<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/gpu/drm, branch v4.19.71</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>drm/i915: Call dma_set_max_seg_size() in i915_driver_hw_probe()</title>
<updated>2019-09-06T08:22:20+00:00</updated>
<author>
<name>Lyude Paul</name>
<email>lyude@redhat.com</email>
</author>
<published>2019-08-23T20:52:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=68b58d3924645356415ae4f6922da8fa14ea1642'/>
<id>68b58d3924645356415ae4f6922da8fa14ea1642</id>
<content type='text'>
commit 32f0a982650b123bdab36865617d3e03ebcacf3b upstream.

Currently, we don't call dma_set_max_seg_size() for i915 because we
intentionally do not limit the segment length that the device supports.
However, this results in a warning being emitted if we try to map
anything larger than SZ_64K on a kernel with CONFIG_DMA_API_DEBUG_SG
enabled:

[    7.751926] DMA-API: i915 0000:00:02.0: mapping sg segment longer
than device claims to support [len=98304] [max=65536]
[    7.751934] WARNING: CPU: 5 PID: 474 at kernel/dma/debug.c:1220
debug_dma_map_sg+0x20f/0x340

This was originally brought up on
https://bugs.freedesktop.org/show_bug.cgi?id=108517 , and the consensus
there was it wasn't really useful to set a limit (and that dma-debug
isn't really all that useful for i915 in the first place). Unfortunately
though, CONFIG_DMA_API_DEBUG_SG is enabled in the debug configs for
various distro kernels. Since a WARN_ON() will disable automatic problem
reporting (and cause any CI with said option enabled to start
complaining), we really should just fix the problem.

Note that as me and Chris Wilson discussed, the other solution for this
would be to make DMA-API not make such assumptions when a driver hasn't
explicitly set a maximum segment size. But, taking a look at the commit
which originally introduced this behavior, commit 78c47830a5cb
("dma-debug: check scatterlist segments"), there is an explicit mention
of this assumption and how it applies to devices with no segment size:

	Conversely, devices which are less limited than the rather
	conservative defaults, or indeed have no limitations at all
	(e.g. GPUs with their own internal MMU), should be encouraged to
	set appropriate dma_parms, as they may get more efficient DMA
	mapping performance out of it.

So unless there's any concerns (I'm open to discussion!), let's just
follow suite and call dma_set_max_seg_size() with UINT_MAX as our limit
to silence any warnings.

Changes since v3:
* Drop patch for enabling CONFIG_DMA_API_DEBUG_SG in CI. It looks like
  just turning it on causes the kernel to spit out bogus WARN_ONs()
  during some igt tests which would otherwise require teaching igt to
  disable the various DMA-API debugging options causing this. This is
  too much work to be worth it, since DMA-API debugging is useless for
  us. So, we'll just settle with this single patch to squelch WARN_ONs()
  during driver load for users that have CONFIG_DMA_API_DEBUG_SG turned
  on for some reason.
* Move dma_set_max_seg_size() call into i915_driver_hw_probe() - Chris
  Wilson

Signed-off-by: Lyude Paul &lt;lyude@redhat.com&gt;
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v4.18+
Link: https://patchwork.freedesktop.org/patch/msgid/20190823205251.14298-1-lyude@redhat.com
(cherry picked from commit acd674af95d3f627062007429b9c195c6b32361d)
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 32f0a982650b123bdab36865617d3e03ebcacf3b upstream.

Currently, we don't call dma_set_max_seg_size() for i915 because we
intentionally do not limit the segment length that the device supports.
However, this results in a warning being emitted if we try to map
anything larger than SZ_64K on a kernel with CONFIG_DMA_API_DEBUG_SG
enabled:

[    7.751926] DMA-API: i915 0000:00:02.0: mapping sg segment longer
than device claims to support [len=98304] [max=65536]
[    7.751934] WARNING: CPU: 5 PID: 474 at kernel/dma/debug.c:1220
debug_dma_map_sg+0x20f/0x340

This was originally brought up on
https://bugs.freedesktop.org/show_bug.cgi?id=108517 , and the consensus
there was it wasn't really useful to set a limit (and that dma-debug
isn't really all that useful for i915 in the first place). Unfortunately
though, CONFIG_DMA_API_DEBUG_SG is enabled in the debug configs for
various distro kernels. Since a WARN_ON() will disable automatic problem
reporting (and cause any CI with said option enabled to start
complaining), we really should just fix the problem.

Note that as me and Chris Wilson discussed, the other solution for this
would be to make DMA-API not make such assumptions when a driver hasn't
explicitly set a maximum segment size. But, taking a look at the commit
which originally introduced this behavior, commit 78c47830a5cb
("dma-debug: check scatterlist segments"), there is an explicit mention
of this assumption and how it applies to devices with no segment size:

	Conversely, devices which are less limited than the rather
	conservative defaults, or indeed have no limitations at all
	(e.g. GPUs with their own internal MMU), should be encouraged to
	set appropriate dma_parms, as they may get more efficient DMA
	mapping performance out of it.

So unless there's any concerns (I'm open to discussion!), let's just
follow suite and call dma_set_max_seg_size() with UINT_MAX as our limit
to silence any warnings.

Changes since v3:
* Drop patch for enabling CONFIG_DMA_API_DEBUG_SG in CI. It looks like
  just turning it on causes the kernel to spit out bogus WARN_ONs()
  during some igt tests which would otherwise require teaching igt to
  disable the various DMA-API debugging options causing this. This is
  too much work to be worth it, since DMA-API debugging is useless for
  us. So, we'll just settle with this single patch to squelch WARN_ONs()
  during driver load for users that have CONFIG_DMA_API_DEBUG_SG turned
  on for some reason.
* Move dma_set_max_seg_size() call into i915_driver_hw_probe() - Chris
  Wilson

Signed-off-by: Lyude Paul &lt;lyude@redhat.com&gt;
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v4.18+
Link: https://patchwork.freedesktop.org/patch/msgid/20190823205251.14298-1-lyude@redhat.com
(cherry picked from commit acd674af95d3f627062007429b9c195c6b32361d)
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: Don't deballoon unused ggtt drm_mm_node in linux guest</title>
<updated>2019-09-06T08:22:20+00:00</updated>
<author>
<name>Xiong Zhang</name>
<email>xiong.y.zhang@intel.com</email>
</author>
<published>2019-08-20T05:46:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c7615333645de572cae573da0a92dd3fc8e099e0'/>
<id>c7615333645de572cae573da0a92dd3fc8e099e0</id>
<content type='text'>
commit 0a3dfbb5cd9033752639ef33e319c2f2863c713a upstream.

The following call trace may exist in linux guest dmesg when guest i915
driver is unloaded.
[   90.776610] [drm:vgt_deballoon_space.isra.0 [i915]] deballoon space: range [0x0 - 0x0] 0 KiB.
[   90.776621] BUG: unable to handle kernel NULL pointer dereference at 00000000000000c0
[   90.776691] IP: drm_mm_remove_node+0x4d/0x320 [drm]
[   90.776718] PGD 800000012c7d0067 P4D 800000012c7d0067 PUD 138e4c067 PMD 0
[   90.777091] task: ffff9adab60f2f00 task.stack: ffffaf39c0fe0000
[   90.777142] RIP: 0010:drm_mm_remove_node+0x4d/0x320 [drm]
[   90.777573] Call Trace:
[   90.777653]  intel_vgt_deballoon+0x4c/0x60 [i915]
[   90.777729]  i915_ggtt_cleanup_hw+0x121/0x190 [i915]
[   90.777792]  i915_driver_unload+0x145/0x180 [i915]
[   90.777856]  i915_pci_remove+0x15/0x20 [i915]
[   90.777890]  pci_device_remove+0x3b/0xc0
[   90.777916]  device_release_driver_internal+0x157/0x220
[   90.777945]  driver_detach+0x39/0x70
[   90.777967]  bus_remove_driver+0x51/0xd0
[   90.777990]  pci_unregister_driver+0x23/0x90
[   90.778019]  SyS_delete_module+0x1da/0x240
[   90.778045]  entry_SYSCALL_64_fastpath+0x24/0x87
[   90.778072] RIP: 0033:0x7f34312af067
[   90.778092] RSP: 002b:00007ffdea3da0d8 EFLAGS: 00000206
[   90.778297] RIP: drm_mm_remove_node+0x4d/0x320 [drm] RSP: ffffaf39c0fe3dc0
[   90.778344] ---[ end trace f4b1bc8305fc59dd ]---

Four drm_mm_node are used to reserve guest ggtt space, but some of them
may be skipped and not initialised due to space constraints in
intel_vgt_balloon(). If drm_mm_remove_node() is called with
uninitialized drm_mm_node, the above call trace occurs.

This patch check drm_mm_node's validity before calling
drm_mm_remove_node().

Fixes: ff8f797557c7("drm/i915: return the correct usable aperture size under gvt environment")
Cc: stable@vger.kernel.org
Signed-off-by: Xiong Zhang &lt;xiong.y.zhang@intel.com&gt;
Acked-by: Zhenyu Wang &lt;zhenyuw@linux.intel.com&gt;
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Signed-off-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1566279978-9659-1-git-send-email-xiong.y.zhang@intel.com
(cherry picked from commit 4776f3529d6b1e47f02904ad1d264d25ea22b27b)
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0a3dfbb5cd9033752639ef33e319c2f2863c713a upstream.

The following call trace may exist in linux guest dmesg when guest i915
driver is unloaded.
[   90.776610] [drm:vgt_deballoon_space.isra.0 [i915]] deballoon space: range [0x0 - 0x0] 0 KiB.
[   90.776621] BUG: unable to handle kernel NULL pointer dereference at 00000000000000c0
[   90.776691] IP: drm_mm_remove_node+0x4d/0x320 [drm]
[   90.776718] PGD 800000012c7d0067 P4D 800000012c7d0067 PUD 138e4c067 PMD 0
[   90.777091] task: ffff9adab60f2f00 task.stack: ffffaf39c0fe0000
[   90.777142] RIP: 0010:drm_mm_remove_node+0x4d/0x320 [drm]
[   90.777573] Call Trace:
[   90.777653]  intel_vgt_deballoon+0x4c/0x60 [i915]
[   90.777729]  i915_ggtt_cleanup_hw+0x121/0x190 [i915]
[   90.777792]  i915_driver_unload+0x145/0x180 [i915]
[   90.777856]  i915_pci_remove+0x15/0x20 [i915]
[   90.777890]  pci_device_remove+0x3b/0xc0
[   90.777916]  device_release_driver_internal+0x157/0x220
[   90.777945]  driver_detach+0x39/0x70
[   90.777967]  bus_remove_driver+0x51/0xd0
[   90.777990]  pci_unregister_driver+0x23/0x90
[   90.778019]  SyS_delete_module+0x1da/0x240
[   90.778045]  entry_SYSCALL_64_fastpath+0x24/0x87
[   90.778072] RIP: 0033:0x7f34312af067
[   90.778092] RSP: 002b:00007ffdea3da0d8 EFLAGS: 00000206
[   90.778297] RIP: drm_mm_remove_node+0x4d/0x320 [drm] RSP: ffffaf39c0fe3dc0
[   90.778344] ---[ end trace f4b1bc8305fc59dd ]---

Four drm_mm_node are used to reserve guest ggtt space, but some of them
may be skipped and not initialised due to space constraints in
intel_vgt_balloon(). If drm_mm_remove_node() is called with
uninitialized drm_mm_node, the above call trace occurs.

This patch check drm_mm_node's validity before calling
drm_mm_remove_node().

Fixes: ff8f797557c7("drm/i915: return the correct usable aperture size under gvt environment")
Cc: stable@vger.kernel.org
Signed-off-by: Xiong Zhang &lt;xiong.y.zhang@intel.com&gt;
Acked-by: Zhenyu Wang &lt;zhenyuw@linux.intel.com&gt;
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Signed-off-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1566279978-9659-1-git-send-email-xiong.y.zhang@intel.com
(cherry picked from commit 4776f3529d6b1e47f02904ad1d264d25ea22b27b)
Signed-off-by: Jani Nikula &lt;jani.nikula@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/amdgpu: Add APTX quirk for Dell Latitude 5495</title>
<updated>2019-09-06T08:22:19+00:00</updated>
<author>
<name>Kai-Heng Feng</name>
<email>kai.heng.feng@canonical.com</email>
</author>
<published>2019-08-27T09:33:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6d3003f56449756ad5bcdd2994a0d7262e84da99'/>
<id>6d3003f56449756ad5bcdd2994a0d7262e84da99</id>
<content type='text'>
commit 317a3aaef94d73ba6be88aea11b41bb631b2d581 upstream.

Needs ATPX rather than _PR3 to really turn off the dGPU. This can save
~5W when dGPU is runtime-suspended.

Signed-off-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Signed-off-by: Alex Deucher &lt;alexander.deucher@amd.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 317a3aaef94d73ba6be88aea11b41bb631b2d581 upstream.

Needs ATPX rather than _PR3 to really turn off the dGPU. This can save
~5W when dGPU is runtime-suspended.

Signed-off-by: Kai-Heng Feng &lt;kai.heng.feng@canonical.com&gt;
Signed-off-by: Alex Deucher &lt;alexander.deucher@amd.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/tilcdc: Register cpufreq notifier after we have initialized crtc</title>
<updated>2019-09-06T08:22:03+00:00</updated>
<author>
<name>Jyri Sarha</name>
<email>jsarha@ti.com</email>
</author>
<published>2018-12-12T17:26:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dc066fd0d0737b0e4263775951789c9aa765a8c3'/>
<id>dc066fd0d0737b0e4263775951789c9aa765a8c3</id>
<content type='text'>
[ Upstream commit 432973fd3a20102840d5f7e61af9f1a03c217a4c ]

Register cpufreq notifier after we have initialized the crtc and
unregister it before we remove the ctrc. Receiving a cpufreq notify
without crtc causes a crash.

Reported-by: Peter Ujfalusi &lt;peter.ujfalusi@ti.com&gt;
Signed-off-by: Jyri Sarha &lt;jsarha@ti.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 432973fd3a20102840d5f7e61af9f1a03c217a4c ]

Register cpufreq notifier after we have initialized the crtc and
unregister it before we remove the ctrc. Receiving a cpufreq notify
without crtc causes a crash.

Reported-by: Peter Ujfalusi &lt;peter.ujfalusi@ti.com&gt;
Signed-off-by: Jyri Sarha &lt;jsarha@ti.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/bridge: tfp410: fix memleak in get_modes()</title>
<updated>2019-09-06T08:22:02+00:00</updated>
<author>
<name>Tomi Valkeinen</name>
<email>tomi.valkeinen@ti.com</email>
</author>
<published>2019-06-10T13:57:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=edd40f54736d716ad4e40aa6f18b0a1b79051f70'/>
<id>edd40f54736d716ad4e40aa6f18b0a1b79051f70</id>
<content type='text'>
[ Upstream commit c08f99c39083ab55a9c93b3e93cef48711294dad ]

We don't free the edid blob allocated by the call to drm_get_edid(),
causing a memleak. Fix this by calling kfree(edid) at the end of the
get_modes().

Signed-off-by: Tomi Valkeinen &lt;tomi.valkeinen@ti.com&gt;
Signed-off-by: Andrzej Hajda &lt;a.hajda@samsung.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190610135739.6077-1-tomi.valkeinen@ti.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c08f99c39083ab55a9c93b3e93cef48711294dad ]

We don't free the edid blob allocated by the call to drm_get_edid(),
causing a memleak. Fix this by calling kfree(edid) at the end of the
get_modes().

Signed-off-by: Tomi Valkeinen &lt;tomi.valkeinen@ti.com&gt;
Signed-off-by: Andrzej Hajda &lt;a.hajda@samsung.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190610135739.6077-1-tomi.valkeinen@ti.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915: fix broadwell EU computation</title>
<updated>2019-09-06T08:22:01+00:00</updated>
<author>
<name>Lionel Landwerlin</name>
<email>lionel.g.landwerlin@intel.com</email>
</author>
<published>2018-11-12T12:39:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a3eb2eba2f79950b788342562604d36c5a260da7'/>
<id>a3eb2eba2f79950b788342562604d36c5a260da7</id>
<content type='text'>
[ Upstream commit 63ac3328f0d1d37f286e397b14d9596ed09d7ca5 ]

subslice_mask is an array indexed by slice, not subslice.

Signed-off-by: Lionel Landwerlin &lt;lionel.g.landwerlin@intel.com&gt;
Fixes: 8cc7669355136f ("drm/i915: store all subslice masks")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108712
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Reviewed-by: Tvrtko Ursulin &lt;tvrtko.ursulin@intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20181112123931.2815-1-lionel.g.landwerlin@intel.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 63ac3328f0d1d37f286e397b14d9596ed09d7ca5 ]

subslice_mask is an array indexed by slice, not subslice.

Signed-off-by: Lionel Landwerlin &lt;lionel.g.landwerlin@intel.com&gt;
Fixes: 8cc7669355136f ("drm/i915: store all subslice masks")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108712
Reviewed-by: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Reviewed-by: Tvrtko Ursulin &lt;tvrtko.ursulin@intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20181112123931.2815-1-lionel.g.landwerlin@intel.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/ast: Fixed reboot test may cause system hanged</title>
<updated>2019-09-06T08:21:59+00:00</updated>
<author>
<name>Y.C. Chen</name>
<email>yc_chen@aspeedtech.com</email>
</author>
<published>2018-04-11T01:27:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=37654abed26f77429c23de4d777842320c95945c'/>
<id>37654abed26f77429c23de4d777842320c95945c</id>
<content type='text'>
[ Upstream commit 05b439711f6ff8700e8660f97a1179650778b9cb ]

There is another thread still access standard VGA I/O while loading drm driver.
Disable standard VGA I/O decode to avoid this issue.

Signed-off-by: Y.C. Chen &lt;yc_chen@aspeedtech.com&gt;
Reviewed-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Dave Airlie &lt;airlied@redhat.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1523410059-18415-1-git-send-email-yc_chen@aspeedtech.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 05b439711f6ff8700e8660f97a1179650778b9cb ]

There is another thread still access standard VGA I/O while loading drm driver.
Disable standard VGA I/O decode to avoid this issue.

Signed-off-by: Y.C. Chen &lt;yc_chen@aspeedtech.com&gt;
Reviewed-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Dave Airlie &lt;airlied@redhat.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1523410059-18415-1-git-send-email-yc_chen@aspeedtech.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/nouveau: Don't retry infinitely when receiving no data on i2c over AUX</title>
<updated>2019-08-29T06:28:51+00:00</updated>
<author>
<name>Lyude Paul</name>
<email>lyude@redhat.com</email>
</author>
<published>2019-07-25T19:40:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f88c31b43babfab3bcd85d18aede278455f0776d'/>
<id>f88c31b43babfab3bcd85d18aede278455f0776d</id>
<content type='text'>
commit c358ebf59634f06d8ed176da651ec150df3c8686 upstream.

While I had thought I had fixed this issue in:

commit 342406e4fbba ("drm/nouveau/i2c: Disable i2c bus access after
-&gt;fini()")

It turns out that while I did fix the error messages I was seeing on my
P50 when trying to access i2c busses with the GPU in runtime suspend, I
accidentally had missed one important detail that was mentioned on the
bug report this commit was supposed to fix: that the CPU would only lock
up when trying to access i2c busses _on connected devices_ _while the
GPU is not in runtime suspend_. Whoops. That definitely explains why I
was not able to get my machine to hang with i2c bus interactions until
now, as plugging my P50 into it's dock with an HDMI monitor connected
allowed me to finally reproduce this locally.

Now that I have managed to reproduce this issue properly, it looks like
the problem is much simpler then it looks. It turns out that some
connected devices, such as MST laptop docks, will actually ACK i2c reads
even if no data was actually read:

[  275.063043] nouveau 0000:01:00.0: i2c: aux 000a: 1: 0000004c 1
[  275.063447] nouveau 0000:01:00.0: i2c: aux 000a: 00 01101000 10040000
[  275.063759] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000001
[  275.064024] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000000
[  275.064285] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000000
[  275.064594] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000000

Because we don't handle the situation of i2c ack without any data, we
end up entering an infinite loop in nvkm_i2c_aux_i2c_xfer() since the
value of cnt always remains at 0. This finally properly explains how
this could result in a CPU hang like the ones observed in the
aforementioned commit.

So, fix this by retrying transactions if no data is written or received,
and give up and fail the transaction if we continue to not write or
receive any data after 32 retries.

Signed-off-by: Lyude Paul &lt;lyude@redhat.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs &lt;bskeggs@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c358ebf59634f06d8ed176da651ec150df3c8686 upstream.

While I had thought I had fixed this issue in:

commit 342406e4fbba ("drm/nouveau/i2c: Disable i2c bus access after
-&gt;fini()")

It turns out that while I did fix the error messages I was seeing on my
P50 when trying to access i2c busses with the GPU in runtime suspend, I
accidentally had missed one important detail that was mentioned on the
bug report this commit was supposed to fix: that the CPU would only lock
up when trying to access i2c busses _on connected devices_ _while the
GPU is not in runtime suspend_. Whoops. That definitely explains why I
was not able to get my machine to hang with i2c bus interactions until
now, as plugging my P50 into it's dock with an HDMI monitor connected
allowed me to finally reproduce this locally.

Now that I have managed to reproduce this issue properly, it looks like
the problem is much simpler then it looks. It turns out that some
connected devices, such as MST laptop docks, will actually ACK i2c reads
even if no data was actually read:

[  275.063043] nouveau 0000:01:00.0: i2c: aux 000a: 1: 0000004c 1
[  275.063447] nouveau 0000:01:00.0: i2c: aux 000a: 00 01101000 10040000
[  275.063759] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000001
[  275.064024] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000000
[  275.064285] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000000
[  275.064594] nouveau 0000:01:00.0: i2c: aux 000a: rd 00000000

Because we don't handle the situation of i2c ack without any data, we
end up entering an infinite loop in nvkm_i2c_aux_i2c_xfer() since the
value of cnt always remains at 0. This finally properly explains how
this could result in a CPU hang like the ones observed in the
aforementioned commit.

So, fix this by retrying transactions if no data is written or received,
and give up and fail the transaction if we continue to not write or
receive any data after 32 retries.

Signed-off-by: Lyude Paul &lt;lyude@redhat.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs &lt;bskeggs@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>drm/vmwgfx: fix memory leak when too many retries have occurred</title>
<updated>2019-08-29T06:28:46+00:00</updated>
<author>
<name>Colin Ian King</name>
<email>colin.king@canonical.com</email>
</author>
<published>2019-06-24T16:39:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa6f4687805a38af3dd27cd02445daa806736335'/>
<id>fa6f4687805a38af3dd27cd02445daa806736335</id>
<content type='text'>
[ Upstream commit 6b7c3b86f0b63134b2ab56508921a0853ffa687a ]

Currently when too many retries have occurred there is a memory
leak on the allocation for reply on the error return path. Fix
this by kfree'ing reply before returning.

Addresses-Coverity: ("Resource leak")
Fixes: a9cd9c044aa9 ("drm/vmwgfx: Add a check to handle host message failure")
Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Reviewed-by: Deepak Rawat &lt;drawat@vmware.com&gt;
Signed-off-by: Deepak Rawat &lt;drawat@vmware.com&gt;
Signed-off-by: Thomas Hellstrom &lt;thellstrom@vmware.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6b7c3b86f0b63134b2ab56508921a0853ffa687a ]

Currently when too many retries have occurred there is a memory
leak on the allocation for reply on the error return path. Fix
this by kfree'ing reply before returning.

Addresses-Coverity: ("Resource leak")
Fixes: a9cd9c044aa9 ("drm/vmwgfx: Add a check to handle host message failure")
Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Reviewed-by: Deepak Rawat &lt;drawat@vmware.com&gt;
Signed-off-by: Deepak Rawat &lt;drawat@vmware.com&gt;
Signed-off-by: Thomas Hellstrom &lt;thellstrom@vmware.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/rockchip: Suspend DP late</title>
<updated>2019-08-29T06:28:40+00:00</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2019-08-02T18:46:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6cb4997861c8bf9a73b54b123c02fab436b852a6'/>
<id>6cb4997861c8bf9a73b54b123c02fab436b852a6</id>
<content type='text'>
[ Upstream commit f7ccbed656f78212593ca965d9a8f34bf24e0aab ]

In commit fe64ba5c6323 ("drm/rockchip: Resume DP early") we moved
resume to be early but left suspend at its normal time.  This seems
like it could be OK, but casues problems if a suspend gets interrupted
partway through.  The OS only balances matching suspend/resume levels.
...so if suspend was called then resume will be called.  If suspend
late was called then resume early will be called.  ...but if suspend
was called resume early might not get called.  This leads to an
unbalance in the clock enables / disables.

Lets take the simple fix and just move suspend to be late to match.
This makes the PM core take proper care in keeping things balanced.

Fixes: fe64ba5c6323 ("drm/rockchip: Resume DP early")
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Signed-off-by: Sean Paul &lt;seanpaul@chromium.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190802184616.44822-1-dianders@chromium.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f7ccbed656f78212593ca965d9a8f34bf24e0aab ]

In commit fe64ba5c6323 ("drm/rockchip: Resume DP early") we moved
resume to be early but left suspend at its normal time.  This seems
like it could be OK, but casues problems if a suspend gets interrupted
partway through.  The OS only balances matching suspend/resume levels.
...so if suspend was called then resume will be called.  If suspend
late was called then resume early will be called.  ...but if suspend
was called resume early might not get called.  This leads to an
unbalance in the clock enables / disables.

Lets take the simple fix and just move suspend to be late to match.
This makes the PM core take proper care in keeping things balanced.

Fixes: fe64ba5c6323 ("drm/rockchip: Resume DP early")
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Signed-off-by: Sean Paul &lt;seanpaul@chromium.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190802184616.44822-1-dianders@chromium.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
