This one sneaked in through vfs tree with commit 2b777c9d
("ceph_sync_read: stop poking into iov_iter guts").
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

Pull scsi target fixes from Nicholas Bellinger:
 "Apologies for the late pull request.

  Here are the outstanding target-pending fixes for v4.1 code.

  The series contains three patches from Sagi + Co that address a few
  iser-target issues that have been uncovered during recent testing at
  Mellanox.

  Patch #1 has a v3.16+ stable tag, and #2-3 have v3.10+ stable tags"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  iser-target: Fix possible use-after-free
  iser-target: release stale iser connections
  iser-target: Fix variable-length response error completion

Pull drm fixes from Dave Airlie:
 "A smattering of fixes,

  mgag200:
      don't accept modes that aren't aligned properly as hw can't do it

  i915:
      two regression fixes

  radeon:
      one query to allow userspace fixes
      one oops fixer for older hw with new options enabled"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: don't probe MST on hw we don't support it on
  drm/radeon: Add RADEON_INFO_VA_UNMAP_WORKING query
  drm/mgag200: Reject non-character-cell-aligned mode widths
  Revert "drm/i915: Don't skip request retirement if the active list is empty"
  drm/i915: Always reset vma->ggtt_view.pages cache on unbinding

Pull clk fixes from Michael Turquette:
 "Very late clk regression fixes for the ARM-based AT91 platform.

  These went unnoticed by me until recently, hence the late pull
  request"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: at91: fix h32mx prototype inclusion in pmc header
  clk: at91: trivial: typo in peripheral clock description
  clk: at91: fix PERIPHERAL_MAX_SHIFT definition
  clk: at91: pll: fix input range validity check

Pull sound fixes from Takashi Iwai:
 "Nothing looks scary, just a few usual HD-audio regression fixes and
  fixup, in addition to a minor Kconfig dependency fix for the old MIPS
  drivers"

* tag 'sound-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Fix unused label skip_i915
  ALSA: hda - Fix noisy outputs on Dell XPS13 (2015 model)
  ALSA: mips: let SND_SGI_O2 select SND_PCM
  ALSA: hda - Fix audio crackles on Dell Latitude E7x40
  ALSA: hda - adding a DAC/pin preference map for a HP Envy TS machine

Trivial fix that prevents to compile this pmc clock driver if h32mx clock is
present but smd clock isn't.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Fixes: bcc5fd49 ("clk: at91: add a driver for the h32mx clock")
Cc: <stable@vger.kernel.org> # 3.18+

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Fix the PERIPHERAL_MAX_SHIFT definition (3 instead of 4) and adapt the
round_rate and set_rate logic accordingly.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: "Wu, Songjun" <Songjun.Wu@atmel.com>

The PLL impose a certain input range to work correctly, but it appears that
this input range does not apply on the input clock (or parent clock) but
on the input clock after it has passed the PLL divisor.
Fix the implementation accordingly.

Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Jonas Andersson <jonas@microbit.se>

Pull i2c documentation fix from Wolfram Sang:
 "Here is a small documentation fix for I2C.

  We already had a user who unsuccessfully tried to get the new slave
  framework running with the currently broken example.  So, before this
  happens again, I'd like to have this how-to-use section fixed for 4.1
  already.  So that no more hacking time is wasted"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: slave: fix the example how to instantiate from userspace

Revert commit 534b483a ("cpumask: don't perform while loop in
cpumask_next_and()").

This was a minor optimization, but it puts a `struct cpumask' on the
stack, which consumes too much stack space.

Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Amir Vadai <amirv@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

one fix, one revert
* tag 'drm-intel-fixes-2015-06-18' of git://anongit.freedesktop.org/drm-intel:
  Revert "drm/i915: Don't skip request retirement if the active list is empty"
  drm/i915: Always reset vma->ggtt_view.pages cache on unbinding

two radeon fixes
	one MST fix,
	one query addition, destined for stable, and to fix a regression
* 'drm-fixes-4.1' of git://people.freedesktop.org/~deathsimple/linux:
  drm/radeon: don't probe MST on hw we don't support it on
  drm/radeon: Add RADEON_INFO_VA_UNMAP_WORKING query

If you do radeon.mst=1 on a gpu without mst hw, and then
plug some mst hw it will oops instead of falling back.

So check we have DCE5 at least before proceeding.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Christian König <christian.koenig@amd.com>

This tells userspace that it's safe to use the RADEON_VA_UNMAP operation
of the DRM_RADEON_GEM_VA ioctl.

Cc: stable@vger.kernel.org
(NOTE: Backporting this commit requires at least backports of commits
26d4d129,
48afbd70 and
c29c0876 as well, otherwise using
RADEON_VA_UNMAP runs into trouble)
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>

Merge tag 'trace-fix-filter-4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing filter fix from Steven Rostedt:
 "Vince Weaver reported a warning when he added perf event filters into
  his fuzzer tests.  There's a missing check of balanced operations when
  parenthesis are used, and this triggers a WARN_ON() and when reading
  the failure, the filter reports no failure occurred.

  The operands were not being checked if they match, this adds that"

* tag 'trace-fix-filter-4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have filter check for balanced ops

Pull kvm bugfix from Marcelo Tosatti:
 "Rrestore APIC migration functionality"

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: fix lapic.timer_mode on restore

Since when we start discussions about the usage Media Controller for
complex hardware, one thing become clear: the way it is, MC fails to
map anything different than capture/output/m2m video-only streaming.

The point is that MC has entities named as devnodes, but the only
devnode used (before the DVB patches) is MEDIA_ENT_T_DEVNODE_V4L.
Due to the way MC got implemented, however, this entity actually
doesn't represent the devnode, but the hardware I/O engine that
receives data via DMA.

By coincidence, such DMA is associated with the V4L device node
on webcam hardware, but this is not true even for other V4L2
devices. For example, on USB hardware, the DMA is done via the
USB controller. The data passes though a in-kernel filter that
strips off the URB headers. Other V4L2 devices like radio may not
even have DMA. When it have, the DMA is done via ALSA, and not
via the V4L devnode.

In other words, MC is broken as a whole, but tagging it as BROKEN
right now would do more harm than good.

So, instead, let's mark, for now, the DVB part as broken and
block all new changes to MC while we fix this mess, whith
we hopefully will do for the next Kernel version.
Requested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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

   - Crash in caam hash due to uninitialised buffer lengths.

   - Alignment issue in caam RNG that may lead to non-random output"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: caam - fix RNG buffer cache alignment
  crypto: caam - improve initalization for context state saves

It appears that, at some point last year, XFS made directory handling
changes which bring it into lockdep conflict with shmem_zero_setup():
it is surprising that mmap() can clone an inode while holding mmap_sem,
but that has been so for many years.

Since those few lockdep traces that I've seen all implicated selinux,
I'm hoping that we can use the __shmem_file_setup(,,,S_PRIVATE) which
v3.13's commit c7277090 ("security: shmem: implement kernel private
shmem inodes") introduced to avoid LSM checks on kernel-internal inodes:
the mmap("/dev/zero") cloned inode is indeed a kernel-internal detail.

This also covers the !CONFIG_SHMEM use of ramfs to support /dev/zero
(and MAP_SHARED|MAP_ANONYMOUS).  I thought there were also drivers
which cloned inode in mmap(), but if so, I cannot locate them now.
Reported-and-tested-by: Prarit Bhargava <prarit@redhat.com>
Reported-and-tested-by: Daniel Wagner <wagi@monom.org>
Reported-and-tested-by: Morten Stevens <mstevens@fedoraproject.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

I copied the wrong shell code into the documentation. Sorry to all who
tried to get sense out of this current example :/ Slight rewording while
we are here.
Reported-by: Tim Bakker <bakkert@mymail.vcu.edu>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

When the following filter is used it causes a warning to trigger:

 # cd /sys/kernel/debug/tracing
 # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter
-bash: echo: write error: Invalid argument
 # cat events/ext4/ext4_truncate_exit/filter
((dev==1)blocks==2)
^
parse_error: No error

 ------------[ cut here ]------------
 WARNING: CPU: 2 PID: 1223 at kernel/trace/trace_events_filter.c:1640 replace_preds+0x3c5/0x990()
 Modules linked in: bnep lockd grace bluetooth  ...
 CPU: 3 PID: 1223 Comm: bash Tainted: G        W       4.1.0-rc3-test+ #450
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012
  0000000000000668 ffff8800c106bc98 ffffffff816ed4f9 ffff88011ead0cf0
  0000000000000000 ffff8800c106bcd8 ffffffff8107fb07 ffffffff8136b46c
  ffff8800c7d81d48 ffff8800d4c2bc00 ffff8800d4d4f920 00000000ffffffea
 Call Trace:
  [<ffffffff816ed4f9>] dump_stack+0x4c/0x6e
  [<ffffffff8107fb07>] warn_slowpath_common+0x97/0xe0
  [<ffffffff8136b46c>] ? _kstrtoull+0x2c/0x80
  [<ffffffff8107fb6a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff81159065>] replace_preds+0x3c5/0x990
  [<ffffffff811596b2>] create_filter+0x82/0xb0
  [<ffffffff81159944>] apply_event_filter+0xd4/0x180
  [<ffffffff81152bbf>] event_filter_write+0x8f/0x120
  [<ffffffff811db2a8>] __vfs_write+0x28/0xe0
  [<ffffffff811dda43>] ? __sb_start_write+0x53/0xf0
  [<ffffffff812e51e0>] ? security_file_permission+0x30/0xc0
  [<ffffffff811dc408>] vfs_write+0xb8/0x1b0
  [<ffffffff811dc72f>] SyS_write+0x4f/0xb0
  [<ffffffff816f5217>] system_call_fastpath+0x12/0x6a
 ---[ end trace e11028bd95818dcd ]---

Worse yet, reading the error message (the filter again) it says that
there was no error, when there clearly was. The issue is that the
code that checks the input does not check for balanced ops. That is,
having an op between a closed parenthesis and the next token.

This would only cause a warning, and fail out before doing any real
harm, but it should still not caues a warning, and the error reported
should work:

 # cd /sys/kernel/debug/tracing
 # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter
-bash: echo: write error: Invalid argument
 # cat events/ext4/ext4_truncate_exit/filter
((dev==1)blocks==2)
^
parse_error: Meaningless filter expression

And give no kernel warning.

Link: http://lkml.kernel.org/r/20150615175025.7e809215@gandalf.local.home

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: stable@vger.kernel.org # 2.6.31+
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

When CONFIG_SND_HDA_I915=n, we get a compile warning:
  sound/pci/hda/hda_intel.c: In function ‘azx_probe_continue’:
  sound/pci/hda/hda_intel.c:1882:2: warning: label ‘skip_i915’ defined but not used [-Wunused-label]

Fix it by putting again ifdef to it.  Sigh.

Fixes: bf06848b ('ALSA: hda - Continue probing even if i915 binding fails')
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

The hwrng output buffers (2) are cast inside of a a struct (caam_rng_ctx)
allocated in one DMA-tagged region. While the kernel's heap allocator
should place the overall struct on a cacheline aligned boundary, the 2
buffers contained within may not necessarily align. Consenquently, the ends
of unaligned buffers may not fully flush, and if so, stale data will be left
behind, resulting in small repeating patterns.

This fix aligns the buffers inside the struct.

Note that not all of the data inside caam_rng_ctx necessarily needs to be
DMA-tagged, only the buffers themselves require this. However, a fix would
incur the expense of error-handling bloat in the case of allocation failure.

Cc: stable@vger.kernel.org
Signed-off-by: Steve Cornelius <steve.cornelius@freescale.com>
Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Multiple function in asynchronous hashing use a saved-state block,
a.k.a. struct caam_hash_state, which holds a stash of information
between requests (init/update/final). Certain values in this state
block are loaded for processing using an inline-if, and when this
is done, the potential for uninitialized data can pose conflicts.
Therefore, this patch improves initialization of state data to
prevent false assignments using uninitialized data in the state block.

This patch addresses the following traceback, originating in
ahash_final_ctx(), although a problem like this could certainly
exhibit other symptoms:

kernel BUG at arch/arm/mm/dma-mapping.c:465!
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = 80004000
[00000000] *pgd=00000000
Internal error: Oops: 805 [#1] PREEMPT SMP
Modules linked in:
CPU: 0    Not tainted  (3.0.15-01752-gdd441b9-dirty #40)
PC is at __bug+0x1c/0x28
LR is at __bug+0x18/0x28
pc : [<80043240>]    lr : [<8004323c>]    psr: 60000013
sp : e423fd98  ip : 60000013  fp : 0000001c
r10: e4191b84  r9 : 00000020  r8 : 00000009
r7 : 88005038  r6 : 00000001  r5 : 2d676572  r4 : e4191a60
r3 : 00000000  r2 : 00000001  r1 : 60000093  r0 : 00000033
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 1000404a  DAC: 00000015
Process cryptomgr_test (pid: 1306, stack limit = 0xe423e2f0)
Stack: (0xe423fd98 to 0xe4240000)
fd80:                                                       11807fd1 80048544
fda0: 88005000 e4191a00 e5178040 8039dda0 00000000 00000014 2d676572 e4191008
fdc0: 88005018 e4191a60 00100100 e4191a00 00000000 8039ce0c e423fea8 00000007
fde0: e4191a00 e4227000 e5178000 8039ce18 e419183c 80203808 80a94a44 00000006
fe00: 00000000 80207180 00000000 00000006 e423ff08 00000000 00000007 e5178000
fe20: e41918a4 80a949b4 8c4844e2 00000000 00000049 74227000 8c4844e2 00000e90
fe40: 0000000e 74227e90 ffff8c58 80ac29e0 e423fed4 8006a350 8c81625c e423ff5c
fe60: 00008576 e4002500 00000003 00030010 e4002500 00000003 e5180000 e4002500
fe80: e5178000 800e6d24 007fffff 00000000 00000010 e4001280 e4002500 60000013
fea0: 000000d0 804df078 00000000 00000000 00000000 00000000 00000000 00000000
fec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
fee0: 00000000 00000000 e4227000 e4226000 e4753000 e4752000 e40a5000 e40a4000
ff00: e41e7000 e41e6000 00000000 00000000 00000000 e423ff14 e423ff14 00000000
ff20: 00000400 804f9080 e5178000 e4db0b40 00000000 e4db0b80 0000047c 00000400
ff40: 00000000 8020758c 00000400 ffffffff 0000008a 00000000 e4db0b40 80206e00
ff60: e4049dbc 00000000 00000000 00000003 e423ffa4 80062978 e41a8bfc 00000000
ff80: 00000000 e4049db4 00000013 e4049db0 00000013 00000000 00000000 00000000
ffa0: e4db0b40 e4db0b40 80204cbc 00000013 00000000 00000000 00000000 80204cfc
ffc0: e4049da0 80089544 80040a40 00000000 e4db0b40 00000000 00000000 00000000
ffe0: e423ffe0 e423ffe0 e4049da0 800894c4 80040a40 80040a40 00000000 00000000
[<80043240>] (__bug+0x1c/0x28) from [<80048544>] (___dma_single_dev_to_cpu+0x84)
[<80048544>] (___dma_single_dev_to_cpu+0x84/0x94) from [<8039dda0>] (ahash_fina)
[<8039dda0>] (ahash_final_ctx+0x180/0x428) from [<8039ce18>] (ahash_final+0xc/0)
[<8039ce18>] (ahash_final+0xc/0x10) from [<80203808>] (crypto_ahash_op+0x28/0xc)
[<80203808>] (crypto_ahash_op+0x28/0xc0) from [<80207180>] (test_hash+0x214/0x5)
[<80207180>] (test_hash+0x214/0x5b8) from [<8020758c>] (alg_test_hash+0x68/0x8c)
[<8020758c>] (alg_test_hash+0x68/0x8c) from [<80206e00>] (alg_test+0x7c/0x1b8)
[<80206e00>] (alg_test+0x7c/0x1b8) from [<80204cfc>] (cryptomgr_test+0x40/0x48)
[<80204cfc>] (cryptomgr_test+0x40/0x48) from [<80089544>] (kthread+0x80/0x88)
[<80089544>] (kthread+0x80/0x88) from [<80040a40>] (kernel_thread_exit+0x0/0x8)
Code: e59f0010 e1a01003 eb126a8d e3a03000 (e5833000)
---[ end trace d52a403a1d1eaa86 ]---

Cc: stable@vger.kernel.org
Signed-off-by: Steve Cornelius <steve.cornelius@freescale.com>
Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

lapic.timer_mode was not properly initialized after migration, which
broke few useful things, like login, by making every sleep eternal.

Fix this by calling apic_update_lvtt in kvm_apic_post_state_restore.

There are other slowpaths that update lvtt, so this patch makes sure
something similar doesn't happen again by calling apic_update_lvtt
after every modification.

Cc: stable@vger.kernel.org
Fixes: f30ebc31 ("KVM: x86: optimize some accesses to LVTT and SPIV")
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Turns out 1366x768 does not in fact work on this hardware.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

The new Dell XPS13 also requires the similar quirk for fixing the
noisy outputs.  (But, as the codec was changed, now the fixup for
Latitude is used instead.)

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=99851Signed-off-by: Takashi Iwai <tiwai@suse.de>

This reverts commit 0aedb162.

I messed things up while applying [1] to drm-intel-fixes. Rectify.

[1] http://mid.gmane.org/1432827156-9605-1-git-send-email-ville.syrjala@linux.intel.com

Fixes: 0aedb162 ("drm/i915: Don't skip request retirement if the active list is empty")
Cc: stable@vger.kernel.org
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Fix the missing dependency on PCM stuff.

[Add the same fix for HAL2, too -- tiwai]
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

We still got a report that the audio crackles and noises occur with
the recent 4.1 kernels on Dell machines.  These machines seem to need
similar workarounds that have been applied to the recent Dell XPS 13
models.  Since the codec of these machines (Dell Latitute E7240 and
E7440) is different from XPS 13's one, we need a new fixup entry.

Also, it was confirmed that the previous workaround to disable the
widget power-save (commit [219f47e4: ALSA: hda - Disable widget
power-saving for ALC292 & co]) is no longer needed after this fix.
So, this patch includes the partial revert of the commit, too.
Reported-and-tested-by: Mihai Donțu <mihai.dontu@gmail.com>
Tested-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

On a HP Envy TouchSmart laptop, there are 2 speakers (main speaker
and subwoofer speaker), 1 headphone and 2 DACs, without this fixup,
the headphone will be assigned to a DAC and the 2 speakers will be
assigned to another DAC, this assignment makes the surround-2.1
channels invalid.

To fix it, here using a DAC/pin preference map to bind the main
speaker to 1 DAC and the subwoofer speaker will be assigned to another
DAC.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

With the introduction of multiple views of an obj in the same vm, each
vma was taught to cache its copy of the pages (so that different views
could have different page arrangements). However, this missed decoupling
those vma->ggtt_view.pages when the vma released its reference on the
obj->pages. As we don't always free the vma, this leads to a possible
scenario (e.g. execbuffer interrupted by the shrinker) where the vma
points to a stale obj->pages, and explodes.

Fixes regression from commit fe14d5f4
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Wed Dec 10 17:27:58 2014 +0000

    drm/i915: Infrastructure for supporting different GGTT views per object

Tvrtko says, if someone else will be confused how this can happen, key
is the reservation execbuffer path. That puts the VMA on the exec_list
which prevents i915_vma_unbind and i915_gem_vma_destroy from fully
destroying the VMA. So the VMA is left existing as an empty object in
the list - unbound and disassociated with the backing store. Kind of a
cached memory object. And then re-using it needs to clear the cached
pages pointer which is fixed above.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1227892Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
[Jani: Added Tvrtko's explanation to commit message.]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Pull dmaengine fixes from Vinod Koul:
 "Here are hopefully last set of fixes for 4.1. This time we have:

   - fixing pause capability reporting on both dmaengine pause & resume
     support by Krzysztof

   - locking fix fir at_xdmac by Ludovic

   - slave configuration fix for at_xdmac by Ludovic"

* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: Fix choppy sound because of unimplemented resume
  dmaengine: at_xdmac: rework slave configuration part
  dmaengine: at_xdmac: lock fixes