Commit:

  b5179ac7 ("sched/fair: Prepare to fix fairness problems on migration")

... introduced a bug: Mike Galbraith found that it introduced a
performance regression, while Paul E. McKenney reported lost
wakeups and bisected it to this commit.

The reason is that I mis-read ttwu_queue() such that I assumed any
wakeup that got a remote queue must have had the task migrated.

Since this is not so; we need to transfer this information between
queueing the wakeup and actually doing the wakeup. Use a new
task_struct::sched_flag for this, we already write to
sched_contributes_to_load in the wakeup path so this is a hot and
modified cacheline.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Tested-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Hunter <ahh@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Segall <bsegall@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Turner <pjt@google.com>
Cc: Pavan Kondeti <pkondeti@codeaurora.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: byungchul.park@lge.com
Fixes: b5179ac7 ("sched/fair: Prepare to fix fairness problems on migration")
Link: http://lkml.kernel.org/r/20160523091907.GD15728@worktop.ger.corp.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Vikram reported that his ARM64 compiler managed to 'optimize' away the
preempt_count manipulations in code like:

	preempt_enable_no_resched();
	put_user();
	preempt_disable();

Irrespective of that fact that that is horrible code that should be
fixed for many reasons, it does highlight a deficiency in the generic
preempt_count manipulators. As it is never right to combine/elide
preempt_count manipulations like this.

Therefore sprinkle some volatile in the two generic accessors to
ensure the compiler is aware of the fact that the preempt_count is
observed outside of the regular program-order view and thus cannot be
optimized away like this.

x86; the only arch not using the generic code is not affected as we
do all this in asm in order to use the segment base per-cpu stuff.
Reported-by: Vikram Mulukutla <markivx@codeaurora.org>
Tested-by: Vikram Mulukutla <markivx@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a7878709 ("sched, arch: Create asm/preempt.h")
Link: http://lkml.kernel.org/r/20160516131751.GH3205@twins.programming.kicks-ass.netSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull x86 platform updates from Ingo Molnar:
 "The main change is the addition of SGI/UV4 support"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  x86/platform/UV: Fix incorrect nodes and pnodes for cpuless and memoryless nodes
  x86/platform/UV: Remove Obsolete GRU MMR address translation
  x86/platform/UV: Update physical address conversions for UV4
  x86/platform/UV: Build GAM reference tables
  x86/platform/UV: Support UV4 socket address changes
  x86/platform/UV: Add obtaining GAM Range Table from UV BIOS
  x86/platform/UV: Add UV4 addressing discovery function
  x86/platform/UV: Fold blade info into per node hub info structs
  x86/platform/UV: Allocate common per node hub info structs on local node
  x86/platform/UV: Move blade local processor ID to the per cpu info struct
  x86/platform/UV: Move scir info to the per cpu info struct
  x86/platform/UV: Create per cpu info structs to replace per hub info structs
  x86/platform/UV: Update MMIOH setup function to work for both UV3 and UV4
  x86/platform/UV: Clean up redunduncies after merge of UV4 MMR definitions
  x86/platform/UV: Add UV4 Specific MMR definitions
  x86/platform/UV: Prep for UV4 MMR updates
  x86/platform/UV: Add UV MMR Illegal Access Function
  x86/platform/UV: Add UV4 Specific Defines
  x86/platform/UV: Add UV Architecture Defines
  x86/platform/UV: Add Initial UV4 definitions
  ...

Pull x86 debug cleanup from Ingo Molnar:
 "A printk() output simplification"

* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/dumpstack: Combine some printk()s

Pull x86 cleanup from Ingo Molnar:
 "Inline optimizations"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Fix non-static inlines

Pull x86-64 defconfig update from Ingo Molnar:
 "Small defconfig addition"

[ I'm not actually convinced our defconfig is sensible, but whatever ]

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build/defconfig/64: Enable CONFIG_E1000E=y

Pull x86 boot updates from Ingo Molnar:
 "The biggest changes in this cycle were:

   - prepare for more KASLR related changes, by restructuring, cleaning
     up and fixing the existing boot code.  (Kees Cook, Baoquan He,
     Yinghai Lu)

   - simplifly/concentrate subarch handling code, eliminate
     paravirt_enabled() usage.  (Luis R Rodriguez)"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
  x86/KASLR: Clarify purpose of each get_random_long()
  x86/KASLR: Add virtual address choosing function
  x86/KASLR: Return earliest overlap when avoiding regions
  x86/KASLR: Add 'struct slot_area' to manage random_addr slots
  x86/boot: Add missing file header comments
  x86/KASLR: Initialize mapping_info every time
  x86/boot: Comment what finalize_identity_maps() does
  x86/KASLR: Build identity mappings on demand
  x86/boot: Split out kernel_ident_mapping_init()
  x86/boot: Clean up indenting for asm/boot.h
  x86/KASLR: Improve comments around the mem_avoid[] logic
  x86/boot: Simplify pointer casting in choose_random_location()
  x86/KASLR: Consolidate mem_avoid[] entries
  x86/boot: Clean up pointer casting
  x86/boot: Warn on future overlapping memcpy() use
  x86/boot: Extract error reporting functions
  x86/boot: Correctly bounds-check relocations
  x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size'
  x86/boot: Fix "run_size" calculation
  x86/boot: Calculate decompression size during boot not build
  ...

Pull x86 asm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - MSR access API fixes and enhancements (Andy Lutomirski)

   - early exception handling improvements (Andy Lutomirski)

   - user-space FS/GS prctl usage fixes and improvements (Andy
     Lutomirski)

   - Remove the cpu_has_*() APIs and replace them with equivalents
     (Borislav Petkov)

   - task switch micro-optimization (Brian Gerst)

   - 32-bit entry code simplification (Denys Vlasenko)

   - enhance PAT handling in enumated CPUs (Toshi Kani)

  ... and lots of other cleanups/fixlets"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  x86/arch_prctl/64: Restore accidentally removed put_cpu() in ARCH_SET_GS
  x86/entry/32: Remove asmlinkage_protect()
  x86/entry/32: Remove GET_THREAD_INFO() from entry code
  x86/entry, sched/x86: Don't save/restore EFLAGS on task switch
  x86/asm/entry/32: Simplify pushes of zeroed pt_regs->REGs
  selftests/x86/ldt_gdt: Test set_thread_area() deletion of an active segment
  x86/tls: Synchronize segment registers in set_thread_area()
  x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbase
  x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G optimization
  x86/segments/64: When load_gs_index fails, clear the base
  x86/segments/64: When loadsegment(fs, ...) fails, clear the base
  x86/asm: Make asm/alternative.h safe from assembly
  x86/asm: Stop depending on ptrace.h in alternative.h
  x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall()
  x86/asm: Make sure verify_cpu() has a good stack
  x86/extable: Add a comment about early exception handlers
  x86/msr: Set the return value to zero when native_rdmsr_safe() fails
  x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y
  x86/paravirt: Add paravirt_{read,write}_msr()
  x86/msr: Carry on after a non-"safe" MSR access fails
  ...

Pull scheduler updates from Ingo Molnar:

 - massive CPU hotplug rework (Thomas Gleixner)

 - improve migration fairness (Peter Zijlstra)

 - CPU load calculation updates/cleanups (Yuyang Du)

 - cpufreq updates (Steve Muckle)

 - nohz optimizations (Frederic Weisbecker)

 - switch_mm() micro-optimization on x86 (Andy Lutomirski)

 - ... lots of other enhancements, fixes and cleanups.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
  ARM: Hide finish_arch_post_lock_switch() from modules
  sched/core: Provide a tsk_nr_cpus_allowed() helper
  sched/core: Use tsk_cpus_allowed() instead of accessing ->cpus_allowed
  sched/loadavg: Fix loadavg artifacts on fully idle and on fully loaded systems
  sched/fair: Correct unit of load_above_capacity
  sched/fair: Clean up scale confusion
  sched/nohz: Fix affine unpinned timers mess
  sched/fair: Fix fairness issue on migration
  sched/core: Kill sched_class::task_waking to clean up the migration logic
  sched/fair: Prepare to fix fairness problems on migration
  sched/fair: Move record_wakee()
  sched/core: Fix comment typo in wake_q_add()
  sched/core: Remove unused variable
  sched: Make hrtick_notifier an explicit call
  sched/fair: Make ilb_notifier an explicit call
  sched/hotplug: Make activate() the last hotplug step
  sched/hotplug: Move migration CPU_DYING to sched_cpu_dying()
  sched/migration: Move CPU_ONLINE into scheduler state
  sched/migration: Move calc_load_migrate() into CPU_DYING
  sched/migration: Move prepare transition to SCHED_STARTING state
  ...

Pull RAS updates from Ingo Molnar:
 "Main changes in this cycle were:

   - AMD MCE/RAS handling updates (Yazen Ghannam, Aravind
     Gopalakrishnan)

   - Cleanups (Borislav Petkov)

   - logging fix (Tony Luck)"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/RAS: Add SMCA support to AMD Error Injector
  EDAC, mce_amd: Detect SMCA using X86_FEATURE_SMCA
  x86/mce: Update AMD mcheck init to use cpu_has() facilities
  x86/cpu: Add detection of AMD RAS Capabilities
  x86/mce/AMD: Save an indentation level in prepare_threshold_block()
  x86/mce/AMD: Disable LogDeferredInMcaStat for SMCA systems
  x86/mce/AMD: Log Deferred Errors using SMCA MCA_DE{STAT,ADDR} registers
  x86/mce: Detect local MCEs properly
  x86/mce: Look in genpool instead of mcelog for pending error records
  x86/mce: Detect and use SMCA-specific msr_ops
  x86/mce: Define vendor-specific MSR accessors
  x86/mce: Carve out writes to MCx_STATUS and MCx_CTL
  x86/mce: Grade uncorrected errors for SMCA-enabled systems
  x86/mce: Log MCEs after a warm rest on AMD, Fam17h and later
  x86/mce: Remove explicit smp_rmb() when starting CPUs sync
  x86/RAS: Rename AMD MCE injector config item

Pull perf updates from Ingo Molnar:
 "Bigger kernel side changes:

   - Add backwards writing capability to the perf ring-buffer code,
     which is preparation for future advanced features like robust
     'overwrite support' and snapshot mode.  (Wang Nan)

   - Add pause and resume ioctls for the perf ringbuffer (Wang Nan)

   - x86 Intel cstate code cleanups and reorgnization (Thomas Gleixner)

   - x86 Intel uncore and CPU PMU driver updates (Kan Liang, Peter
     Zijlstra)

   - x86 AUX (Intel PT) related enhancements and updates (Alexander
     Shishkin)

   - x86 MSR PMU driver enhancements and updates (Huang Rui)

   - ... and lots of other changes spread out over 40+ commits.

  Biggest tooling side changes:

   - 'perf trace' features and enhancements.  (Arnaldo Carvalho de Melo)

   - BPF tooling updates (Wang Nan)

   - 'perf sched' updates (Jiri Olsa)

   - 'perf probe' updates (Masami Hiramatsu)

   - ... plus 200+ other enhancements, fixes and cleanups to tools/

  The merge commits, the shortlog and the changelogs contain a lot more
  details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (249 commits)
  perf/core: Disable the event on a truncated AUX record
  perf/x86/intel/pt: Generate PMI in the STOP region as well
  perf buildid-cache: Use lsdir() for looking up buildid caches
  perf symbols: Use lsdir() for the search in kcore cache directory
  perf tools: Use SBUILD_ID_SIZE where applicable
  perf tools: Fix lsdir to set errno correctly
  perf trace: Move seccomp args beautifiers to tools/perf/trace/beauty/
  perf trace: Move flock op beautifier to tools/perf/trace/beauty/
  perf build: Add build-test for debug-frame on arm/arm64
  perf build: Add build-test for libunwind cross-platforms support
  perf script: Fix export of callchains with recursion in db-export
  perf script: Fix callchain addresses in db-export
  perf script: Fix symbol insertion behavior in db-export
  perf symbols: Add dso__insert_symbol function
  perf scripting python: Use Py_FatalError instead of die()
  perf tools: Remove xrealloc and ALLOC_GROW
  perf help: Do not use ALLOC_GROW in add_cmd_list
  perf pmu: Make pmu_formats_string to check return value of strbuf
  perf header: Make topology checkers to check return value of strbuf
  perf tools: Make alias handler to check return value of strbuf
  ...

Pull support for killable rwsems from Ingo Molnar:
 "This, by Michal Hocko, implements down_write_killable().

  The main usecase will be to update mm_sem usage sites to use this new
  API, to allow the mm-reaper introduced in commit aac45363 ("mm,
  oom: introduce oom reaper") to tear down oom victim address spaces
  asynchronously with minimum latencies and without deadlock worries"

[ The vfs will want it too as the inode lock is changed from a mutex to
  a rwsem due to the parallel lookup and readdir updates ]

* 'locking-rwsem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Fix comment on register clobbering
  locking/rwsem: Fix down_write_killable()
  locking/rwsem, x86: Add frame annotation for call_rwsem_down_write_failed_killable()
  locking/rwsem: Provide down_write_killable()
  locking/rwsem, x86: Provide __down_write_killable()
  locking/rwsem, s390: Provide __down_write_killable()
  locking/rwsem, ia64: Provide __down_write_killable()
  locking/rwsem, alpha: Provide __down_write_killable()
  locking/rwsem: Introduce basis for down_write_killable()
  locking/rwsem, sparc: Drop superfluous arch specific implementation
  locking/rwsem, sh: Drop superfluous arch specific implementation
  locking/rwsem, xtensa: Drop superfluous arch specific implementation
  locking/rwsem: Drop explicit memory barriers
  locking/rwsem: Get rid of __down_write_nested()

Pull locking changes from Ingo Molnar:
 "The main changes in this cycle were:

   - pvqspinlock statistics fixes (Davidlohr Bueso)

   - flip atomic_fetch_or() arguments (Peter Zijlstra)

   - locktorture simplification (Paul E.  McKenney)

   - documentation updates (SeongJae Park, David Howells, Davidlohr
     Bueso, Paul E McKenney, Peter Zijlstra, Will Deacon)

   - various fixes"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/atomics: Flip atomic_fetch_or() arguments
  locking/pvqspinlock: Robustify init_qspinlock_stat()
  locking/pvqspinlock: Avoid double resetting of stats
  lcoking/locktorture: Simplify the torture_runnable computation
  locking/Documentation: Clarify that ACQUIRE applies to loads, RELEASE applies to stores
  locking/Documentation: State purpose of memory-barriers.txt
  locking/Documentation: Add disclaimer
  locking/Documentation/lockdep: Fix spelling mistakes
  locking/lockdep: Deinline register_lock_class(), save 2328 bytes
  locking/locktorture: Fix NULL pointer dereference for cleanup paths
  locking/locktorture: Fix deboosting NULL pointer dereference
  locking/Documentation: Mention smp_cond_acquire()
  locking/Documentation: Insert white spaces consistently
  locking/Documentation: Fix formatting inconsistencies
  locking/Documentation: Add missed subsection in TOC
  locking/Documentation: Fix missed s/lock/acquire renames
  locking/Documentation: Clarify relationship of barrier() to control dependencies

Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Drop the unused EFI_SYSTEM_TABLES efi.flags bit and ensure the
     ARM/arm64 EFI System Table mapping is read-only (Ard Biesheuvel)

   - Add a comment to explain that one of the code paths in the x86/pat
     code is only executed for EFI boot (Matt Fleming)

   - Improve Secure Boot status checks on arm64 and handle unexpected
     errors (Linn Crosetto)

   - Remove the global EFI memory map variable 'memmap' as the same
     information is already available in efi::memmap (Matt Fleming)

   - Add EFI Memory Attribute table support for ARM/arm64 (Ard
     Biesheuvel)

   - Add EFI GOP framebuffer support for ARM/arm64 (Ard Biesheuvel)

   - Add EFI Bootloader Control driver for storing reboot(2) data in EFI
     variables for consumption by bootloaders (Jeremy Compostella)

   - Add Core EFI capsule support (Matt Fleming)

   - Add EFI capsule char driver (Kweh, Hock Leong)

   - Unify EFI memory map code for ARM and arm64 (Ard Biesheuvel)

   - Add generic EFI support for detecting when firmware corrupts CPU
     status register bits (like IRQ flags) when performing EFI runtime
     service calls (Mark Rutland)

  ... and other misc cleanups"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  efivarfs: Make efivarfs_file_ioctl() static
  efi: Merge boolean flag arguments
  efi/capsule: Move 'capsule' to the stack in efi_capsule_supported()
  efibc: Fix excessive stack footprint warning
  efi/capsule: Make efi_capsule_pending() lockless
  efi: Remove unnecessary (and buggy) .memmap initialization from the Xen EFI driver
  efi/runtime-wrappers: Remove ARCH_EFI_IRQ_FLAGS_MASK #ifdef
  x86/efi: Enable runtime call flag checking
  arm/efi: Enable runtime call flag checking
  arm64/efi: Enable runtime call flag checking
  efi/runtime-wrappers: Detect firmware IRQ flag corruption
  efi/runtime-wrappers: Remove redundant #ifdefs
  x86/efi: Move to generic {__,}efi_call_virt()
  arm/efi: Move to generic {__,}efi_call_virt()
  arm64/efi: Move to generic {__,}efi_call_virt()
  efi/runtime-wrappers: Add {__,}efi_call_virt() templates
  efi/arm-init: Reserve rather than unmap the memory map for ARM as well
  efi: Add misc char driver interface to update EFI firmware
  x86/efi: Force EFI reboot to process pending capsules
  efi: Add 'capsule' update support
  ...

Pull core signal updates from Ingo Molnar:
 "These updates from Stas Sergeev and Andy Lutomirski, improve the
  sigaltstack interface by extending its ABI with the SS_AUTODISARM
  feature, which makes it possible to use swapcontext() in a sighandler
  that works on sigaltstack.  Without this flag, the subsequent signal
  will corrupt the state of the switched-away sighandler.

  The inspiration is more robust dosemu signal handling"

* 'core-signals-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  signals/sigaltstack: Change SS_AUTODISARM to (1U << 31)
  signals/sigaltstack: Report current flag bits in sigaltstack()
  selftests/sigaltstack: Fix the sigaltstack test on old kernels
  signals/sigaltstack: If SS_AUTODISARM, bypass on_sig_stack()
  selftests/sigaltstack: Add new testcase for sigaltstack(SS_ONSTACK|SS_AUTODISARM)
  signals/sigaltstack: Implement SS_AUTODISARM flag
  signals/sigaltstack: Prepare to add new SS_xxx flags
  signals/sigaltstack, x86/signals: Unify the x86 sigaltstack check with other architectures

Pull RCU updates from Ingo Molnar:
 "The main changes are:

   - Documentation updates, including fixes to the design-level
     requirements documentation and a fixed version of the design-level
     data-structure documentation.  These fixes include removing
     cartoons and getting rid of the html/htmlx duplication.

   - Further improvements to the new-age expedited grace periods.

   - Miscellaneous fixes.

   - Torture-test changes, including a new rcuperf module for measuring
     RCU grace-period performance and scalability, which is useful for
     the expedited-grace-period changes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  rcutorture: Add boot-time adjustment of leaf fanout
  rcutorture: Add irqs-disabled test for call_rcu()
  rcutorture: Dump trace buffer upon shutdown
  rcutorture: Don't rebuild identical kernel
  rcutorture: Add OS-jitter capability
  documentation: Add documentation for RCU's major data structures
  rcutorture: Convert test duration to seconds early
  torture: Kill qemu, not parent process
  torture: Clarify refusal to run more than one torture test
  rcutorture: Consider FROZEN hotplug notifier transitions
  rcutorture: Remove redundant initialization to zero
  rcuperf: Do not wake up shutdown wait queue if "shutdown" is false.
  rcutorture: Add largish-system rcuperf scenario
  rcutorture: Avoid RCU CPU stall warning and RT throttling
  rcutorture: Add rcuperf holdoff boot parameter to reduce interference
  rcutorture: Make scripts analyze rcuperf trace data, if present
  rcutorture: Make rcuperf collect expedited event-trace data
  rcutorture: Print measure of batching efficiency
  rcutorture: Set rcuperf writer kthreads to real-time priority
  rcutorture: Bind rcuperf reader/writer kthreads to CPUs
  ...

Pull core/lib update from Ingo Molnar:
 "This contains a single commit that removes an unused facility that the
  scheduler used to make use of"

* 'core-lib-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lib/proportions: Remove unused code

The hash mixing between adding the next 64 bits of name
was just a bit weak.

Replaced with a still very fast but slightly more effective
mixing function.
Signed-off-by: George Spelvin <linux@horizon.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Document explicitly that %edx can get clobbered on the slow path, on
32-bit kernels. Something I learned the hard way. :-\
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-next@vger.kernel.org
Link: http://lkml.kernel.org/r/20160516093428.GA26108@pd.tnicSigned-off-by: Ingo Molnar <mingo@kernel.org>

The new signal_pending exit path in __rwsem_down_write_failed_common()
was fingered as breaking his kernel by Tetsuo Handa.

Upon inspection it was found that there are two things wrong with it;

 - it forgets to remove WAITING_BIAS if it leaves the list empty, or
 - it forgets to wake further waiters that were blocked on the now
   removed waiter.

Especially the first issue causes new lock attempts to block and stall
indefinitely, as the code assumes that pending waiters mean there is
an owner that will wake when it releases the lock.
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Waiman Long <Waiman.Long@hpe.com>
Link: http://lkml.kernel.org/r/20160512115745.GP3192@twins.programming.kicks-ass.netSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull x86 fix from Thomas Gleixner:
 "Just the missing compat entry for the new pread/writev2"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Use compat version for preadv2 and pwritev2

Pull networking fixes from David Miller:

 1) Fix mvneta/bm dependencies, from Arnd Bergmann.

 2) RX completion hw bug workaround in bnxt_en, from Michael Chan.

 3) Kernel pointer leak in nf_conntrack, from Linus.

 4) Hoplimit route attribute limits not enforced properly, from Paolo
    Abeni.

 5) qlcnic driver NULL deref fix from Dan Carpenter.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  arm64: bpf: jit JMP_JSET_{X,K}
  net/route: enforce hoplimit max value
  nf_conntrack: avoid kernel pointer value leak in slab name
  drivers: net: xgene: fix register offset
  drivers: net: xgene: fix statistics counters race condition
  drivers: net: xgene: fix ununiform latency across queues
  drivers: net: xgene: fix sharing of irqs
  drivers: net: xgene: fix IPv4 forward crash
  xen-netback: fix extra_info handling in xenvif_tx_err()
  net: mvneta: bm: fix dependencies again
  bnxt_en: Add workaround to detect bad opaque in rx completion (part 2)
  bnxt_en: Add workaround to detect bad opaque in rx completion (part 1)
  qlcnic: potential NULL dereference in qlcnic_83xx_get_minidump_template()

Original implementation commit e54bcde3 ("arm64: eBPF JIT compiler")
had the relevant code paths, but due to an oversight always fail jiting.

As a result, we had been falling back to BPF interpreter whenever a BPF
program has JMP_JSET_{X,K} instructions.

With this fix, we confirm that the corresponding tests in lib/test_bpf
continue to pass, and also jited.

...
[    2.784553] test_bpf: #30 JSET jited:1 188 192 197 PASS
[    2.791373] test_bpf: #31 tcpdump port 22 jited:1 325 677 625 PASS
[    2.808800] test_bpf: #32 tcpdump complex jited:1 323 731 991 PASS
...
[    3.190759] test_bpf: #237 JMP_JSET_K: if (0x3 & 0x2) return 1 jited:1 110 PASS
[    3.192524] test_bpf: #238 JMP_JSET_K: if (0x3 & 0xffffffff) return 1 jited:1 98 PASS
[    3.211014] test_bpf: #249 JMP_JSET_X: if (0x3 & 0x2) return 1 jited:1 120 PASS
[    3.212973] test_bpf: #250 JMP_JSET_X: if (0x3 & 0xffffffff) return 1 jited:1 89 PASS
...

Fixes: e54bcde3 ("arm64: eBPF JIT compiler")
Signed-off-by: Zi Shen Lim <zlim.lnx@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, when creating or updating a route, no check is performed
in both ipv4 and ipv6 code to the hoplimit value.

The caller can i.e. set hoplimit to 256, and when such route will
 be used, packets will be sent with hoplimit/ttl equal to 0.

This commit adds checks for the RTAX_HOPLIMIT value, in both ipv4
ipv6 route code, substituting any value greater than 255 with 255.

This is consistent with what is currently done for ADVMSS and MTU
in the ipv4 code.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The slab name ends up being visible in the directory structure under
/sys, and even if you don't have access rights to the file you can see
the filenames.

Just use a 64-bit counter instead of the pointer to the 'net' structure
to generate a unique name.

This code will go away in 4.7 when the conntrack code moves to a single
kmemcache, but this is the backportable simple solution to avoiding
leaking kernel pointers to user space.

Fixes: 5b3501fa ("netfilter: nf_conntrack: per netns nf_conntrack_cachep")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull vfs fixes from Al Viro:
 "Overlayfs fixes from Miklos, assorted fixes from me.

  Stable fodder of varying severity, all sat in -next for a while"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ovl: ignore permissions on underlying lookup
  vfs: add lookup_hash() helper
  vfs: rename: check backing inode being equal
  vfs: add vfs_select_inode() helper
  get_rock_ridge_filename(): handle malformed NM entries
  ecryptfs: fix handling of directory opening
  atomic_open(): fix the handling of create_error
  fix the copy vs. map logics in blk_rq_map_user_iov()
  do_splice_to(): cap the size before passing to ->splice_read()

Iyappan Subramanian says:

====================
drivers: net: xgene: Bug fixes

This patch set addresses the following bug fixes that were found during testing.

  1. IPv4 forward test crash
    - drivers: net: xgene: fix IPv4 forward crash

  2. Sharing of irqs
    - drivers: net: xgene: fix sharing of irqs

  3. Ununiform latency across queues
    - drivers: net: xgene: fix ununiform latency across queues

  4. Fix statistics counters race condition
    - drivers: net: xgene: fix statistics counters race condition

  5. Correcting register offset and field lengths
    - drivers: net: xgene: fix register offset

v2: Address review comments from v1
- Defer TSO fix, and reposting all other patches from v1

v1:
- Initial version
====================
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes SG_RX_DV_GATE_REG_0_ADDR register offset
and ring state field lengths.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes the race condition on updating the statistics
counters by moving the counters to the ring structure.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch addresses ununiform latency across queues by adding
more queues to match with, upto number of CPU cores.

Also, number of interrupts are increased and the channel numbers
are reordered.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since hardware doesn't allow sharing of interrupts,
this patch fixes the same by removing IRQF_SHARED flag.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes the crash observed during IPv4 forward test by
setting the drop field in the dbptr.
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Toan Le <toanle@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull cgroup fixes from Tejun Heo:
 "During v4.6-rc1 cgroup namespace support was merged.  There is an
  issue where it's impossible to tell whether a given cgroup mount point
  is bind mounted or namespaced.  Serge has been working on the issue
  but it took longer than expected to resolve, so the late pull request.

  Given that it's a completely new feature and the patches don't touch
  anything else, the risk seems acceptable.  However, if this is too
  late, an alternative is plugging new cgroup ns creation for v4.6 and
  retrying for v4.7"

* 'for-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix compile warning
  kernfs: kernfs_sop_show_path: don't return 0 after seq_dentry call
  cgroup, kernfs: make mountinfo show properly scoped path for cgroup namespaces
  kernfs_path_from_node_locked: don't overwrite nlen

Pull workqueue fix from Tejun Heo:
 "CPU hotplug callbacks can invoke DOWN_FAILED w/o preceding
  DOWN_PREPARE which can trigger a WARN_ON() in workqueue.

  The bug has been there for a very long time.  It only triggers if CPU
  down fails at a specific point and I don't think it has adverse
  effects other than the warning messages.  The fix is very low impact"

* 'for-4.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix rebind bound workers warning

Pull scheduler fix from Ingo Molnar:
 "This is a revert to fix an interactivity problem.

  The proper fixes for the problems that the reverted commit exposed are
  now in sched/core (consisting of 3 patches), but were too risky for
  v4.6 and will arrive in the v4.7 merge window"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "sched/fair: Fix fairness issue on migration"

Pull perf fixes from Ingo Molnar:
 "An uncharacteristically large number of bugs popped up in the last
  week:

   - various tooling fixes, two crashes and build problems
   - two Intel PT fixes
   - an KNL uncore driver fix
   - an Intel PMU driver fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf stat: Fallback to user only counters when perf_event_paranoid > 1
  perf evsel: Handle EACCESS + perf_event_paranoid=2 in fallback()
  perf evsel: Improve EPERM error handling in open_strerror()
  tools lib traceevent: Do not reassign parg after collapse_tree()
  perf probe: Check if dwarf_getlocations() is available
  perf dwarf: Guard !x86_64 definitions under #ifdef else clause
  perf tools: Use readdir() instead of deprecated readdir_r()
  perf thread_map: Use readdir() instead of deprecated readdir_r()
  perf script: Use readdir() instead of deprecated readdir_r()
  perf tools: Use readdir() instead of deprecated readdir_r()
  perf/core: Disable the event on a truncated AUX record
  perf/x86/intel/pt: Generate PMI in the STOP region as well
  perf/x86: Fix undefined shift on 32-bit kernels
  perf/x86/msr: Fix SMI overflow
  perf/x86/intel/uncore: Fix CHA registers configuration procedure for Knights Landing platform
  perf diff: Fix duplicated output column

Pull ARM SoC fixes from Arnd Bergmann:
 "Three more bug fixes for ARM SoCs this week:

   - The Atmel sama5d2 was registering the wrong NFC device type

   - On Atmel sam9x5, the power management controller had an incorrect
     register area size

   - On ARM64 Allwinner machine was not secting the generic irqchip
     code, causing build errors in some configurations"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: dts: at91: sam9x5: Fix the memory range assigned to the PMC
  arm64/sunxi: 4.6-rc1: Add dependency on generic irq chip
  ARM: dts: at91: sama5d2: use "atmel,sama5d3-nfc" compatible for nfc

Merge tag 'regulator-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fixes from Mark Brown:
 "A small collection of driver specific fixes for the regulator
  subsysetem:

   - Fix handling of probe deferral for GPIO regulators

   - Fix a typo in the module alias for DA9053

   - Fix the definition of BUCK9 in the S2MPS11 driver.  This change
     looks larger than it is because an irregularity in the hardware
     means that the macro used to define bucks 6-10 needs duplicating
     and tweaking to have a separate macro for 9

   - Fix a series of errors in the definitions of the LDOs the AXP20x
     regulators, some of which had always been present and some of which
     were introduced in the merge window"

* tag 'regulator-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: da9063: Correct module alias prefix to fix module autoloading
  regulator: axp20x: Fix axp22x ldo_io registration error on cold boot
  regulator: axp20x: Fix axp22x ldo_io voltage ranges
  regulator: axp20x: Fix LDO4 linear voltage range
  regulator: s2mps11: Fix invalid selector mask and voltages for buck9
  regulator: gpio: check return value of of_get_named_gpio

Pull regmap fixes from Mark Brown:
 "This is rather too late so it'd be completely understandable if you
  don't want to pull it at this point, I had thought I'd sent this
  earlier but it seems I didn't.  Everything has been in -next for some
  time now.

  The main set of fixes here are mopping up some more issues with MMIO,
  fixing handling of endianness configuration in DT (which just wasn't
  working at all) and cases where the register and value endianness are
  different.

  There is also a fix for bulk register reads on SPMI"

* tag 'regmap-fix-v4.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: spmi: Fix regmap_spmi_ext_read in multi-byte case
  regmap: mmio: Explicitly say little endian is the defualt in the bus config
  regmap: mmio: Parse endianness definitions from DT
  regmap: Fix implicit inclusion of device.h
  regmap: mmio: Fix value endianness selection
  regmap: fix documentation to match code