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I've seen this trigger twice now, where the i915_gem_object_to_ggtt()
call in intel_unpin_fb_obj() returns NULL, resulting in an oops
immediately afterwards as the (inlined) call to i915_vma_unpin_fence()
tries to dereference it.
It seems to be some race condition where the object is going away at
shutdown time, since both times happened when shutting down the X
server. The call chains were different:
- VT ioctl(KDSETMODE, KD_TEXT):
intel_cleanup_plane_fb+0x5b/0xa0 [i915]
drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
intel_atomic_commit_tail+0x749/0xfe0 [i915]
intel_atomic_commit+0x3cb/0x4f0 [i915]
drm_atomic_commit+0x4b/0x50 [drm]
restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
intel_fbdev_set_par+0x18/0x70 [i915]
fb_set_var+0x236/0x460
fbcon_blank+0x30f/0x350
do_unblank_screen+0xd2/0x1a0
vt_ioctl+0x507/0x12a0
tty_ioctl+0x355/0xc30
do_vfs_ioctl+0xa3/0x5e0
SyS_ioctl+0x79/0x90
entry_SYSCALL_64_fastpath+0x13/0x94
- i915 unpin_work workqueue:
intel_unpin_work_fn+0x58/0x140 [i915]
process_one_work+0x1f1/0x480
worker_thread+0x48/0x4d0
kthread+0x101/0x140
and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.
Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.
[ Reported it originally to the i915 developers on Jan 8, applying the
ugly workaround on my own now after triggering the problem for the
second time with no feedback.
This is likely to be the same bug reported as
https://bugs.freedesktop.org/show_bug.cgi?id=98829
https://bugs.freedesktop.org/show_bug.cgi?id=99134
which has a patch for the underlying problem, but it hasn't gotten to
me, so I'm applying the workaround. ]
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull two parisc fixes from Helge Deller:
"One fix to avoid usage of BITS_PER_LONG in user-space exported swab.h
header which breaks compiling qemu, and one trivial fix for printk
continuation in the parisc parport driver"
* 'parisc-4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Don't use BITS_PER_LONG in userspace-exported swab.h header
parisc, parport_gsc: Fixes for printk continuation lines
Pull i2c fixes from Wolfram Sang:
"Two I2C driver bugfixes.
The 'VLLS mode support' patch should have been entitled 'reconfigure
pinctrl after suspend' to make the bugfix more clear. Sorry, I missed
that, yet didn't want to rebase"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: imx-lpi2c: add VLLS mode support
i2c: i2c-cadence: Initialize configuration before probing devices
In swab.h the "#if BITS_PER_LONG > 32" breaks compiling userspace programs if
BITS_PER_LONG is #defined by userspace with the sizeof() compiler builtin.
Solve this problem by using __BITS_PER_LONG instead. Since we now
#include asm/bitsperlong.h avoid further potential userspace pollution
by moving the #define of SHIFT_PER_LONG to bitops.h which is not
exported to userspace.
This patch unbreaks compiling qemu on hppa/parisc.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Pull NFS client bugfixes from Trond Myklebust:
"Stable patches:
- NFSv4.1: Fix a deadlock in layoutget
- NFSv4 must not bump sequence ids on NFS4ERR_MOVED errors
- NFSv4 Fix a regression with OPEN EXCLUSIVE4 mode
- Fix a memory leak when removing the SUNRPC module
Bugfixes:
- Fix a reference leak in _pnfs_return_layout"
* tag 'nfs-for-4.10-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
pNFS: Fix a reference leak in _pnfs_return_layout
nfs: Fix "Don't increment lock sequence ID after NFS4ERR_MOVED"
SUNRPC: cleanup ida information when removing sunrpc module
NFSv4.0: always send mode in SETATTR after EXCLUSIVE4
nfs: Don't increment lock sequence ID after NFS4ERR_MOVED
NFSv4.1: Fix a deadlock in layoutget
When system enters VLLS mode, module power is turned off. As a result,
all registers are reset to HW default value. After exiting VLLS mode,
registers are still in default mode. As a result, the pinctrl settings
are incorrect, which will affect the module function.
The patch recovers the pinctrl setting when exit VLLS mode.
Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
[wsa: added missing include]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Pull MD fixes from Shaohua Li:
"This fixes several corner cases for raid5 cache, which is merged into
this cycle"
* tag 'md/4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md/r5cache: disable write back for degraded array
md/r5cache: shift complex rmw from read path to write path
md/r5cache: flush data only stripes in r5l_recovery_log()
md/raid5: move comment of fetch_block to right location
md/r5cache: read data into orig_page for prexor of cached data
md/raid5-cache: delete meaningless code
IF NFS_LAYOUT_RETURN_REQUESTED is not set, then we currently exit
without freeing the list of invalidated layout segments, leading
to a reference leak.
Reported-by: Olga Kornievskaia <aglo@umich.edu>
Fixes: 24408f5282 ("pNFS: Fix bugs in _pnfs_return_layout")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The cadence I2C driver calls cdns_i2c_writereg(..) to setup a workaround
in the controller, but did so after calling i2c_add_adapter() which starts
probing devices on the bus. Change the order so that the configuration is
completely finished before using the adapter.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull arm64 fix from Catalin Marinas:
"Fix kernel panic on ACPI-based systems where CPU capacity description
is not currently handled"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: skip register_cpufreq_notifier on ACPI-based systems
write-back cache in degraded mode introduces corner cases to the array.
Although we try to cover all these corner cases, it is safer to just
disable write-back cache when the array is in degraded mode.
In this patch, we disable writeback cache for degraded mode:
1. On device failure, if the array enters degraded mode, raid5_error()
will submit async job r5c_disable_writeback_async to disable
writeback;
2. In r5c_journal_mode_store(), it is invalid to enable writeback in
degraded mode;
3. In r5c_try_caching_write(), stripes with s->failed>0 will be handled
in write-through mode.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Lock sequence IDs are bumped in decode_lock by calling
nfs_increment_seqid(). nfs_increment_sequid() does not use the
seqid_mutating_err() function fixed in commit 059aa7348241 ("Don't
increment lock sequence ID after NFS4ERR_MOVED").
Fixes: 059aa7348241 ("Don't increment lock sequence ID after ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Xuan Qi <xuan.qi@oracle.com>
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
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