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Linux kernel
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See Documentation/00-INDEX for a list of what is contained in each file.
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Pull x86/pti updates from Thomas Gleixner:
"A mixed bag of fixes and updates for the ghosts which are hunting us.
The scheduler fixes have been pulled into that branch to avoid
conflicts.
- A set of fixes to address a khread_parkme() race which caused lost
wakeups and loss of state.
- A deadlock fix for stop_machine() solved by moving the wakeups
outside of the stopper_lock held region.
- A set of Spectre V1 array access restrictions. The possible
problematic spots were discuvered by Dan Carpenters new checks in
smatch.
- Removal of an unused file which was forgotten when the rest of that
functionality was removed"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vdso: Remove unused file
perf/x86/cstate: Fix possible Spectre-v1 indexing for pkg_msr
perf/x86/msr: Fix possible Spectre-v1 indexing in the MSR driver
perf/x86: Fix possible Spectre-v1 indexing for x86_pmu::event_map()
perf/x86: Fix possible Spectre-v1 indexing for hw_perf_event cache_*
perf/core: Fix possible Spectre-v1 indexing for ->aux_pages[]
sched/autogroup: Fix possible Spectre-v1 indexing for sched_prio_to_weight[]
sched/core: Fix possible Spectre-v1 indexing for sched_prio_to_weight[]
sched/core: Introduce set_special_state()
kthread, sched/wait: Fix kthread_parkme() completion issue
kthread, sched/wait: Fix kthread_parkme() wait-loop
sched/fair: Fix the update of blocked load when newly idle
stop_machine, sched: Fix migrate_swap() vs. active_balance() deadlock
Pull scheduler fix from Thomas Gleixner:
"Revert the new NUMA aware placement approach which turned out to
create more problems than it solved"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "sched/numa: Delay retrying placement for automatic NUMA balance after wake_affine()"
commit da861e18eccc ("x86, vdso: Get rid of the fake section mechanism")
left this file behind; nothing is using it anymore.
Signed-off-by: Jann Horn <jannh@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: luto@amacapital.net
Link: http://lkml.kernel.org/r/20180504175935.104085-1-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf tooling fixes from Thomas Gleixner:
"Another small set of perf tooling fixes and updates:
- Revert "perf pmu: Fix pmu events parsing rule", as it broke Intel
PT event description parsing (Arnaldo Carvalho de Melo)
- Sync x86's cpufeatures.h and kvm UAPI headers with the kernel
sources, suppressing the ABI drift warnings (Arnaldo Carvalho de
Melo)
- Remove duplicated entry for westmereep-dp in Intel's mapfile.csv
(William Cohen)
- Fix typo in 'perf bench numa' options description (Yisheng Xie)"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "perf pmu: Fix pmu events parsing rule"
tools headers kvm: Sync ARM UAPI headers with the kernel sources
tools headers kvm: Sync uapi/linux/kvm.h with the kernel sources
tools headers: Sync x86 cpufeatures.h with the kernel sources
perf vendor events intel: Remove duplicated entry for westmereep-dp in mapfile.csv
perf bench numa: Fix typo in options
This reverts commit 7347fc87dfe6b7315e74310ee1243dc222c68086.
Srikar Dronamra pointed out that while the commit in question did show
a performance improvement on ppc64, it did so at the cost of disabling
active CPU migration by automatic NUMA balancing which was not the intent.
The issue was that a serious flaw in the logic failed to ever active balance
if SD_WAKE_AFFINE was disabled on scheduler domains. Even when it's enabled,
the logic is still bizarre and against the original intent.
Investigation showed that fixing the patch in either the way he suggested,
using the correct comparison for jiffies values or introducing a new
numa_migrate_deferred variable in task_struct all perform similarly to a
revert with a mix of gains and losses depending on the workload, machine
and socket count.
The original intent of the commit was to handle a problem whereby
wake_affine, idle balancing and automatic NUMA balancing disagree on the
appropriate placement for a task. This was particularly true for cases where
a single task was a massive waker of tasks but where wake_wide logic did
not apply. This was particularly noticeable when a futex (a barrier) woke
all worker threads and tried pulling the wakees to the waker nodes. In that
specific case, it could be handled by tuning MPI or openMP appropriately,
but the behavior is not illogical and was worth attempting to fix. However,
the approach was wrong. Given that we're at rc4 and a fix is not obvious,
it's better to play safe, revert this commit and retry later.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: efault@gmx.de
Cc: ggherdovich@suse.cz
Cc: hpa@zytor.com
Cc: matt@codeblueprint.co.uk
Cc: mpe@ellerman.id.au
Link: http://lkml.kernel.org/r/20180509163115.6fnnyeg4vdm2ct4v@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
> arch/x86/events/intel/cstate.c:307 cstate_pmu_event_init() warn: potential spectre issue 'pkg_msr' (local cap)
Userspace controls @attr, sanitize cfg (attr->config) before using it
to index an array.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull dma-mapping fix from Christoph Hellwig:
"Just one little fix from Jean to avoid a harmless but very annoying
warning, especially for the drm code"
* tag 'dma-mapping-4.17-5' of git://git.infradead.org/users/hch/dma-mapping:
swiotlb: silent unwanted warning "buffer is full"
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
. Revert "perf pmu: Fix pmu events parsing rule", as it broke Intel PT
event description parsing (Arnaldo Carvalho de Melo)
. Sync x86's cpufeatures.h and kvm UAPI headers with the kernel sources,
suppressing the ABI drift warnings (Arnaldo Carvalho de Melo)
- Remove duplicated entry for westmereep-dp in Intel's mapfile.csv (William Cohen)
- Fix typo in 'perf bench numa' options description (Yisheng Xie)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull device mapper fixes from Mike Snitzer:
- a stable fix for DM integrity to use kvfree
- fix for a 4.17-rc1 change to dm-bufio's buffer alignment
- fixes for a few sparse warnings
- remove VLA usage in DM mirror target
- improve DM thinp Documentation for the "read_only" feature
* tag 'for-4.17/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm thin: update Documentation to clarify when "read_only" is valid
dm mirror: remove VLA usage
dm: fix some sparse warnings and whitespace in dax methods
dm cache background tracker: fix sparse warning
dm bufio: fix buffer alignment
dm integrity: use kvfree for kvmalloc'd memory
> arch/x86/events/msr.c:178 msr_event_init() warn: potential spectre issue 'msr' (local cap)
Userspace controls @attr, sanitize cfg (attr->config) before using it
to index an array.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull cifs fixes from Steve French:
"Some small SMB3 fixes for 4.17-rc5, some for stable"
* tag '4.17-rc4-SMB3-Fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb3: directory sync should not return an error
cifs: smb2ops: Fix listxattr() when there are no EAs
cifs: smbd: Enable signing with smbdirect
cifs: Allocate validate negotiation request through kmalloc
If DMA_ATTR_NO_WARN is passed to swiotlb_alloc_buffer(), it should be
passed further down to swiotlb_tbl_map_single(). Otherwise we escape
half of the warnings but still log the other half.
This is one of the multiple causes of spurious warnings reported at:
https://bugs.freedesktop.org/show_bug.cgi?id=104082
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 0176adb00406 ("swiotlb: refactor coherent buffer allocation")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Michel Dänzer <michel@daenzer.net>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: stable@vger.kernel.org # v4.16
As reported by Adrian Hunter, this breaks intel_pt event parsing:
# perf record -e intel_pt//u uname
event syntax error: 'intel_pt//u'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-e, --event <event> event selector. use 'perf list' to list available events
#
This reverts commit 9a4a931ce847f4aaa12edf11b2e050e18bf45910.
Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-ye1o2mji7x68xotiot1tn1gp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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