnar:
"Three fixes:
- AMD microcode loading fix with randomization
- an lguest tooling fix
- and an APIC enumeration boundary condition fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Fix num_processors value in case of failure
tools/lguest: Don't bork the terminal in case of wrong args
x86/microcode/AMD: Fix load of builtin microcode with randomized memory
Pull perf fixes from Ingo Molnar:
"This contains:
- a set of fixes found by directed-random perf fuzzing efforts by
Vince Weaver, Alexander Shishkin and Peter Zijlstra
- a cqm driver crash fix
- an AMD uncore driver use after free fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Fix PEBSv3 record drain
perf/x86/intel/bts: Kill a silly warning
perf/x86/intel/bts: Fix BTS PMI detection
perf/x86/intel/bts: Fix confused ordering of PMU callbacks
perf/core: Fix aux_mmap_count vs aux_refcount order
perf/core: Fix a race between mmap_close() and set_output() of AUX events
perf/x86/amd/uncore: Prevent use after free
perf/x86/intel/cqm: Check cqm/mbm enabled state in event init
perf/core: Remove WARN from perf_event_read()
Pull EFI fixes from Ingo Molnar:
"This contains a Xen fix, an arm64 fix and a race condition /
robustization set of fixes related to ExitBootServices() usage and
boundary conditions"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Use efi_exit_boot_services()
efi/libstub: Use efi_exit_boot_services() in FDT
efi/libstub: Introduce ExitBootServices helper
efi/libstub: Allocate headspace in efi_get_memory_map()
efi: Fix handling error value in fdt_find_uefi_params
efi: Make for_each_efi_memory_desc_in_map() cope with running on Xen
Pull libnvdimm fixes from Dan Williams:
"nvdimm fixes for v4.8, two of them are tagged for -stable:
- Fix devm_memremap_pages() to use track_pfn_insert(). Otherwise,
DAX pmd mappings end up with an uncached pgprot, and unusable
performance for the device-dax interface. The device-dax interface
appeared in 4.7 so this is tagged for -stable.
- Fix a couple VM_BUG_ON() checks in the show_smaps() path to
understand DAX pmd entries. This fix is tagged for -stable.
- Fix a mis-merge of the nfit machine-check handler to flip the
polarity of an if() to match the final version of the patch that
Vishal sent for 4.8-rc1. Without this the nfit machine check
handler never detects / inserts new 'badblocks' entries which
applications use to identify lost portions of files.
- For test purposes, fix the nvdimm_clear_poison() path to operate on
legacy / simulated nvdimm memory ranges. Without this fix a test
can set badblocks, but never clear them on these ranges.
- Fix the range checking done by dax_dev_pmd_fault(). This is not
tagged for -stable since this problem is mitigated by specifying
aligned resources at device-dax setup time.
These patches have appeared in a next release over the past week. The
recent rebase you can see in the timestamps was to drop an invalid fix
as identified by the updated device-dax unit tests [1]. The -mm
touches have an ack from Andrew"
[1]: "[ndctl PATCH 0/3] device-dax test for recent kernel bugs"
https://lists.01.org/pipermail/linux-nvdimm/2016-September/006855.html
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm: allow legacy (e820) pmem region to clear bad blocks
nfit, mce: Fix SPA matching logic in MCE handler
mm: fix cache mode of dax pmd mappings
mm: fix show_smap() for zone_device-pmd ranges
dax: fix mapping size check
track_pfn_insert() in vmf_insert_pfn_pmd() is marking dax mappings as
uncacheable rendering them impractical for application usage. DAX-pte
mappings are cached and the goal of establishing DAX-pmd mappings is to
attain more performance, not dramatically less (3 orders of magnitude).
track_pfn_insert() relies on a previous call to reserve_memtype() to
establish the expected page_cache_mode for the range. While memremap()
arranges for reserve_memtype() to be called, devm_memremap_pages() does
not. So, teach track_pfn_insert() and untrack_pfn() how to handle
tracking without a vma, and arrange for devm_memremap_pages() to
establish the write-back-cache reservation in the memtype tree.
Cc: <stable@vger.kernel.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Reported-by: Kai Zhang <kai.ka.zhang@oracle.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The resent conversion of the cpu hotplug support in the uncore driver
introduced a regression due to the way the callbacks are invoked at
initialization time.
The old code called the prepare/starting/online function on each online cpu
as a block. The new code registers the hotplug callbacks in the core for
each state. The core invokes the callbacks at each registration on all
online cpus.
The code implicitely relied on the prepare/starting/online callbacks being
called as combo on a particular cpu, which was not obvious and completely
undocumented.
The resulting subtle wreckage happens due to the way how the uncore code
manages shared data structures for cpus which share an uncore resource in
hardware. The sharing is determined in the cpu starting callback, but the
prepare callback allocates per cpu data for the upcoming cpu because
potential sharing is unknown at this point. If the starting callback finds
a online cpu which shares the hardware resource it takes a refcount on the
percpu data of that cpu and puts the own data structure into a
'free_at_online' pointer of that shared data structure. The online callback
frees that.
With the old model this worked because in a starting callback only one non
unused structure (the one of the starting cpu) was available. The new code
allocates the data structures for all cpus when the prepare callback is
registered.
Now the starting function iterates through all online cpus and looks for a
data structure (skipping its own) which has a matching hardware id. The id
member of the data structure is initialized to 0, but the hardware id can
be 0 as well. The resulting wreckage is:
CPU0 finds a matching id on CPU1, takes a refcount on CPU1 data and puts
its own data structure into CPU1s data structure to be freed.
CPU1 skips CPU0 because the data structure is its allegedly unsued own.
It finds a matching id on CPU2, takes a refcount on CPU1 data and puts
its own data structure into CPU2s data structure to be freed.
....
Now the online callbacks are invoked.
CPU0 has a pointer to CPU1s data and frees the original CPU0 data. So
far so good.
CPU1 has a pointer to CPU2s data and frees the original CPU1 data, which
is still referenced by CPU0 ---> Booom
So there are two issues to be solved here:
1) The id field must be initialized at allocation time to a value which
cannot be a valid hardware id, i.e. -1
This prevents the above scenario, but now CPU1 and CPU2 both stick their
own data structure into the free_at_online pointer of CPU0. So we leak
CPU1s data structure.
2) Fix the memory leak described in #1
Instead of having a single pointer, use a hlist to enqueue the
superflous data structures which are then freed by the first cpu
invoking the online callback.
Ideally we should know the sharing _before_ invoking the prepare callback,
but that's way beyond the scope of this bug fix.
[ tglx: Rewrote changelog ]
Fixes: 96b2bd3866 ("perf/x86/amd/uncore: Convert to hotplug state machine")
Reported-and-tested-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20160909160822.lowgmkdwms2dheyv@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When booting a kvm guest on AMD with the latest kernel the following
messages are displayed in the boot log:
tsc: Unable to calibrate against PIT
tsc: HPET/PMTIMER calibration failed
aa297292d7 ("x86/tsc: Enumerate SKL cpu_khz and tsc_khz via CPUID")
introduced a change to account for a difference in cpu and tsc frequencies for
Intel SKL processors. Before this change the native tsc set
x86_platform.calibrate_tsc to native_calibrate_tsc() which is a hardware
calibration of the tsc, and in tsc_init() executed
tsc_khz = x86_platform.calibrate_tsc();
cpu_khz = tsc_khz;
The kvm code changed x86_platform.calibrate_tsc to kvm_get_tsc_khz() and
executed the same tsc_init() function. This meant that KVM guests did not
execute the native hardware calibration function.
After aa297292d7, there are separate native calibrations for cpu_khz and
tsc_khz. The code sets x86_platform.calibrate_tsc to native_calibrate_tsc()
which is now an Intel specific calibration function, and
x86_platform.calibrate_cpu to native_calibrate_cpu() which is the "old"
native_calibrate_tsc() function (ie, the native hardware calibration
function).
tsc_init() now does
cpu_khz = x86_platform.calibrate_cpu();
tsc_khz = x86_platform.calibrate_tsc();
if (tsc_khz == 0)
tsc_khz = cpu_khz;
else if (abs(cpu_khz - tsc_khz) * 10 > tsc_khz)
cpu_khz = tsc_khz;
The kvm code should not call the hardware initialization in
native_calibrate_cpu(), as it isn't applicable for kvm and it didn't do that
prior to aa297292d7.
This patch resolves this issue by setting x86_platform.calibrate_cpu to
kvm_get_tsc_khz().
v2: I had originally set x86_platform.calibrate_cpu to
cpu_khz_from_cpuid(), however, pbonzini pointed out that the CPUID leaf
in that function is not available in KVM. I have changed the function
pointer to kvm_get_tsc_khz().
Fixes: aa297292d7 ("x86/tsc: Enumerate SKL cpu_khz and tsc_khz via CPUID")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Len Brown <len.brown@intel.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Christopher S. Hall" <christopher.s.hall@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull seccomp fixes from Kees Cook:
"Fix UM seccomp vs ptrace, after reordering landed"
* tag 'seccomp-v4.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
seccomp: Remove 2-phase API documentation
um/ptrace: Fix the syscall number update after a ptrace
um/ptrace: Fix the syscall_trace_leave call
Update the syscall number after each PTRACE_SETREGS on ORIG_*AX.
This is needed to get the potentially altered syscall number in the
seccomp filters after RET_TRACE.
This fix four seccomp_bpf tests:
> [ RUN ] TRACE_syscall.skip_after_RET_TRACE
> seccomp_bpf.c:1560:TRACE_syscall.skip_after_RET_TRACE:Expected -1 (18446744073709551615) == syscall(39) (26)
> seccomp_bpf.c:1561:TRACE_syscall.skip_after_RET_TRACE:Expected 1 (1) == (*__errno_location ()) (22)
> [ FAIL ] TRACE_syscall.skip_after_RET_TRACE
> [ RUN ] TRACE_syscall.kill_after_RET_TRACE
> TRACE_syscall.kill_after_RET_TRACE: Test exited normally instead of by signal (code: 1)
> [ FAIL ] TRACE_syscall.kill_after_RET_TRACE
> [ RUN ] TRACE_syscall.skip_after_ptrace
> seccomp_bpf.c:1622:TRACE_syscall.skip_after_ptrace:Expected -1 (18446744073709551615) == syscall(39) (26)
> seccomp_bpf.c:1623:TRACE_syscall.skip_after_ptrace:Expected 1 (1) == (*__errno_location ()) (22)
> [ FAIL ] TRACE_syscall.skip_after_ptrace
> [ RUN ] TRACE_syscall.kill_after_ptrace
> TRACE_syscall.kill_after_ptrace: Test exited normally instead of by signal (code: 1)
> [ FAIL ] TRACE_syscall.kill_after_ptrace
Fixes: 26703c636c ("um/ptrace: run seccomp after ptrace")
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: James Morris <jmorris@namei.org>
Cc: user-mode-linux-devel@lists.sourceforge.net
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
As already done with __copy_*_user(), mark copy_*_user() as __always_inline.
Without this, the checks for things like __builtin_const_p() won't work
consistently in either hardened usercopy nor the recent adjustments for
detecting usercopy overflows at compile time.
The change in kernel text size is detectable, but very small:
text data bss dec hex filename
12118735 5768608 14229504 32116847 1ea106f vmlinux.before
12120207 5768608 14229504 32118319 1ea162f vmlinux.after
Signed-off-by: Kees Cook <keescook@chromium.org>
Yanqiu Zhang reported kernel panic when using mbm event
on system where CQM is detected but without mbm event
support, like with perf:
# perf stat -e 'intel_cqm/event=3/' -a
BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
IP: [<ffffffff8100d64c>] update_sample+0xbc/0xe0
...
<IRQ>
[<ffffffff8100d688>] __intel_mbm_event_init+0x18/0x20
[<ffffffff81113d6b>] flush_smp_call_function_queue+0x7b/0x160
[<ffffffff81114853>] generic_smp_call_function_single_interrupt+0x13/0x60
[<ffffffff81052017>] smp_call_function_interrupt+0x27/0x40
[<ffffffff816fb06c>] call_function_interrupt+0x8c/0xa0
...
The reason is that we currently allow to init mbm event
even if mbm support is not detected. Adding checks for
both cqm and mbm events and support into cqm's event_init.
Fixes: 33c3cc7acf ("perf/x86/mbm: Add Intel Memory B/W Monitoring enumeration and init")
Reported-by: Yanqiu Zhang <yanqzhan@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1473089407-21857-1-git-send-email-jolsa@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
TSC_OFFSET will be adjusted if discovers TSC backward during vCPU load.
The preemption timer, which relies on the guest tsc to reprogram its
preemption timer value, is also reprogrammed if vCPU is scheded in to
a different pCPU. However, the current implementation reprogram preemption
timer before TSC_OFFSET is adjusted to the right value, resulting in the
preemption timer firing prematurely.
This patch fix it by adjusting TSC_OFFSET before reprogramming preemption
timer if TSC backward.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krċmář <rkrcmar@redhat.com>
Cc: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The eboot code directly calls ExitBootServices. This is inadvisable as the
UEFI spec details a complex set of errors, race conditions, and API
interactions that the caller of ExitBootServices must get correct. The
eboot code attempts allocations after calling ExitBootSerives which is
not permitted per the spec. Call the efi_exit_boot_services() helper
intead, which handles the allocation scenario properly.
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
efi_get_memory_map() allocates a buffer to store the memory map that it
retrieves. This buffer may need to be reused by the client after
ExitBootServices() is called, at which point allocations are not longer
permitted. To support this usecase, provide the allocated buffer size back
to the client, and allocate some additional headroom to account for any
reasonable growth in the map that is likely to happen between the call to
efi_get_memory_map() and the client reusing the buffer.
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Pull x86 fix from Thomas Gleixner:
"A single fix for an AMD erratum so machines without a BIOS fix work"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/AMD: Apply erratum 665 on machines without a BIOS fix
Łukasz Daniluk reported that on a RHEL kernel that his machine would lock up
after enabling function tracer. I asked him to bisect the functions within
available_filter_functions, which he did and it came down to three:
_paravirt_nop(), _paravirt_ident_32() and _paravirt_ident_64()
It was found that this is only an issue when noreplace-paravirt is added
to the kernel command line.
This means that those functions are most likely called within critical
sections of the funtion tracer, and must not be traced.
In newer kenels _paravirt_nop() is defined within gcc asm(), and is no
longer an issue. But both _paravirt_ident_{32,64}() causes the
following splat when they are traced:
mm/pgtable-generic.c:33: bad pmd ffff8800d2435150(0000000001d00054)
mm/pgtable-generic.c:33: bad pmd ffff8800d3624190(0000000001d00070)
mm/pgtable-generic.c:33: bad pmd ffff8800d36a5110(0000000001d00054)
mm/pgtable-generic.c:33: bad pmd ffff880118eb1450(0000000001d00054)
NMI watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [systemd-journal:469]
Modules linked in: e1000e
CPU: 2 PID: 469 Comm: systemd-journal Not tainted 4.6.0-rc4-test+ #513
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012
task: ffff880118f740c0 ti: ffff8800d4aec000 task.ti: ffff8800d4aec000
RIP: 0010:[<ffffffff81134148>] [<ffffffff81134148>] queued_spin_lock_slowpath+0x118/0x1a0
RSP: 0018:ffff8800d4aefb90 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88011eb16d40
RDX: ffffffff82485760 RSI: 000000001f288820 RDI: ffffea0000008030
RBP: ffff8800d4aefb90 R08: 00000000000c0000 R09: 0000000000000000
R10: ffffffff821c8e0e R11: 0000000000000000 R12: ffff880000200fb8
R13: 00007f7a4e3f7000 R14: ffffea000303f600 R15: ffff8800d4b562e0
FS: 00007f7a4e3d7840(0000) GS:ffff88011eb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7a4e3f7000 CR3: 00000000d3e71000 CR4: 00000000001406e0
Call Trace:
_raw_spin_lock+0x27/0x30
handle_pte_fault+0x13db/0x16b0
handle_mm_fault+0x312/0x670
__do_page_fault+0x1b1/0x4e0
do_page_fault+0x22/0x30
page_fault+0x28/0x30
__vfs_read+0x28/0xe0
vfs_read+0x86/0x130
SyS_read+0x46/0xa0
entry_SYSCALL_64_fastpath+0x1e/0xa8
Code: 12 48 c1 ea 0c 83 e8 01 83 e2 30 48 98 48 81 c2 40 6d 01 00 48 03 14 c5 80 6a 5d 82 48 89 0a 8b 41 08 85 c0 75 09 f3 90 8b 41 08 <85> c0 74 f7 4c 8b 09 4d 85 c9 74 08 41 0f 18 09 eb 02 f3 90 8b
Reported-by: Łukasz Daniluk <lukasz.daniluk@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Using "make tinyconfig" produces a couple of annoying warnings that show
up for build test machines all the time:
.config:966:warning: override: NOHIGHMEM changes choice state
.config:965:warning: override: SLOB changes choice state
.config:963:warning: override: KERNEL_XZ changes choice state
.config:962:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state
.config:933:warning: override: SLOB changes choice state
.config:930:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state
.config:870:warning: override: SLOB changes choice state
.config:868:warning: override: KERNEL_XZ changes choice state
.config:867:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state
I've made a previous attempt at fixing them and we discussed a number of
alternatives.
I tried changing the Makefile to use "merge_config.sh -n
$(fragment-list)" but couldn't get that to work properly.
This is yet another approach, based on the observation that we do want
to see a warning for conflicting 'choice' options, and that we can
simply make them non-conflicting by listing all other options as
disabled. This is a trivial patch that we can apply independent of
plans for other changes.
Link: http://lkml.kernel.org/r/20160829214952.1334674-2-arnd@arndb.de
Link: https://storage.kernelci.org/mainline/v4.7-rc6/x86-tinyconfig/build.loghttps://patchwork.kernel.org/patch/9212749/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are three usercopy warnings which are currently being silenced for
gcc 4.6 and newer:
1) "copy_from_user() buffer size is too small" compile warning/error
This is a static warning which happens when object size and copy size
are both const, and copy size > object size. I didn't see any false
positives for this one. So the function warning attribute seems to
be working fine here.
Note this scenario is always a bug and so I think it should be
changed to *always* be an error, regardless of
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS.
2) "copy_from_user() buffer size is not provably correct" compile warning
This is another static warning which happens when I enable
__compiletime_object_size() for new compilers (and
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS). It happens when object size
is const, but copy size is *not*. In this case there's no way to
compare the two at build time, so it gives the warning. (Note the
warning is a byproduct of the fact that gcc has no way of knowing
whether the overflow function will be called, so the call isn't dead
code and the warning attribute is activated.)
So this warning seems to only indicate "this is an unusual pattern,
maybe you should check it out" rather than "this is a bug".
I get 102(!) of these warnings with allyesconfig and the
__compiletime_object_size() gcc check removed. I don't know if there
are any real bugs hiding in there, but from looking at a small
sample, I didn't see any. According to Kees, it does sometimes find
real bugs. But the false positive rate seems high.
3) "Buffer overflow detected" runtime warning
This is a runtime warning where object size is const, and copy size >
object size.
All three warnings (both static and runtime) were completely disabled
for gcc 4.6 with the following commit:
2fb0815c9e ("gcc4: disable __compiletime_object_size for GCC 4.6+")
That commit mistakenly assumed that the false positives were caused by a
gcc bug in __compiletime_object_size(). But in fact,
__compiletime_object_size() seems to be working fine. The false
positives were instead triggered by #2 above. (Though I don't have an
explanation for why the warnings supposedly only started showing up in
gcc 4.6.)
So remove warning #2 to get rid of all the false positives, and re-enable
warnings #1 and #3 by reverting the above commit.
Furthermore, since #1 is a real bug which is detected at compile time,
upgrade it to always be an error.
Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer
needed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fix from Thomas Gleixner:
"A single bugfix to prevent irq remapping when the ioapic is disabled"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Do not init irq remapping if ioapic is disabled
Pull KVM fixes from Paolo Bonzini:
"ARM:
- fixes for ITS init issues, error handling, IRQ leakage, race
conditions
- an erratum workaround for timers
- some removal of misleading use of errors and comments
- a fix for GICv3 on 32-bit guests
MIPS:
- fix for where the guest could wrongly map the first page of
physical memory
x86:
- nested virtualization fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
MIPS: KVM: Check for pfn noslot case
kvm: nVMX: fix nested tsc scaling
KVM: nVMX: postpone VMCS changes on MSR_IA32_APICBASE write
KVM: nVMX: fix msr bitmaps to prevent L2 from accessing L0 x2APIC
arm64: KVM: report configured SRE value to 32-bit world
arm64: KVM: remove misleading comment on pmu status
KVM: arm/arm64: timer: Workaround misconfigured timer interrupt
arm64: Document workaround for Cortex-A72 erratum #853709
KVM: arm/arm64: Change misleading use of is_error_pfn
KVM: arm64: ITS: avoid re-mapping LPIs
KVM: arm64: check for ITS device on MSI injection
KVM: arm64: ITS: move ITS registration into first VCPU run
KVM: arm64: vgic-its: Make updates to propbaser/pendbaser atomic
KVM: arm64: vgic-its: Plug race in vgic_put_irq
KVM: arm64: vgic-its: Handle errors from vgic_add_lpi
KVM: arm64: ITS: return 1 on successful MSI injection
