linux.git, branch v4.9.9

Linux 4.9.9

2017-02-09T07:08:40+00:00

drm/i915/execlists: Reset RING registers upon resume

2017-02-09T07:08:31+00:00

commit bafb2f7d4755bf1571bd5e9a03b97f3fc4fe69ae upstream.

There is a disparity in the context image saved to disk and our own
bookkeeping - that is we presume the RING_HEAD and RING_TAIL match our
stored ce->ring->tail value. However, as we emit WA_TAIL_DWORDS into the
ring but may not tell the GPU about them, the GPU may be lagging behind
our bookkeeping. Upon hibernation we do not save stolen pages, presuming
that their contents are volatile. This means that although we start
writing into the ring at tail, the GPU starts executing from its HEAD
and there may be some garbage in between and so the GPU promptly hangs
upon resume.

Testcase: igt/gem_exec_suspend/basic-S4
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96526
Signed-off-by: Chris Wilson 
Reviewed-by: Joonas Lahtinen 
Link: http://patchwork.freedesktop.org/patch/msgid/20160921135108.29574-3-chris@chris-wilson.co.uk
Cc: Eric Blau 
Signed-off-by: Greg Kroah-Hartman

fs: break out of iomap_file_buffered_write on fatal signals

2017-02-09T07:08:31+00:00

commit d1908f52557b3230fbd63c0429f3b4b748bf2b6d upstream.

Tetsuo has noticed that an OOM stress test which performs large write
requests can cause the full memory reserves depletion.  He has tracked
this down to the following path

	__alloc_pages_nodemask+0x436/0x4d0
	alloc_pages_current+0x97/0x1b0
	__page_cache_alloc+0x15d/0x1a0          mm/filemap.c:728
	pagecache_get_page+0x5a/0x2b0           mm/filemap.c:1331
	grab_cache_page_write_begin+0x23/0x40   mm/filemap.c:2773
	iomap_write_begin+0x50/0xd0             fs/iomap.c:118
	iomap_write_actor+0xb5/0x1a0            fs/iomap.c:190
	? iomap_write_end+0x80/0x80             fs/iomap.c:150
	iomap_apply+0xb3/0x130                  fs/iomap.c:79
	iomap_file_buffered_write+0x68/0xa0     fs/iomap.c:243
	? iomap_write_end+0x80/0x80
	xfs_file_buffered_aio_write+0x132/0x390 [xfs]
	? remove_wait_queue+0x59/0x60
	xfs_file_write_iter+0x90/0x130 [xfs]
	__vfs_write+0xe5/0x140
	vfs_write+0xc7/0x1f0
	? syscall_trace_enter+0x1d0/0x380
	SyS_write+0x58/0xc0
	do_syscall_64+0x6c/0x200
	entry_SYSCALL64_slow_path+0x25/0x25

the oom victim has access to all memory reserves to make a forward
progress to exit easier.  But iomap_file_buffered_write and other
callers of iomap_apply loop to complete the full request.  We need to
check for fatal signals and back off with a short write instead.

As the iomap_apply delegates all the work down to the actor we have to
hook into those.  All callers that work with the page cache are calling
iomap_write_begin so we will check for signals there.  dax_iomap_actor
has to handle the situation explicitly because it copies data to the
userspace directly.  Other callers like iomap_page_mkwrite work on a
single page or iomap_fiemap_actor do not allocate memory based on the
given len.

Fixes: 68a9f5e7007c ("xfs: implement iomap based buffered write path")
Link: http://lkml.kernel.org/r/20170201092706.9966-2-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Reported-by: Tetsuo Handa 
Reviewed-by: Christoph Hellwig 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

iw_cxgb4: set correct FetchBurstMax for QPs

2017-02-09T07:08:31+00:00

commit b414fa01c31318383ae29d9d23cb9ca4184bbd86 upstream.

The current QP FetchBurstMax value is 256B, which
is incorrect since a WR can exceed that value.  The
result being a partial WR fetched by hardware, and
a fatal "bad WR" error posted by the SGE.

So bump the FetchBurstMax to 512B.

Signed-off-by: Steve Wise 
Signed-off-by: Doug Ledford 
Signed-off-by: Greg Kroah-Hartman

x86/irq: Make irq activate operations symmetric

2017-02-09T07:08:31+00:00

commit aaaec6fc755447a1d056765b11b24d8ff2b81366 upstream.

The recent commit which prevents double activation of interrupts unearthed
interesting code in x86. The code (ab)uses irq_domain_activate_irq() to
reconfigure an already activated interrupt. That trips over the prevention
code now.

Fix it by deactivating the interrupt before activating the new configuration.

Fixes: 08d85f3ea99f1 "irqdomain: Avoid activating interrupts more than once"
Reported-and-tested-by: Mike Galbraith 
Reported-and-tested-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Cc: Andrey Ryabinin 
Cc: Marc Zyngier 
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701311901580.3457@nanos
Signed-off-by: Greg Kroah-Hartman

irqdomain: Avoid activating interrupts more than once

2017-02-09T07:08:31+00:00

commit 08d85f3ea99f1eeafc4e8507936190e86a16ee8c upstream.

Since commit f3b0946d629c ("genirq/msi: Make sure PCI MSIs are
activated early"), we can end-up activating a PCI/MSI twice (once
at allocation time, and once at startup time).

This is normally of no consequences, except that there is some
HW out there that may misbehave if activate is used more than once
(the GICv3 ITS, for example, uses the activate callback
to issue the MAPVI command, and the architecture spec says that
"If there is an existing mapping for the EventID-DeviceID
combination, behavior is UNPREDICTABLE").

While this could be worked around in each individual driver, it may
make more sense to tackle the issue at the core level. In order to
avoid getting in that situation, let's have a per-interrupt flag
to remember if we have already activated that interrupt or not.

Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early")
Reported-and-tested-by: Andre Przywara 
Signed-off-by: Marc Zyngier 
Link: http://lkml.kernel.org/r/1484668848-24361-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

iio: health: max30100: fixed parenthesis around FIFO count check

2017-02-09T07:08:30+00:00

commit 828f84ee8f84710ea1818b3565add268bcb824c8 upstream.

FIFO was being read every sample after the "almost full" state was
reached. This was due to an incorrect placement of the parenthesis
in the while condition check.

Note - the fixes tag is not actually correct, but the fix in this patch
would also be needed for it to function correctly so we'll go with that
one.  Backports should pick up both.

Signed-off-by: Matt Ranostay 
Fixes: b74fccad7 ("iio: health: max30100: correct FIFO check condition")
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman

iio: dht11: Use usleep_range instead of msleep for start signal

2017-02-09T07:08:30+00:00

commit 5c113b5e0082e90d2e1c7b12e96a7b8cf0623e27 upstream.

The DHT22 (AM2302) datasheet specifies that the LOW start pulse should not
exceed 20ms. However, observations with an oscilloscope of an RPi Model 2B
(rev 1.1) communicating with a DHT22 sensor showed that the driver was
consistently sending start pulses longer than 20ms:

Kernel 4.7.10-v7+ (n=132):
    Minimum pulse length: 20.20ms
    Maximum:              29.84ms
    Mean:                 24.96ms
    StDev:                2.82ms
    Sensor response rate: 100%
    Read success rate:    76%

On kernel 4.8, the start pulse was so long that the sensor would not even
respond 97% of the time:

Kernel 4.8.16-v7+ (n=100):
    Minimum pulse length: 30.4ms
    Maximum:              74.4ms
    Mean:                 39.3ms
    StDev:                10.2ms
    Sensor response rate: 3%
    Read success rate:    3%

The driver would return ETIMEDOUT and write log messages like this:

[   51.430987] dht11 dht11@0: Only 1 signal edges detected
[   66.311019] dht11 dht11@0: Only 0 signal edges detected

Replacing msleep(18) with usleep_range(18000, 20000) made the pulse length
sane again and restored responsiveness:

Kernel 4.8.16-v7+ with usleep_range (n=123):
    Minimum pulse length: 18.16ms
    Maximum:              20.20ms
    Mean:                 19.85ms
    StDev:                0.51ms
    Sensor response rate: 100%
    Read success rate:    84%

Signed-off-by: John Brooks 
Reviewed-by: Harald Geyer 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman

iio: health: afe4403: retrieve a valid iio_dev in suspend/resume

2017-02-09T07:08:30+00:00

commit a5badd1e97e6caeca78ad74191f12fc923c403a8 upstream.

The suspend/resume functions were using dev_to_iio_dev() to get
the iio_dev. That only works on IIO dev's.  Replace it with spi
functions to get the correct iio_dev.

Signed-off-by: Alison Schofield 
Acked-by: Andrew F. Davis 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman

iio: health: afe4404: retrieve a valid iio_dev in suspend/resume

2017-02-09T07:08:30+00:00

commit 802ecfc113df1e15af1d028427cbbe785ae9cc4a upstream.

The suspend/resume functions were using dev_to_iio_dev() to get
the iio_dev. That only works on IIO dev's.  Replace it with i2c
functions to get the correct iio_dev.

Signed-off-by: Alison Schofield 
Acked-by: Andrew F. Davis 
Signed-off-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman