Pull thermal fixes from Eduardo Valentin:
 "Last minute fixes on the thermal-soc tree.  There is a fix of a long
  lasting bug in cpu cooling device, thanks for RMK for being pushing
  this"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal/cpu_cooling: update policy limits if clipped_freq < policy->max
  thermal/cpu_cooling: rename max_freq as clipped_freq in notifier
  thermal/cpu_cooling: rename cpufreq_val as clipped_freq
  thermal/cpu_cooling: convert 'switch' block to 'if' block in notifier
  thermal/cpu_cooling: quit early after updating policy
  thermal/cpu_cooling: No need to initialize max_freq to 0
  thermal: cpu_cooling: fix lockdep problems in cpu_cooling
  thermal: power_allocator: do not use devm* interfaces

Pull dmaengine fix from Vinod Koul:
 "We recently found issue with dma_request_slave_channel() API causing
  privatecnt value to go bad.  This is fixed by balancing the privatecnt"

* tag 'dmaengine-fix-4.2-rc8' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: fix balance of privatecnt inc/dec operations

Pull drm fixes from Dave Airlie:
 "These came in late last week, I wanted to look over the mst one before
  forwarding, but it seems good.

  Just three i915 and one MST fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Commit planes on each crtc separately.
  drm/i915: calculate primary visibility changes instead of calling from set_config
  drm/i915: Only dither on 6bpc panels
  drm/dp/mst: Remove port after removing connector.

Pull rdma bugfix from Doug Ledford:
 "Bugfix in iw_cxgb4"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
  iw_cxgb4: gracefully handle unknown CQE status errors

Pull libata fixes from Tejun Heo:
 "Three minor device-specific fixes and revert of NCQ autosense added
  during this -rc1.

  It turned out that NCQ autosense as currently implemented interferes
  with the usual error handling behavior.  It will be revisited in the
  near future"

* 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ata: ahci_brcmstb: Fix misuse of IS_ENABLED
  sata_sx4: Check return code from pdc20621_i2c_read()
  Revert "libata: Implement NCQ autosense"
  Revert "libata: Implement support for sense data reporting"
  Revert "libata-eh: Set 'information' field for autosense"
  ata: ahci_brcmstb: Fix warnings with CONFIG_PM_SLEEP=n

Pull cgroup fix from Tejun Heo:
 "A fix for a subtle bug introduced back during 3.17 cycle which
  interferes with setting configurations under specific conditions"

* 'for-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: use trialcs->mems_allowed as a temp variable

This patch increments privatecnt value and set DMA_PRIVATE in device
caps in dma_request_slave_channel() function. This is needed to keep
privatecnt increment/decrement balance.

As function dma_release_channel() decrements privatecnt counter, we need
to increment it when channel is requested. Otherwise privatecnt drops
into negatives after few dma_release_channel() calls.
Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - a regression caused by the conversion of IPsec ESP to the new AEAD
     interface: ESN with authencesn no longer works because it relied on
     the AD input SG list having a specific layout which is no longer
     the case.  In linux-next authencesn is fixed properly and no longer
     assumes anything about the SG list format.  While for this release
     a minimal fix is applied to authencesn so that it works with the
     new linear layout.

   - fix memory corruption caused by bogus index in the caam hash code.

   - fix powerpc nx SHA hashing which could cause module load failures
     if module signature verification is enabled"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: caam - fix memory corruption in ahash_final_ctx
  crypto: nx - respect sg limit bounds when building sg lists for SHA
  crypto: authencesn - Fix breakage with new ESP code

Pull ARM SoC fixes from Olof Johansson:
 "A smallish batch of fixes, a little more than expected this late, but
  all fixes are contained to their platforms and seem reasonably low
  risk:

   - a somewhat large SMP fix for ux500 that still seemed warranted to
     include here
   - OMAP DT fixes for pbias regulator specification that broke due to
     some DT reshuffling
   - PCIe IRQ routing bugfix for i.MX
   - networking fixes for keystone
   - runtime PM for OMAP GPMC
   - a couple of error path bug fixes for exynos"

* tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file
  ARM: dts: keystone: fix the clock node for mdio
  memory: omap-gpmc: Don't try to save uninitialized GPMC context
  ARM: imx6: correct i.MX6 PCIe interrupt routing
  ARM: ux500: add an SMP enablement type and move cpu nodes
  ARM: dts: dra7: Fix broken pbias device creation
  ARM: dts: OMAP5: Fix broken pbias device creation
  ARM: dts: OMAP4: Fix broken pbias device creation
  ARM: dts: omap243x: Fix broken pbias device creation
  ARM: EXYNOS: fix double of_node_put() on error path
  ARM: EXYNOS: Fix potentian kfree() of ro memory

Pull MIPS bugfix from Ralf Baechle:
 "Only a single MIPS fix - the math when invoking syscall_trace_enter
  was wrong"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Fix seccomp syscall argument for MIPS64

Merge x86 fixes from Ingo Molnar:
 "Two followup fixes related to the previous LDT fix"

Also applied a further FPU emulation fix from Andy Lutomirski to the
branch before actually merging it.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
  x86/ldt: Further fix FPU emulation
  x86/ldt: Correct FPU emulation access to LDT
  x86/ldt: Correct LDT access in single stepping logic

The previous fix confused a selector with a segment prefix.  Fix it.

Compile-tested only.

Cc: stable@vger.kernel.org
Cc: Juergen Gross <jgross@suse.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: 4809146b ("x86/ldt: Correct FPU emulation access to LDT")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fuse_dev_ioctl() performed fuse_get_dev() on a user-supplied fd,
leading to a type confusion issue. Fix it by checking file->f_op.
Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'keystone-dts-late-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into fixes

ARM: Couple of Keysyone MDIO DTS fixes for 4.2-rc6+

These are necessary to get the NIC card working on all Keystone
EVMs. Couple of boards are broken without these two fixes.

* tag 'keystone-dts-late-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone:
  ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file
  ARM: dts: keystone: fix the clock node for mdio
Signed-off-by: Olof Johansson <olof@lixom.net>

Commit 4c21b8fd ("MIPS: seccomp: Handle indirect system calls (o32)")
fixed indirect system calls on O32 but it also introduced a bug for MIPS64
where it erroneously modified the v0 (syscall) register with the assumption
that the sycall offset hasn't been taken into consideration. This breaks
seccomp on MIPS64 n64 and n32 ABIs. We fix this by replacing the addition
with a move instruction.

Fixes: 4c21b8fd ("MIPS: seccomp: Handle indirect system calls (o32)")
Cc: <stable@vger.kernel.org> # 3.15+
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10951/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Pull SCSI fixes from James Bottomley:
 "This has two libfc fixes for bugs causing rare crashes, one iscsi fix
  for a potential hang on shutdown, and a fix for an I/O blocksize issue
  which caused a regression"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  sd: Fix maximum I/O size for BLOCK_PC requests
  libfc: Fix fc_fcp_cleanup_each_cmd()
  libfc: Fix fc_exch_recv_req() error path
  libiscsi: Fix host busy blocking during connection teardown

single MST fixes from Maarten.

* tag 'topic/drm-fixes-2015-08-14' of git://anongit.freedesktop.org/drm-intel:
  drm/dp/mst: Remove port after removing connector.

three display fixes for Intel.

* tag 'drm-intel-fixes-2015-08-14' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Commit planes on each crtc separately.
  drm/i915: calculate primary visibility changes instead of calling from set_config
  drm/i915: Only dither on 6bpc panels

policy->max is the maximum allowed frequency defined by user and
clipped_freq is the maximum that thermal constraints allow.

If clipped_freq is lower than policy->max, then we need to readjust
policy->max.

But, if clipped_freq is greater than policy->max, we don't need to do
anything. We used to call cpufreq_verify_within_limits() in this case,
but it doesn't change anything in this case.

Lets skip this unnecessary call and write a comment that explains this.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

That's what it is for, lets name it properly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

That's what it is for, lets name it properly.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

We just need to take care of single event here and there is no need to
increase indentation level of most of the code (which causes lines
longer that 80 columns to break).

Kill the switch block.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

If a valid cpufreq_dev is found for policy->cpu, we should update the
policy and quit the for loop. There is no need to keep traversing the
list of cpufreq_dev's.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

Its always set before getting used, don't initialize it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

A recent change to the cpu_cooling code introduced a AB-BA deadlock
scenario between the cpufreq_policy_notifier_list rwsem and the
cooling_cpufreq_lock.  This is caused by cooling_cpufreq_lock being held
before the registration/removal of the notifier block (an operation
which takes the rwsem), and the notifier code itself which takes the
locks in the reverse order:

======================================================
[ INFO: possible circular locking dependency detected ]
3.18.0+ #1453 Not tainted
-------------------------------------------------------
rc.local/770 is trying to acquire lock:
 (cooling_cpufreq_lock){+.+.+.}, at: [<c04abfc4>] cpufreq_thermal_notifier+0x34/0xfc

but task is already holding lock:
 ((cpufreq_policy_notifier_list).rwsem){++++.+}, at: [<c0042f04>]  __blocking_notifier_call_chain+0x34/0x68

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 ((cpufreq_policy_notifier_list).rwsem){++++.+}:
       [<c06bc3b0>] down_write+0x44/0x9c
       [<c0043444>] blocking_notifier_chain_register+0x28/0xd8
       [<c04ad610>] cpufreq_register_notifier+0x68/0x90
       [<c04abe4c>] __cpufreq_cooling_register.part.1+0x120/0x180
       [<c04abf44>] __cpufreq_cooling_register+0x98/0xa4
       [<c04abf8c>] cpufreq_cooling_register+0x18/0x1c
       [<bf0046f8>] imx_thermal_probe+0x1c0/0x470 [imx_thermal]
       [<c037cef8>] platform_drv_probe+0x50/0xac
       [<c037b710>] driver_probe_device+0x114/0x234
       [<c037b8cc>] __driver_attach+0x9c/0xa0
       [<c0379d68>] bus_for_each_dev+0x5c/0x90
       [<c037b204>] driver_attach+0x24/0x28
       [<c037ae7c>] bus_add_driver+0xe0/0x1d8
       [<c037c0cc>] driver_register+0x80/0xfc
       [<c037cd80>] __platform_driver_register+0x50/0x64
       [<bf007018>] 0xbf007018
       [<c0008a5c>] do_one_initcall+0x88/0x1d8
       [<c0095da4>] load_module+0x1768/0x1ef8
       [<c0096614>] SyS_init_module+0xe0/0xf4
       [<c000ec00>] ret_fast_syscall+0x0/0x48

-> #0 (cooling_cpufreq_lock){+.+.+.}:
       [<c00619f8>] lock_acquire+0xb0/0x124
       [<c06ba3b4>] mutex_lock_nested+0x5c/0x3d8
       [<c04abfc4>] cpufreq_thermal_notifier+0x34/0xfc
       [<c0042bf4>] notifier_call_chain+0x4c/0x8c
       [<c0042f20>] __blocking_notifier_call_chain+0x50/0x68
       [<c0042f58>] blocking_notifier_call_chain+0x20/0x28
       [<c04ae62c>] cpufreq_set_policy+0x7c/0x1d0
       [<c04af3cc>] store_scaling_governor+0x74/0x9c
       [<c04ad418>] store+0x90/0xc0
       [<c0175384>] sysfs_kf_write+0x54/0x58
       [<c01746b4>] kernfs_fop_write+0xdc/0x190
       [<c010dcc0>] vfs_write+0xac/0x1b4
       [<c010dfec>] SyS_write+0x44/0x90
       [<c000ec00>] ret_fast_syscall+0x0/0x48

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((cpufreq_policy_notifier_list).rwsem);
                               lock(cooling_cpufreq_lock);
                               lock((cpufreq_policy_notifier_list).rwsem);
  lock(cooling_cpufreq_lock);

 *** DEADLOCK ***

7 locks held by rc.local/770:
 #0:  (sb_writers#6){.+.+.+}, at: [<c010dda0>] vfs_write+0x18c/0x1b4
 #1:  (&of->mutex){+.+.+.}, at: [<c0174678>] kernfs_fop_write+0xa0/0x190
 #2:  (s_active#52){.+.+.+}, at: [<c0174680>] kernfs_fop_write+0xa8/0x190
 #3:  (cpu_hotplug.lock){++++++}, at: [<c0026a60>] get_online_cpus+0x34/0x90
 #4:  (cpufreq_rwsem){.+.+.+}, at: [<c04ad3e0>] store+0x58/0xc0
 #5:  (&policy->rwsem){+.+.+.}, at: [<c04ad3f8>] store+0x70/0xc0
 #6:  ((cpufreq_policy_notifier_list).rwsem){++++.+}, at: [<c0042f04>] __blocking_notifier_call_chain+0x34/0x68

stack backtrace:
CPU: 0 PID: 770 Comm: rc.local Not tainted 3.18.0+ #1453
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Backtrace:
[<c00121c8>] (dump_backtrace) from [<c0012360>] (show_stack+0x18/0x1c)
 r6:c0b85a80 r5:c0b75630 r4:00000000 r3:00000000
[<c0012348>] (show_stack) from [<c06b6c48>] (dump_stack+0x7c/0x98)
[<c06b6bcc>] (dump_stack) from [<c06b42a4>] (print_circular_bug+0x28c/0x2d8)
 r4:c0b85a80 r3:d0071d40
[<c06b4018>] (print_circular_bug) from [<c00613b0>] (__lock_acquire+0x1acc/0x1bb0)
 r10:c0b50660 r8:c09e6d80 r7:d0071d40 r6:c11d0f0c r5:00000007 r4:d0072240
[<c005f8e4>] (__lock_acquire) from [<c00619f8>] (lock_acquire+0xb0/0x124)
 r10:00000000 r9:c04abfc4 r8:00000000 r7:00000000 r6:00000000 r5:c0a06f0c
 r4:00000000
[<c0061948>] (lock_acquire) from [<c06ba3b4>] (mutex_lock_nested+0x5c/0x3d8)
 r10:ec853800 r9:c0a06ed4 r8:d0071d40 r7:c0a06ed4 r6:c11d0f0c r5:00000000
 r4:c04abfc4
[<c06ba358>] (mutex_lock_nested) from [<c04abfc4>] (cpufreq_thermal_notifier+0x34/0xfc)
 r10:ec853800 r9:ec85380c r8:d00d7d3c r7:c0a06ed4 r6:d00d7d3c r5:00000000
 r4:fffffffe
[<c04abf90>] (cpufreq_thermal_notifier) from [<c0042bf4>] (notifier_call_chain+0x4c/0x8c)
 r7:00000000 r6:00000000 r5:00000000 r4:fffffffe
[<c0042ba8>] (notifier_call_chain) from [<c0042f20>] (__blocking_notifier_call_chain+0x50/0x68)
 r8:c0a072a4 r7:00000000 r6:d00d7d3c r5:ffffffff r4:c0a06fc8 r3:ffffffff
[<c0042ed0>] (__blocking_notifier_call_chain) from [<c0042f58>] (blocking_notifier_call_chain+0x20/0x28)
 r7:ec98b540 r6:c13ebc80 r5:ed76e600 r4:d00d7d3c
[<c0042f38>] (blocking_notifier_call_chain) from [<c04ae62c>] (cpufreq_set_policy+0x7c/0x1d0)
[<c04ae5b0>] (cpufreq_set_policy) from [<c04af3cc>] (store_scaling_governor+0x74/0x9c)
 r7:ec98b540 r6:0000000c r5:ec98b540 r4:ed76e600
[<c04af358>] (store_scaling_governor) from [<c04ad418>] (store+0x90/0xc0)
 r6:0000000c r5:ed76e6d4 r4:ed76e600
[<c04ad388>] (store) from [<c0175384>] (sysfs_kf_write+0x54/0x58)
 r8:0000000c r7:d00d7f78 r6:ec98b540 r5:0000000c r4:ec853800 r3:0000000c
[<c0175330>] (sysfs_kf_write) from [<c01746b4>] (kernfs_fop_write+0xdc/0x190)
 r6:ec98b540 r5:00000000 r4:00000000 r3:c0175330
[<c01745d8>] (kernfs_fop_write) from [<c010dcc0>] (vfs_write+0xac/0x1b4)
 r10:0162aa70 r9:d00d6000 r8:0000000c r7:d00d7f78 r6:0162aa70 r5:0000000c
 r4:eccde500
[<c010dc14>] (vfs_write) from [<c010dfec>] (SyS_write+0x44/0x90)
 r10:0162aa70 r8:0000000c r7:eccde500 r6:eccde500 r5:00000000 r4:00000000
[<c010dfa8>] (SyS_write) from [<c000ec00>] (ret_fast_syscall+0x0/0x48)
 r10:00000000 r8:c000edc4 r7:00000004 r6:000216cc r5:0000000c r4:0162aa70

Solve this by moving to finer grained locking - use one mutex to protect
the cpufreq_dev_list as a whole, and a separate lock to ensure correct
ordering of cpufreq notifier registration and removal.

cooling_list_lock is taken within cooling_cpufreq_lock on
(un)registration to preserve the behavior of the code, i.e. to
atomically add/remove to the list and (un)register the notifier.

Fixes: 2dcd851f ("thermal: cpu_cooling: Update always cpufreq policy with
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

Pull KVM fixes from Paolo Bonzini:
 "Just two very small & simple patches"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST
  KVM: x86: zero IDT limit on entry to SMM

Merge fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  Update maintainers for DRM STI driver
  mm: cma: mark cma_bitmap_maxno() inline in header
  zram: fix pool name truncation
  memory-hotplug: fix wrong edge when hot add a new node
  .mailmap: Andrey Ryabinin has moved
  ipc/sem.c: update/correct memory barriers
  mm/hwpoison: fix panic due to split huge zero page
  ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()
  ipc,sem: fix use after free on IPC_RMID after a task using same semaphore set exits
  mm/hwpoison: fix fail isolate hugetlbfs page w/ refcount held
  mm/hwpoison: fix page refcount of unknown non LRU page

Pull clock fix from Stephen Boyd:
 "A one-liner for a regression found in the PXA clock driver"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: pxa: pxa3xx: fix CKEN register access

Add Vincent Abriou and myself as maintainers.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

cma_bitmap_maxno() was marked as static and not static inline, which can
cause warnings about this function not being used if this file is included
in a file that does not call that function, and violates the conventions
used elsewhere.  The two options are to move the function implementation
back to mm/cma.c or make it inline here, and it's simple enough for the
latter to make sense.
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

zram_meta_alloc() constructs a pool name for zs_create_pool() call as

    snprintf(pool_name, sizeof(pool_name), "zram%d", device_id);

However, it defines pool name buffer to be only 8 bytes long (minus
trailing zero), which means that we can have only 1000 pool names: zram0
-- zram999.

With CONFIG_ZSMALLOC_STAT enabled an attempt to create a device zram1000
can fail if device zram100 already exists, because snprintf() will
truncate new pool name to zram100 and pass it debugfs_create_dir(),
causing:

  debugfs dir <zram100> creation failed
  zram: Error creating memory pool

... and so on.

Fix it by passing zram->disk->disk_name to zram_meta_alloc() instead of
divice_id.  We construct zram%d name earlier and keep it as a ->disk_name,
no need to snprintf() it again.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When we add a new node, the edge of memory may be wrong.

e.g. system has 4 nodes, and node3 is movable, node3 mem:[24G-32G],

1. hotremove the node3,
2. then hotadd node3 with a part of memory, mem:[26G-30G],
3. call hotadd_new_pgdat()
        free_area_init_node()
                get_pfn_range_for_nid()
4. it will return wrong start_pfn and end_pfn, because we have not
update the memblock.

This patch also fixes a BUG_ON during hot-addition, please see
http://marc.info/?l=linux-kernel&m=142961156129456&w=2Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update my email address.
Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sem_lock() did not properly pair memory barriers:

!spin_is_locked() and spin_unlock_wait() are both only control barriers.
The code needs an acquire barrier, otherwise the cpu might perform read
operations before the lock test.

As no primitive exists inside <include/spinlock.h> and since it seems
noone wants another primitive, the code creates a local primitive within
ipc/sem.c.

With regards to -stable:

The change of sem_wait_array() is a bugfix, the change to sem_lock() is a
nop (just a preprocessor redefinition to improve the readability).  The
bugfix is necessary for all kernels that use sem_wait_array() (i.e.:
starting from 3.10).
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Kirill Tkhai <ktkhai@parallels.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: <stable@vger.kernel.org>	[3.10+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Bug:

  ------------[ cut here ]------------
  kernel BUG at mm/huge_memory.c:1957!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: snd_hda_codec_hdmi i915 rpcsec_gss_krb5 snd_hda_codec_realtek snd_hda_codec_generic nfsv4 dns_re
  CPU: 2 PID: 2576 Comm: test_huge Not tainted 4.2.0-rc5-mm1+ #27
  Hardware name: Dell Inc. OptiPlex 7020/0F5C5X, BIOS A03 01/08/2015
  task: ffff880204e3d600 ti: ffff8800db16c000 task.ti: ffff8800db16c000
  RIP: split_huge_page_to_list+0xdb/0x120
  Call Trace:
    memory_failure+0x32e/0x7c0
    madvise_hwpoison+0x8b/0x160
    SyS_madvise+0x40/0x240
    ? do_page_fault+0x37/0x90
    entry_SYSCALL_64_fastpath+0x12/0x71
  Code: ff f0 41 ff 4c 24 30 74 0d 31 c0 48 83 c4 08 5b 41 5c 41 5d c9 c3 4c 89 e7 e8 e2 58 fd ff 48 83 c4 08 31 c0
  RIP  split_huge_page_to_list+0xdb/0x120
   RSP <ffff8800db16fde8>
  ---[ end trace aee7ce0df8e44076 ]---

Testcase:

    #define _GNU_SOURCE
    #include <stdlib.h>
    #include <stdio.h>
    #include <sys/mman.h>
    #include <unistd.h>
    #include <fcntl.h>
    #include <sys/types.h>
    #include <errno.h>
    #include <string.h>

    #define MB 1024*1024

    int main(void)
    {
            char *mem;

            posix_memalign((void **)&mem, 2 * MB, 200 * MB);

            madvise(mem, 200 * MB, MADV_HWPOISON);

            free(mem);

            return 0;
    }

Huge zero page is allocated if page fault w/o FAULT_FLAG_WRITE flag.
The get_user_pages_fast() which called in madvise_hwpoison() will get
huge zero page if the page is not allocated before.  Huge zero page is a
tranparent huge page, however, it is not an anonymous page.
memory_failure will split the huge zero page and trigger
BUG_ON(is_huge_zero_page(page));

After commit 98ed2b00 ("mm/memory-failure: give up error handling
for non-tail-refcounted thp"), memory_failure will not catch non anon
thp from madvise_hwpoison path and this bug occur.

Fix it by catching non anon thp in memory_failure in order to not split
huge zero page in madvise_hwpoison path.

After this patch:

  Injecting memory failure for page 0x202800 at 0x7fd8ae800000
  MCE: 0x202800: non anonymous thp
  [...]

[akpm@linux-foundation.org: remove second split, per Wanpeng]
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

After we acquire the sma->sem_perm lock in exit_sem(), we are protected
against a racing IPC_RMID operation.  Also at that point, we are the last
user of sem_undo_list.  Therefore it isn't required that we acquire or use
ulp->lock.
Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Acked-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Rafael Aquini <aquini@redhat.com>
CC: Aristeu Rozanski <aris@redhat.com>
Cc: David Jeffery <djeffery@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The current semaphore code allows a potential use after free: in
exit_sem we may free the task's sem_undo_list while there is still
another task looping through the same semaphore set and cleaning the
sem_undo list at freeary function (the task called IPC_RMID for the same
semaphore set).

For example, with a test program [1] running which keeps forking a lot
of processes (which then do a semop call with SEM_UNDO flag), and with
the parent right after removing the semaphore set with IPC_RMID, and a
kernel built with CONFIG_SLAB, CONFIG_SLAB_DEBUG and
CONFIG_DEBUG_SPINLOCK, you can easily see something like the following
in the kernel log:

   Slab corruption (Not tainted): kmalloc-64 start=ffff88003b45c1c0, len=64
   000: 6b 6b 6b 6b 6b 6b 6b 6b 00 6b 6b 6b 6b 6b 6b 6b  kkkkkkkk.kkkkkkk
   010: ff ff ff ff 6b 6b 6b 6b ff ff ff ff ff ff ff ff  ....kkkk........
   Prev obj: start=ffff88003b45c180, len=64
   000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a  .....N......ZZZZ
   010: ff ff ff ff ff ff ff ff c0 fb 01 37 00 88 ff ff  ...........7....
   Next obj: start=ffff88003b45c200, len=64
   000: 00 00 00 00 ad 4e ad de ff ff ff ff 5a 5a 5a 5a  .....N......ZZZZ
   010: ff ff ff ff ff ff ff ff 68 29 a7 3c 00 88 ff ff  ........h).<....
   BUG: spinlock wrong CPU on CPU#2, test/18028
   general protection fault: 0000 [#1] SMP
   Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib]
   CPU: 2 PID: 18028 Comm: test Not tainted 4.2.0-rc5+ #1
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
   RIP: spin_dump+0x53/0xc0
   Call Trace:
     spin_bug+0x30/0x40
     do_raw_spin_unlock+0x71/0xa0
     _raw_spin_unlock+0xe/0x10
     freeary+0x82/0x2a0
     ? _raw_spin_lock+0xe/0x10
     semctl_down.clone.0+0xce/0x160
     ? __do_page_fault+0x19a/0x430
     ? __audit_syscall_entry+0xa8/0x100
     SyS_semctl+0x236/0x2c0
     ? syscall_trace_leave+0xde/0x130
     entry_SYSCALL_64_fastpath+0x12/0x71
   Code: 8b 80 88 03 00 00 48 8d 88 60 05 00 00 48 c7 c7 a0 2c a4 81 31 c0 65 8b 15 eb 40 f3 7e e8 08 31 68 00 4d 85 e4 44 8b 4b 08 74 5e <45> 8b 84 24 88 03 00 00 49 8d 8c 24 60 05 00 00 8b 53 04 48 89
   RIP  [<ffffffff810d6053>] spin_dump+0x53/0xc0
    RSP <ffff88003750fd68>
   ---[ end trace 783ebb76612867a0 ]---
   NMI watchdog: BUG: soft lockup - CPU#3 stuck for 22s! [test:18053]
   Modules linked in: 8021q mrp garp stp llc nf_conntrack_ipv4 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc ppdev input_leds joydev parport_pc parport floppy serio_raw virtio_balloon virtio_rng virtio_console virtio_net iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr qxl ttm drm_kms_helper drm snd_hda_codec_generic i2c_piix4 snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore crc32c_intel virtio_pci virtio_ring virtio pata_acpi ata_generic [last unloaded: speedstep_lib]
   CPU: 3 PID: 18053 Comm: test Tainted: G      D         4.2.0-rc5+ #1
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
   RIP: native_read_tsc+0x0/0x20
   Call Trace:
     ? delay_tsc+0x40/0x70
     __delay+0xf/0x20
     do_raw_spin_lock+0x96/0x140
     _raw_spin_lock+0xe/0x10
     sem_lock_and_putref+0x11/0x70
     SYSC_semtimedop+0x7bf/0x960
     ? handle_mm_fault+0xbf6/0x1880
     ? dequeue_task_fair+0x79/0x4a0
     ? __do_page_fault+0x19a/0x430
     ? kfree_debugcheck+0x16/0x40
     ? __do_page_fault+0x19a/0x430
     ? __audit_syscall_entry+0xa8/0x100
     ? do_audit_syscall_entry+0x66/0x70
     ? syscall_trace_enter_phase1+0x139/0x160
     SyS_semtimedop+0xe/0x10
     SyS_semop+0x10/0x20
     entry_SYSCALL_64_fastpath+0x12/0x71
   Code: 47 10 83 e8 01 85 c0 89 47 10 75 08 65 48 89 3d 1f 74 ff 7e c9 c3 0f 1f 44 00 00 55 48 89 e5 e8 87 17 04 00 66 90 c9 c3 0f 1f 00 <55> 48 89 e5 0f 31 89 c1 48 89 d0 48 c1 e0 20 89 c9 48 09 c8 c9
   Kernel panic - not syncing: softlockup: hung tasks

I wasn't able to trigger any badness on a recent kernel without the
proper config debugs enabled, however I have softlockup reports on some
kernel versions, in the semaphore code, which are similar as above (the
scenario is seen on some servers running IBM DB2 which uses semaphore
syscalls).

The patch here fixes the race against freeary, by acquiring or waiting
on the sem_undo_list lock as necessary (exit_sem can race with freeary,
while freeary sets un->semid to -1 and removes the same sem_undo from
list_proc or when it removes the last sem_undo).

After the patch I'm unable to reproduce the problem using the test case
[1].

[1] Test case used below:

    #include <stdio.h>
    #include <sys/types.h>
    #include <sys/ipc.h>
    #include <sys/sem.h>
    #include <sys/wait.h>
    #include <stdlib.h>
    #include <time.h>
    #include <unistd.h>
    #include <errno.h>

    #define NSEM 1
    #define NSET 5

    int sid[NSET];

    void thread()
    {
            struct sembuf op;
            int s;
            uid_t pid = getuid();

            s = rand() % NSET;
            op.sem_num = pid % NSEM;
            op.sem_op = 1;
            op.sem_flg = SEM_UNDO;

            semop(sid[s], &op, 1);
            exit(EXIT_SUCCESS);
    }

    void create_set()
    {
            int i, j;
            pid_t p;
            union {
                    int val;
                    struct semid_ds *buf;
                    unsigned short int *array;
                    struct seminfo *__buf;
            } un;

            /* Create and initialize semaphore set */
            for (i = 0; i < NSET; i++) {
                    sid[i] = semget(IPC_PRIVATE , NSEM, 0644 | IPC_CREAT);
                    if (sid[i] < 0) {
                            perror("semget");
                            exit(EXIT_FAILURE);
                    }
            }
            un.val = 0;
            for (i = 0; i < NSET; i++) {
                    for (j = 0; j < NSEM; j++) {
                            if (semctl(sid[i], j, SETVAL, un) < 0)
                                    perror("semctl");
                    }
            }

            /* Launch threads that operate on semaphore set */
            for (i = 0; i < NSEM * NSET * NSET; i++) {
                    p = fork();
                    if (p < 0)
                            perror("fork");
                    if (p == 0)
                            thread();
            }

            /* Free semaphore set */
            for (i = 0; i < NSET; i++) {
                    if (semctl(sid[i], NSEM, IPC_RMID))
                            perror("IPC_RMID");
            }

            /* Wait for forked processes to exit */
            while (wait(NULL)) {
                    if (errno == ECHILD)
                            break;
            };
    }

    int main(int argc, char **argv)
    {
            pid_t p;

            srand(time(NULL));

            while (1) {
                    p = fork();
                    if (p < 0) {
                            perror("fork");
                            exit(EXIT_FAILURE);
                    }
                    if (p == 0) {
                            create_set();
                            goto end;
                    }

                    /* Wait for forked processes to exit */
                    while (wait(NULL)) {
                            if (errno == ECHILD)
                                    break;
                    };
            }
    end:
            return 0;
    }

[akpm@linux-foundation.org: use normal comment layout]
Signed-off-by: Herton R. Krzesinski <herton@redhat.com>
Acked-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Rafael Aquini <aquini@redhat.com>
CC: Aristeu Rozanski <aris@redhat.com>
Cc: David Jeffery <djeffery@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Hugetlbfs pages will get a refcount in get_any_page() or
madvise_hwpoison() if soft offlining through madvise.  The refcount which
is held by the soft offline path should be released if we fail to isolate
hugetlbfs pages.

Fix it by reducing the refcount for both isolation success and failure.
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>	[3.9+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

After trying to drain pages from pagevec/pageset, we try to get reference
count of the page again, however, the reference count of the page is not
reduced if the page is still not on LRU list.

Fix it by adding the put_page() to drop the page reference which is from
__get_any_page().
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>	[3.9+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>