<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/include/drm, branch v6.6.14</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.14</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.14'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2024-01-25T23:35:32+00:00</updated>
<entry>
<title>drm/bridge: Fix typo in post_disable() description</title>
<updated>2024-01-25T23:35:32+00:00</updated>
<author>
<name>Dario Binacchi</name>
<email>dario.binacchi@amarulasolutions.com</email>
</author>
<published>2023-11-24T09:42:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c111350d673a517c3995849c724e444205f7e51c'/>
<id>urn:sha1:c111350d673a517c3995849c724e444205f7e51c</id>
<content type='text'>
[ Upstream commit 288b039db225676e0c520c981a1b5a2562d893a3 ]

s/singals/signals/

Fixes: 199e4e967af4 ("drm: Extract drm_bridge.h")
Signed-off-by: Dario Binacchi &lt;dario.binacchi@amarulasolutions.com&gt;
Signed-off-by: Robert Foss &lt;rfoss@kernel.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20231124094253.658064-1-dario.binacchi@amarulasolutions.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/dp_mst: Fix fractional DSC bpp handling</title>
<updated>2024-01-25T23:35:31+00:00</updated>
<author>
<name>Ville Syrjälä</name>
<email>ville.syrjala@linux.intel.com</email>
</author>
<published>2023-10-24T01:08:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4e042f022255604c68ab5d5f73c8f437d24d651e'/>
<id>urn:sha1:4e042f022255604c68ab5d5f73c8f437d24d651e</id>
<content type='text'>
[ Upstream commit 7707dd6022593f3edd8e182e7935870cf326f874 ]

The current code does '(bpp &lt;&lt; 4) / 16' in the MST PBN
calculation, but that is just the same as 'bpp' so the
DSC codepath achieves absolutely nothing. Fix it up so that
the fractional part of the bpp value is actually used instead
of truncated away. 64*1006 has enough zero lsbs that we can
just shift that down in the dividend and thus still manage
to stick to a 32bit divisor.

And while touching this, let's just make the whole thing more
straightforward by making the passed in bpp value .4 binary
fixed point always, instead of having to pass in different
things based on whether DSC is enabled or not.

v2:
- Fix DSC kunit test cases.

Cc: Manasi Navare &lt;manasi.d.navare@intel.com&gt;
Cc: Lyude Paul &lt;lyude@redhat.com&gt;
Cc: Harry Wentland &lt;harry.wentland@amd.com&gt;
Cc: David Francis &lt;David.Francis@amd.com&gt;
Cc: Mikita Lipski &lt;mikita.lipski@amd.com&gt;
Cc: Alex Deucher &lt;alexander.deucher@amd.com&gt;
Fixes: dc48529fb14e ("drm/dp_mst: Add PBN calculation for DSC modes")
Signed-off-by: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
[Imre: Fix kunit test cases]
Acked-by: Maxime Ripard &lt;mripard@kernel.org&gt;
Reviewed-by: Lyude Paul &lt;lyude@redhat.com&gt;
Acked-by: Harry Wentland &lt;harry.wentland@amd.com&gt;
Signed-off-by: Imre Deak &lt;imre.deak@intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20231030155843.2251023-3-imre.deak@intel.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Revert "drm/prime: Unexport helpers for fd/handle conversion"</title>
<updated>2024-01-20T10:51:39+00:00</updated>
<author>
<name>Felix Kuehling</name>
<email>Felix.Kuehling@amd.com</email>
</author>
<published>2023-11-17T21:44:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=379af079c42738fa3f33de5912931a7865887c62'/>
<id>urn:sha1:379af079c42738fa3f33de5912931a7865887c62</id>
<content type='text'>
[ Upstream commit 0514f63cfff38a0dcb7ba9c5f245827edc0c5107 ]

This reverts commit 71a7974ac7019afeec105a54447ae1dc7216cbb3.

These helper functions are needed for KFD to export and import DMABufs
the right way without duplicating the tracking of DMABufs associated with
GEM objects while ensuring that move notifier callbacks are working as
intended.

CC: Christian König &lt;christian.koenig@amd.com&gt;
CC: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Acked-by: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Acked-by: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Signed-off-by: Felix Kuehling &lt;Felix.Kuehling@amd.com&gt;
Signed-off-by: Alex Deucher &lt;alexander.deucher@amd.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm: Update file owner during use</title>
<updated>2024-01-01T12:42:25+00:00</updated>
<author>
<name>Tvrtko Ursulin</name>
<email>tvrtko.ursulin@intel.com</email>
</author>
<published>2023-06-21T09:48:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=031ddd28008971cce0b5626379b910d0a05fb4dd'/>
<id>urn:sha1:031ddd28008971cce0b5626379b910d0a05fb4dd</id>
<content type='text'>
[ Upstream commit 1c7a387ffef894b1ab3942f0482dac7a6e0a909c ]

With the typical model where the display server opens the file descriptor
and then hands it over to the client(*), we were showing stale data in
debugfs.

Fix it by updating the drm_file-&gt;pid on ioctl access from a different
process.

The field is also made RCU protected to allow for lockless readers. Update
side is protected with dev-&gt;filelist_mutex.

Before:

$ cat /sys/kernel/debug/dri/0/clients
             command   pid dev master a   uid      magic
                Xorg  2344   0   y    y     0          0
                Xorg  2344   0   n    y     0          2
                Xorg  2344   0   n    y     0          3
                Xorg  2344   0   n    y     0          4

After:

$ cat /sys/kernel/debug/dri/0/clients
             command  tgid dev master a   uid      magic
                Xorg   830   0   y    y     0          0
       xfce4-session   880   0   n    y     0          1
               xfwm4   943   0   n    y     0          2
           neverball  1095   0   n    y     0          3

*)
More detailed and historically accurate description of various handover
implementation kindly provided by Emil Velikov:

"""
The traditional model, the server was the orchestrator managing the
primary device node. From the fd, to the master status and
authentication. But looking at the fd alone, this has varied across
the years.

IIRC in the DRI1 days, Xorg (libdrm really) would have a list of open
fd(s) and reuse those whenever needed, DRI2 the client was responsible
for open() themselves and with DRI3 the fd was passed to the client.

Around the inception of DRI3 and systemd-logind, the latter became
another possible orchestrator. Whereby Xorg and Wayland compositors
could ask it for the fd. For various reasons (hysterical and genuine
ones) Xorg has a fallback path going the open(), whereas Wayland
compositors are moving to solely relying on logind... some never had
fallback even.

Over the past few years, more projects have emerged which provide
functionality similar (be that on API level, Dbus, or otherwise) to
systemd-logind.
"""

v2:
 * Fixed typo in commit text and added a fine historical explanation
   from Emil.

Signed-off-by: Tvrtko Ursulin &lt;tvrtko.ursulin@intel.com&gt;
Cc: "Christian König" &lt;christian.koenig@amd.com&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Acked-by: Christian König &lt;christian.koenig@amd.com&gt;
Reviewed-by: Emil Velikov &lt;emil.l.velikov@gmail.com&gt;
Reviewed-by: Rob Clark &lt;robdclark@gmail.com&gt;
Tested-by: Rob Clark &lt;robdclark@gmail.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20230621094824.2348732-1-tvrtko.ursulin@linux.intel.com
Signed-off-by: Christian König &lt;christian.koenig@amd.com&gt;
Stable-dep-of: 5a6c9a05e55c ("drm: Fix FD ownership check in drm_master_check_perm()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/atomic-helpers: Invoke end_fb_access while owning plane state</title>
<updated>2023-12-13T17:45:25+00:00</updated>
<author>
<name>Thomas Zimmermann</name>
<email>tzimmermann@suse.de</email>
</author>
<published>2023-12-04T08:32:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=02650b3b98cff56d26ec3687b76da4a81c20d187'/>
<id>urn:sha1:02650b3b98cff56d26ec3687b76da4a81c20d187</id>
<content type='text'>
commit e0f04e41e8eedd4e5a1275f2318df7e1841855f2 upstream.

Invoke drm_plane_helper_funcs.end_fb_access before
drm_atomic_helper_commit_hw_done(). The latter function hands over
ownership of the plane state to the following commit, which might
free it. Releasing resources in end_fb_access then operates on undefined
state. This bug has been observed with non-blocking commits when they
are being queued up quickly.

Here is an example stack trace from the bug report. The plane state has
been free'd already, so the pages for drm_gem_fb_vunmap() are gone.

Unable to handle kernel paging request at virtual address 0000000100000049
[...]
 drm_gem_fb_vunmap+0x18/0x74
 drm_gem_end_shadow_fb_access+0x1c/0x2c
 drm_atomic_helper_cleanup_planes+0x58/0xd8
 drm_atomic_helper_commit_tail+0x90/0xa0
 commit_tail+0x15c/0x188
 commit_work+0x14/0x20

Fix this by running end_fb_access immediately after updating all planes
in drm_atomic_helper_commit_planes(). The existing clean-up helper
drm_atomic_helper_cleanup_planes() now only handles cleanup_fb.

For aborted commits, roll back from drm_atomic_helper_prepare_planes()
in the new helper drm_atomic_helper_unprepare_planes(). This case is
different from regular cleanup, as we have to release the new state;
regular cleanup releases the old state. The new helper also invokes
cleanup_fb for all planes.

The changes mostly involve DRM's atomic helpers. Only two drivers, i915
and nouveau, implement their own commit function. Update them to invoke
drm_atomic_helper_unprepare_planes(). Drivers with custom commit_tail
function do not require changes.

v4:
	* fix documentation (kernel test robot)
v3:
	* add drm_atomic_helper_unprepare_planes() for rolling back
	* use correct state for end_fb_access
v2:
	* fix test in drm_atomic_helper_cleanup_planes()

Reported-by: Alyssa Ross &lt;hi@alyssa.is&gt;
Closes: https://lore.kernel.org/dri-devel/87leazm0ya.fsf@alyssa.is/
Suggested-by: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Fixes: 94d879eaf7fb ("drm/atomic-helper: Add {begin,end}_fb_access to plane helpers")
Tested-by: Alyssa Ross &lt;hi@alyssa.is&gt;
Reviewed-by: Alyssa Ross &lt;hi@alyssa.is&gt;
Signed-off-by: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.2+
Link: https://patchwork.freedesktop.org/patch/msgid/20231204083247.22006-1-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm: bridge: samsung-dsim: Fix waiting for empty cmd transfer FIFO on older Exynos</title>
<updated>2023-11-20T10:59:08+00:00</updated>
<author>
<name>Marek Szyprowski</name>
<email>m.szyprowski@samsung.com</email>
</author>
<published>2023-08-09T14:56:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2f56a02e2ab0118b553dfc53b05eb65ce760975c'/>
<id>urn:sha1:2f56a02e2ab0118b553dfc53b05eb65ce760975c</id>
<content type='text'>
[ Upstream commit 15f389da11257b806da75a070cfa41ca0cc15aae ]

Samsung DSIM used in older Exynos SoCs (like Exynos 4210, 4x12, 3250)
doesn't report empty level of packer header FIFO. In case of those SoCs,
use the old way of waiting for empty command tranfsfer FIFO, removed
recently by commit 14806c641582 ("drm: bridge: samsung-dsim: Drain command transfer FIFO before transfer").

Fixes: 14806c641582 ("drm: bridge: samsung-dsim: Drain command transfer FIFO before transfer")
Signed-off-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Reviewed-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Robert Foss &lt;rfoss@kernel.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20230809145641.3213210-1-m.szyprowski@samsung.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>gpu/drm: Eliminate DRM_SCHED_PRIORITY_UNSET</title>
<updated>2023-10-18T00:35:38+00:00</updated>
<author>
<name>Luben Tuikov</name>
<email>luben.tuikov@amd.com</email>
</author>
<published>2023-10-17T02:48:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fa8391ad68c16716e2c06ada397e99ceed2fb647'/>
<id>urn:sha1:fa8391ad68c16716e2c06ada397e99ceed2fb647</id>
<content type='text'>
Eliminate DRM_SCHED_PRIORITY_UNSET, value of -2, whose only user was
amdgpu. Furthermore, eliminate an index bug, in that when amdgpu boots, it
calls drm_sched_entity_init() with DRM_SCHED_PRIORITY_UNSET, which uses it to
index sched-&gt;sched_rq[].

Cc: Alex Deucher &lt;Alexander.Deucher@amd.com&gt;
Cc: Christian König &lt;christian.koenig@amd.com&gt;
Signed-off-by: Luben Tuikov &lt;luben.tuikov@amd.com&gt;
Acked-by: Alex Deucher &lt;Alexander.Deucher@amd.com&gt;
Link: https://lore.kernel.org/r/20231017035656.8211-2-luben.tuikov@amd.com
</content>
</entry>
<entry>
<title>drm/tests: helpers: Avoid a driver uaf</title>
<updated>2023-09-14T11:57:58+00:00</updated>
<author>
<name>Thomas Hellström</name>
<email>thomas.hellstrom@linux.intel.com</email>
</author>
<published>2023-09-07T13:53:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=139a27854bf5ce93ff9805f9f7683b88c13074dc'/>
<id>urn:sha1:139a27854bf5ce93ff9805f9f7683b88c13074dc</id>
<content type='text'>
when using __drm_kunit_helper_alloc_drm_device() the driver may be
dereferenced by device-managed resources up until the device is
freed, which is typically later than the kunit-managed resource code
frees it. Fix this by simply make the driver device-managed as well.

In short, the sequence leading to the UAF is as follows:

INIT:
Code allocates a struct device as a kunit-managed resource.
Code allocates a drm driver as a kunit-managed resource.
Code allocates a drm device as a device-managed resource.

EXIT:
Kunit resource cleanup frees the drm driver
Kunit resource cleanup puts the struct device, which starts a
      device-managed resource cleanup
device-managed cleanup calls drm_dev_put()
drm_dev_put() dereferences the (now freed) drm driver -&gt; Boom.

Related KASAN message:
[55272.551542] ==================================================================
[55272.551551] BUG: KASAN: slab-use-after-free in drm_dev_put.part.0+0xd4/0xe0 [drm]
[55272.551603] Read of size 8 at addr ffff888127502828 by task kunit_try_catch/10353

[55272.551612] CPU: 4 PID: 10353 Comm: kunit_try_catch Tainted: G     U           N 6.5.0-rc7+ #155
[55272.551620] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 0403 01/26/2021
[55272.551626] Call Trace:
[55272.551629]  &lt;TASK&gt;
[55272.551633]  dump_stack_lvl+0x57/0x90
[55272.551639]  print_report+0xcf/0x630
[55272.551645]  ? _raw_spin_lock_irqsave+0x5f/0x70
[55272.551652]  ? drm_dev_put.part.0+0xd4/0xe0 [drm]
[55272.551694]  kasan_report+0xd7/0x110
[55272.551699]  ? drm_dev_put.part.0+0xd4/0xe0 [drm]
[55272.551742]  drm_dev_put.part.0+0xd4/0xe0 [drm]
[55272.551783]  devres_release_all+0x15d/0x1f0
[55272.551790]  ? __pfx_devres_release_all+0x10/0x10
[55272.551797]  device_unbind_cleanup+0x16/0x1a0
[55272.551802]  device_release_driver_internal+0x3e5/0x540
[55272.551808]  ? kobject_put+0x5d/0x4b0
[55272.551814]  bus_remove_device+0x1f1/0x3f0
[55272.551819]  device_del+0x342/0x910
[55272.551826]  ? __pfx_device_del+0x10/0x10
[55272.551830]  ? lock_release+0x339/0x5e0
[55272.551836]  ? kunit_remove_resource+0x128/0x290 [kunit]
[55272.551845]  ? __pfx_lock_release+0x10/0x10
[55272.551851]  platform_device_del.part.0+0x1f/0x1e0
[55272.551856]  ? _raw_spin_unlock_irqrestore+0x30/0x60
[55272.551863]  kunit_remove_resource+0x195/0x290 [kunit]
[55272.551871]  ? _raw_spin_unlock_irqrestore+0x30/0x60
[55272.551877]  kunit_cleanup+0x78/0x120 [kunit]
[55272.551885]  ? __kthread_parkme+0xc1/0x1f0
[55272.551891]  ? __pfx_kunit_try_run_case_cleanup+0x10/0x10 [kunit]
[55272.551900]  ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [kunit]
[55272.551909]  kunit_generic_run_threadfn_adapter+0x4a/0x90 [kunit]
[55272.551919]  kthread+0x2e7/0x3c0
[55272.551924]  ? __pfx_kthread+0x10/0x10
[55272.551929]  ret_from_fork+0x2d/0x70
[55272.551935]  ? __pfx_kthread+0x10/0x10
[55272.551940]  ret_from_fork_asm+0x1b/0x30
[55272.551948]  &lt;/TASK&gt;

[55272.551953] Allocated by task 10351:
[55272.551956]  kasan_save_stack+0x1c/0x40
[55272.551962]  kasan_set_track+0x21/0x30
[55272.551966]  __kasan_kmalloc+0x8b/0x90
[55272.551970]  __kmalloc+0x5e/0x160
[55272.551976]  kunit_kmalloc_array+0x1c/0x50 [kunit]
[55272.551984]  drm_exec_test_init+0xfa/0x2c0 [drm_exec_test]
[55272.551991]  kunit_try_run_case+0xdd/0x250 [kunit]
[55272.551999]  kunit_generic_run_threadfn_adapter+0x4a/0x90 [kunit]
[55272.552008]  kthread+0x2e7/0x3c0
[55272.552012]  ret_from_fork+0x2d/0x70
[55272.552017]  ret_from_fork_asm+0x1b/0x30

[55272.552024] Freed by task 10353:
[55272.552027]  kasan_save_stack+0x1c/0x40
[55272.552032]  kasan_set_track+0x21/0x30
[55272.552036]  kasan_save_free_info+0x27/0x40
[55272.552041]  __kasan_slab_free+0x106/0x180
[55272.552046]  slab_free_freelist_hook+0xb3/0x160
[55272.552051]  __kmem_cache_free+0xb2/0x290
[55272.552056]  kunit_remove_resource+0x195/0x290 [kunit]
[55272.552064]  kunit_cleanup+0x78/0x120 [kunit]
[55272.552072]  kunit_generic_run_threadfn_adapter+0x4a/0x90 [kunit]
[55272.552080]  kthread+0x2e7/0x3c0
[55272.552085]  ret_from_fork+0x2d/0x70
[55272.552089]  ret_from_fork_asm+0x1b/0x30

[55272.552096] The buggy address belongs to the object at ffff888127502800
                which belongs to the cache kmalloc-512 of size 512
[55272.552105] The buggy address is located 40 bytes inside of
                freed 512-byte region [ffff888127502800, ffff888127502a00)

[55272.552115] The buggy address belongs to the physical page:
[55272.552119] page:00000000af6c70ff refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x127500
[55272.552127] head:00000000af6c70ff order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
[55272.552133] anon flags: 0x17ffffc0010200(slab|head|node=0|zone=2|lastcpupid=0x1fffff)
[55272.552141] page_type: 0xffffffff()
[55272.552145] raw: 0017ffffc0010200 ffff888100042c80 0000000000000000 dead000000000001
[55272.552152] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[55272.552157] page dumped because: kasan: bad access detected

[55272.552163] Memory state around the buggy address:
[55272.552167]  ffff888127502700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[55272.552173]  ffff888127502780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[55272.552178] &gt;ffff888127502800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[55272.552184]                                   ^
[55272.552187]  ffff888127502880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[55272.552193]  ffff888127502900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[55272.552198] ==================================================================
[55272.552203] Disabling lock debugging due to kernel taint

v2:
- Update commit message, add Fixes: tag and Cc stable.
v3:
- Further commit message updates (Maxime Ripard).

Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Maxime Ripard &lt;mripard@kernel.org&gt;
Cc: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Cc: David Airlie &lt;airlied@gmail.com&gt;
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: dri-devel@lists.freedesktop.org
Cc: stable@vger.kernel.org # v6.3+
Fixes: d98780310719 ("drm/tests: helpers: Allow to pass a custom drm_driver")
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Reviewed-by: Francois Dugast &lt;francois.dugast@intel.com&gt;
Acked-by: Maxime Ripard &lt;mripard@kernel.org&gt;
Link: https://lore.kernel.org/r/20230907135339.7971-2-thomas.hellstrom@linux.intel.com
Signed-off-by: Maxime Ripard &lt;mripard@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'drm-misc-next-fixes-2023-09-11' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes</title>
<updated>2023-09-11T14:23:42+00:00</updated>
<author>
<name>Daniel Vetter</name>
<email>daniel.vetter@ffwll.ch</email>
</author>
<published>2023-09-11T14:23:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=afaf2b38025ab327c85e218f36d1819e777d4d45'/>
<id>urn:sha1:afaf2b38025ab327c85e218f36d1819e777d4d45</id>
<content type='text'>
Short summary of fixes pull:

 * nouveau: Lockdep workaround
 * fbdev/g364fb: Build fix

Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
From: Thomas Zimmermann &lt;tzimmermann@suse.de&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20230911141915.GA983@linux-uq9g
</content>
</entry>
<entry>
<title>drm/drm_exec: Work around a WW mutex lockdep oddity</title>
<updated>2023-09-07T08:30:12+00:00</updated>
<author>
<name>Thomas Hellström</name>
<email>thomas.hellstrom@linux.intel.com</email>
</author>
<published>2023-09-06T09:50:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d20b484c674d2eae816978a98fa38b4054aeca3b'/>
<id>urn:sha1:d20b484c674d2eae816978a98fa38b4054aeca3b</id>
<content type='text'>
If *any* object of a certain WW mutex class is locked, lockdep will
consider *all* mutexes of that class as locked. Also the lock allocation
tracking code will apparently register only the address of the first
mutex of a given class locked in a sequence.
This has the odd consequence that if that first mutex is unlocked while
other mutexes of the same class remain locked and then its memory then
freed, the lock alloc tracking code will incorrectly assume that memory
is freed with a held lock in there.

For now, work around that for drm_exec by releasing the first grabbed
object lock last.

v2:
- Fix a typo (Danilo Krummrich)
- Reword the commit message a bit.
- Add a Fixes: tag

Related lock alloc tracking warning:
[  322.660067] =========================
[  322.660070] WARNING: held lock freed!
[  322.660074] 6.5.0-rc7+ #155 Tainted: G     U           N
[  322.660078] -------------------------
[  322.660081] kunit_try_catch/4981 is freeing memory ffff888112adc000-ffff888112adc3ff, with a lock still held there!
[  322.660089] ffff888112adc1a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x11a/0x600 [drm_exec]
[  322.660104] 2 locks held by kunit_try_catch/4981:
[  322.660108]  #0: ffffc9000343fe18 (reservation_ww_class_acquire){+.+.}-{0:0}, at: test_early_put+0x22f/0x490 [drm_exec_test]
[  322.660123]  #1: ffff888112adc1a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x11a/0x600 [drm_exec]
[  322.660135]
               stack backtrace:
[  322.660139] CPU: 7 PID: 4981 Comm: kunit_try_catch Tainted: G     U           N 6.5.0-rc7+ #155
[  322.660146] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 0403 01/26/2021
[  322.660152] Call Trace:
[  322.660155]  &lt;TASK&gt;
[  322.660158]  dump_stack_lvl+0x57/0x90
[  322.660164]  debug_check_no_locks_freed+0x20b/0x2b0
[  322.660172]  slab_free_freelist_hook+0xa1/0x160
[  322.660179]  ? drm_exec_unlock_all+0x168/0x2a0 [drm_exec]
[  322.660186]  __kmem_cache_free+0xb2/0x290
[  322.660192]  drm_exec_unlock_all+0x168/0x2a0 [drm_exec]
[  322.660200]  drm_exec_fini+0xf/0x1c0 [drm_exec]
[  322.660206]  test_early_put+0x289/0x490 [drm_exec_test]
[  322.660215]  ? __pfx_test_early_put+0x10/0x10 [drm_exec_test]
[  322.660222]  ? __kasan_check_byte+0xf/0x40
[  322.660227]  ? __ksize+0x63/0x140
[  322.660233]  ? drmm_add_final_kfree+0x3e/0xa0 [drm]
[  322.660289]  ? _raw_spin_unlock_irqrestore+0x30/0x60
[  322.660294]  ? lockdep_hardirqs_on+0x7d/0x100
[  322.660301]  ? __pfx_kunit_try_run_case+0x10/0x10 [kunit]
[  322.660310]  ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [kunit]
[  322.660319]  kunit_generic_run_threadfn_adapter+0x4a/0x90 [kunit]
[  322.660328]  kthread+0x2e7/0x3c0
[  322.660334]  ? __pfx_kthread+0x10/0x10
[  322.660339]  ret_from_fork+0x2d/0x70
[  322.660345]  ? __pfx_kthread+0x10/0x10
[  322.660349]  ret_from_fork_asm+0x1b/0x30
[  322.660358]  &lt;/TASK&gt;
[  322.660818]     ok 8 test_early_put

Cc: Christian König &lt;christian.koenig@amd.com&gt;
Cc: Boris Brezillon &lt;boris.brezillon@collabora.com&gt;
Cc: Danilo Krummrich &lt;dakr@redhat.com&gt;
Cc: dri-devel@lists.freedesktop.org
Fixes: 09593216bff1 ("drm: execution context for GEM buffers v7")
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Reviewed-by: Boris Brezillon &lt;boris.brezillon@collabora.com&gt;
Reviewed-by: Danilo Krummrich &lt;dakr@redhat.com&gt;
Reviewed-by: Christian König &lt;christian.koenig@amd.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20230906095039.3320-4-thomas.hellstrom@linux.intel.com
</content>
</entry>
</feed>
