locking/atomic, arch/arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()

Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).

[wildea01: compile fixes for ll/sc]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

locking/atomic, arch/arm: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()

Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Even with spin_unlock_wait() fixed, nf_conntrack_lock{,_all}() is
borken as it misses a bunch of memory barriers to order the whole
global vs local locks scheme.

Even x86 (and other TSO archs) are affected.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[ Updated the comments. ]
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

With the modified semantics of spin_unlock_wait() a number of
explicit barriers can be removed. Also update the comment for the
do_exit() usecase, as that was somewhat stale/obscure.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This patch updates/fixes all spin_unlock_wait() implementations.

The update is in semantics; where it previously was only a control
dependency, we now upgrade to a full load-acquire to match the
store-release from the spin_unlock() we waited on. This ensures that
when spin_unlock_wait() returns, we're guaranteed to observe the full
critical section we waited on.

This fixes a number of spin_unlock_wait() users that (not
unreasonably) rely on this.

I also fixed a number of ticket lock versions to only wait on the
current lock holder, instead of for a full unlock, as this is
sufficient.

Furthermore; again for ticket locks; I added an smp_rmb() in between
the initial ticket load and the spin loop testing the current value
because I could not convince myself the address dependency is
sufficient, esp. if the loads are of different sizes.

I'm more than happy to remove this smp_rmb() again if people are
certain the address dependency does indeed work as expected.

Note: PPC32 will be fixed independently
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: chris@zankel.net
Cc: cmetcalf@mellanox.com
Cc: davem@davemloft.net
Cc: dhowells@redhat.com
Cc: james.hogan@imgtec.com
Cc: jejb@parisc-linux.org
Cc: linux@armlinux.org.uk
Cc: mpe@ellerman.id.au
Cc: ralf@linux-mips.org
Cc: realmz6@gmail.com
Cc: rkuo@codeaurora.org
Cc: rth@twiddle.net
Cc: schwidefsky@de.ibm.com
Cc: tony.luck@intel.com
Cc: vgupta@synopsys.com
Cc: ysato@users.sourceforge.jp
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Since TILE doesn't do read speculation, its control dependencies also
guarantee LOAD->LOAD order and we don't need the additional RMB
otherwise required to provide ACQUIRE semantics.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Since all asm/barrier.h should/must include asm-generic/barrier.h the
latter is a good place for generic infrastructure like this.

This also allows archs to override the new smp_acquire__after_ctrl_dep().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Introduce smp_acquire__after_ctrl_dep(), this construct is not
uncommon, but the lack of this barrier is.

Use it to better express smp_rmb() uses in WRITE_ONCE(), the IPC
semaphore code and the qspinlock code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This new form allows using hardware assisted waiting.

Some hardware (ARM64 and x86) allow monitoring an address for changes,
so by providing a pointer we can use this to replace the cpu_relax()
with hardware optimized methods in the future.
Requested-by: Will Deacon <will.deacon@arm.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull percpu fixes from Tejun Heo:
 "While adding GFP_ATOMIC support to the percpu allocator, the
  synchronization for the fast-path which doesn't require external
  allocations was separated into pcpu_lock.

  Unfortunately, it incorrectly decoupled async paths and percpu
  chunks could get destroyed while still being operated on.  This
  contains two patches to fix the bug"

* 'for-4.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: fix synchronization between synchronous map extension and chunk destruction
  percpu: fix synchronization between chunk->map_extend_work and chunk destruction

Merge tag 'regulator-fix-v4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

Pull regulator fixes from Mark Brown:
 "Some driver specific fixes for the regulator subsystem:

   - Some of the changes to the core that were merged in the last merge
     window exposed the fact that the qcom-smd driver hadn't implemented
     the voltage enumeration interfaces like it should.  Since it's a
     simple driver specific fix to implement them do that.

   - Fix the ramp delay configuration for tps51632"

* tag 'regulator-fix-v4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: qcom_smd: add list_voltage callback
  regulator: qcom_smd: add regulator ops for pm8941 lnldo
  regulator: qcom_smd: add list_voltage callback
  regulator: tps51632: Fix setting ramp delay

Merge remote-tracking branches 'regulator/fix/qcom-smd' and 'regulator/fix/tps51632' into regulator-linus

This patch adds support to list_voltage callback, so that consumers
like mmc core, can get information of supported voltage range.

Without this patch there is no way for mmc core to know this voltage range.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

Pull thermal management fixes from Zhang Rui:

 - fix an ordering issue in cpu cooling that cooling device is
   registered before it's ready (freq_table being populated).
   (Lukasz Luba)

 - fix a missing comment update (Caesar Wang)

* 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  thermal: add the note for set_trip_temp
  thermal: cpu_cooling: fix improper order during initialization

Pull block layer fixes from Jens Axboe:
 "A small collection of fixes for the current series.  This contains:

   - Two fixes for xen-blkfront, from Bob Liu.

   - A bug fix for NVMe, releasing only the specific resources we
     requested.

   - Fix for a debugfs flags entry for nbd, from Josef.

   - Plug fix from Omar, fixing up a case of code being switched between
     two functions.

   - A missing bio_put() for the new discard callers of
     submit_bio_wait(), fixing a regression causing a leak of the bio.
     From Shaun.

   - Improve dirty limit calculation precision in the writeback code,
     fixing a case where setting a limit lower than 1% of memory would
     end up being zero.  From Tejun"

* 'for-linus' of git://git.kernel.dk/linux-block:
  NVMe: Only release requested regions
  xen-blkfront: fix resume issues after a migration
  xen-blkfront: don't call talk_to_blkback when already connected to blkback
  nbd: pass the nbd pointer for flags debugfs
  block: missing bio_put following submit_bio_wait
  blk-mq: really fix plug list flushing for nomerge queues
  writeback: use higher precision calculation in domain_dirty_limits()

Pull GPIO fixes from Linus Walleij:
 "A new bunch of GPIO fixes for v4.7.

  This time I am very grateful that Ricardo Ribalda Delgado went in and
  fixed my stupid refcounting mistakes in the removal path for GPIO
  chips.  I had a feeling something was wrong here and so it was.  It
  exploded on OMAP and it fixes their problem.  Now it should be (more)
  solid.

  The rest i compilation, Kconfig and driver fixes.  Some tagged for
  stable.

  Summary:

   - Fix a NULL pointer dereference when we are searching the GPIO
     device list but one of the devices have been removed (struct
     gpio_chip pointer is NULL).

   - Fix unaligned reference counters: we were ending on +3 after all
     said and done.  It should be 0.  Remove an extraneous get_device(),
     and call cdev_del() followed by device_del() in gpiochip_remove()
     instead and the count goes to zero and calls the release() function
     properly.

   - Fix a compile warning due to a missing #include in the OF/device
     tree portions.

   - Select ANON_INODES for GPIOLIB, we're using that for our character
     device.  Some randconfig tests disclosed the problem.

   - Make sure the Zynq driver clock runs also without CONFIG_PM enabled

   - Fix an off-by-one error in the 104-DIO-48E driver

   - Fix warnings in bcm_kona_gpio_reset()"

* tag 'gpio-v4.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: bcm-kona: fix bcm_kona_gpio_reset() warnings
  gpio: select ANON_INODES
  gpio: include <linux/io-mapping.h> in gpiolib-of
  gpiolib: Fix unaligned used of reference counters
  gpiolib: Fix NULL pointer deference
  gpio: zynq: initialize clock even without CONFIG_PM
  gpio: 104-dio-48e: Fix control port offset computation off-by-one error

Pull SCSI fixes from James Bottomley:
 "Two current fixes:

   - one affects Qemu CD ROM emulation, which stopped working after the
     updates in SCSI to require VPD pages from all conformant devices.

     Fix temporarily by blacklisting Qemu (we can relax later when they
     come into compliance).

   - The other is a fix to the optimal transfer size.  We set up a
     minefield for ourselves by being confused about whether the limits
     are in bytes or sectors (SCSI optimal is in blocks and the queue
     parameter is in bytes).

     This tries to fix the problem (wrong setting for queue limits
     max_sectors) and make the problem more obvious by introducing a
     wrapper function"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  sd: Fix rw_max for devices that report an optimal xfer size
  scsi: Add QEMU CD-ROM to VPD Inquiry Blacklist

Pull i2c fixes from Wolfram Sang:

 - a bigger fix for i801 to finally be able to be loaded on some
   machines again

 - smaller driver fixes

 - documentation update because of a renamed file

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: mux: reg: Provide of_match_table
  i2c: mux: refer to i2c-mux.txt
  i2c: octeon: Avoid printk after too long SMBUS message
  i2c: octeon: Missing AAK flag in case of I2C_M_RECV_LEN
  i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR

Pull DeviceTree fixes from Rob Herring:

 - fix unflatten_dt_nodes when dad parameter is set.

 - add vendor prefixes for TechNexion and UniWest

 - documentation fix for Marvell BT

 - OF IRQ kerneldoc fixes

 - restrict CMA alignment adjustments to non dma-coherent

 - a couple of warning fixes in reserved-memory code

 - DT maintainers updates

* tag 'devicetree-fixes-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  drivers: of: add definition of early_init_dt_alloc_reserved_memory_arch
  drivers/of: Fix depth for sub-tree blob in unflatten_dt_nodes()
  drivers: of: Fix of_pci.h header guard
  dt-bindings: Add vendor prefix for TechNexion
  of: add vendor prefix for UniWest
  dt: bindings: fix documentation for MARVELL's bt-sd8xxx wireless device
  of: add missing const for of_parse_phandle_with_args() in !CONFIG_OF
  of: silence warnings due to max() usage
  drivers: of: of_reserved_mem: fixup the CMA alignment not to affect dma-coherent
  of: irq: fix of_irq_get[_byname]() kernel-doc
  MAINTAINERS: DeviceTree maintainer updates

Merge tag '20160610_uvc_compat_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux

Pull uvc compat XU ioctl fixes from Andy Lutomirski:
 "uvc's compat XU ioctls go through tons of potentially buggy
  indirection.  The first patch removes the indirection.  The second one
  cleans up the code.

  Compile-tested only.  I have the hardware, but I have absolutely no
  idea what XU does, how to use it, what software to recompile as
  32-bit, or what to test in that software"

* tag '20160610_uvc_compat_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/luto/linux:
  uvc_v4l2: Simplify compat ioctl implementation
  uvc: Forward compat ioctls to their handlers directly

The uvc compat ioctl implementation seems to have copied user data
for no good reason.  Remove a bunch of copies.
Signed-off-by: Andy Lutomirski <luto@kernel.org>

The current code goes through a lot of indirection just to call a
known handler.  Simplify it: just call the handlers directly.

Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>

Pull btrfs fixes from Chris Mason:
 "Has some fixes and some new self tests for btrfs.  The self tests are
  usually disabled in the .config file (unless you're doing btrfs dev
  work), and this bunch is meant to find problems with the 64K page size
  patches.

  Jeff has a patch to help people see if they are using the hardware
  assist crc32c module, which really helps us nail down problems when
  people ask why crcs are using so much CPU.

  Otherwise, it's small fixes"

* 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: self-tests: Fix extent buffer bitmap test fail on BE system
  Btrfs: self-tests: Fix test_bitmaps fail on 64k sectorsize
  Btrfs: self-tests: Use macros instead of constants and add missing newline
  Btrfs: self-tests: Support testing all possible sectorsizes and nodesizes
  Btrfs: self-tests: Execute page straddling test only when nodesize < PAGE_SIZE
  btrfs: advertise which crc32c implementation is being used at module load
  Btrfs: add validadtion checks for chunk loading
  Btrfs: add more validation checks for superblock
  Btrfs: clear uptodate flags of pages in sys_array eb
  Btrfs: self-tests: Support non-4k page size
  Btrfs: Fix integer overflow when calculating bytes_per_bitmap
  Btrfs: test_check_exists: Fix infinite loop when searching for free space entries
  Btrfs: end transaction if we abort when creating uuid root
  btrfs: Use __u64 in exported linux/btrfs.h.

Merge tag 'powerpc-4.7-3Michael Ellerman:' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from
 - ptrace: Fix out of bounds array access warning from Khem Raj
 - pseries: Fix PCI config address for DDW from Gavin Shan
 - pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added
   from Michael Ellerman
 - of: fix autoloading due to broken modalias with no 'compatible' from
   Wolfram Sang
 - radix: Fix always false comparison against MMU_NO_CONTEXT from Aneesh
   Kumar K.V
 - hash: Compute the segment size correctly for ISA 3.0 from Aneesh
   Kumar K.V
 - nohash: Fix build break with 64K pages from Michael Ellerman

* tag 'powerpc-4.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/nohash: Fix build break with 64K pages
  powerpc/mm/hash: Compute the segment size correctly for ISA 3.0
  powerpc/mm/radix: Fix always false comparison against MMU_NO_CONTEXT
  of: fix autoloading due to broken modalias with no 'compatible'
  powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added
  powerpc/pseries: Fix PCI config address for DDW
  powerpc/ptrace: Fix out of bounds array access warning

Merge tag 'hwmon-for-linus-v4.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - fix regression in fam15h_power driver

 - minor variable type fix in lm90 driver

 - document compatible statement for ina2xx driver

* tag 'hwmon-for-linus-v4.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (lm90) use proper type for update_interval
  hwmon: (ina2xx) Document compatible for INA231
  hwmon: (fam15h_power) Disable preemption when reading registers

Merge filesystem stacking fixes from Jann Horn.

* emailed patches from Jann Horn <jannh@google.com>:
  sched: panic on corrupted stack end
  ecryptfs: forbid opening files without mmap handler
  proc: prevent stacking filesystems on top

Until now, hitting this BUG_ON caused a recursive oops (because oops
handling involves do_exit(), which calls into the scheduler, which in
turn raises an oops), which caused stuff below the stack to be
overwritten until a panic happened (e.g.  via an oops in interrupt
context, caused by the overwritten CPU index in the thread_info).

Just panic directly.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This prevents users from triggering a stack overflow through a recursive
invocation of pagefault handling that involves mapping procfs files into
virtual memory.
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This prevents stacking filesystems (ecryptfs and overlayfs) from using
procfs as lower filesystem.  There is too much magic going on inside
procfs, and there is no good reason to stack stuff on top of procfs.

(For example, procfs does access checks in VFS open handlers, and
ecryptfs by design calls open handlers from a kernel thread that doesn't
drop privileges or so.)
Signed-off-by: Jann Horn <jannh@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull arm64 fix from Will Deacon:
 "A fix for an issue that Alex saw whilst swapping with hardware
  access/dirty bit support enabled in the kernel: Fix a failure to fault
  in old pages on a write when CONFIG_ARM64_HW_AFDBM is enabled"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: mm: always take dirty state from new pte in ptep_set_access_flags

Pull x86 fixes from Ingo Molnar:
 "Misc fixes from all around the map, plus a commit that introduces a
  new header of Intel model name symbols (unused) that will make the
  next merge window easier"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ioapic: Fix incorrect pointers in ioapic_setup_resources()
  x86/entry/traps: Don't force in_interrupt() to return true in IST handlers
  x86/cpu/AMD: Extend X86_FEATURE_TOPOEXT workaround to newer models
  x86/cpu/intel: Introduce macros for Intel family numbers
  x86, build: copy ldlinux.c32 to image.iso
  x86/msr: Use the proper trace point conditional for writes

Pull scheduler fixes from Ingo Molnar:
 "Two scheduler debugging fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Fix 'schedstats=enable' cmdline option
  sched/debug: Fix /proc/sched_debug regression

Pull perf fixes from Ingo Molnar:
 "A handful of tooling fixes, two PMU driver fixes and a cleanup of
  redundant code that addresses a security analyzer false positive"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Remove a redundant check
  perf/x86/intel/uncore: Remove SBOX support for Broadwell server
  perf ctf: Convert invalid chars in a string before set value
  perf record: Fix crash when kptr is restricted
  perf symbols: Check kptr_restrict for root
  perf/x86/intel/rapl: Fix pmus free during cleanup

Pull locking fixes from Ingo Molnar:
 "Misc fixes:

   - a file-based futex fix
   - one more spin_unlock_wait() fix
   - a ww-mutex deadlock detection improvement/fix
   - and a raw_read_seqcount_latch() barrier fix"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Calculate the futex key based on a tail page for file-based futexes
  locking/qspinlock: Fix spin_unlock_wait() some more
  locking/ww_mutex: Report recursive ww_mutex locking early
  locking/seqcount: Re-fix raw_read_seqcount_latch()

Pull EFI fixes from Ingo Molnar:
 "Two fixes: a regression/crash fix, and a message output fix"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/arm: Fix the format of EFI debug messages
  efi: Fix for_each_efi_memory_desc_in_map() for empty memmaps

Pull objtool fix from Ingo Molnar:
 "Addresses a false positive warning in the GPU/DRM code"

[ Technically it's not a "false positive", but it's the virtual GPU
  interface that needs the frame pointer for its own internal purposes ]

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool, drm/vmwgfx: Fix "duplicate frame pointer save" warning