<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/gpu/drm, branch v6.18.4</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>drm/imagination: Disallow exporting of PM/FW protected objects</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Alessio Belle</name>
<email>alessio.belle@imgtec.com</email>
</author>
<published>2025-12-08T09:11:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e8469ef3d480130a47008f523c9808ffc05fe31e'/>
<id>e8469ef3d480130a47008f523c9808ffc05fe31e</id>
<content type='text'>
commit 6b991ad8dc3abfe5720fc2e9ee96be63ae43e362 upstream.

These objects are meant to be used by the GPU firmware or by the PM unit
within the GPU, in which case they may contain physical addresses.

This adds a layer of protection against exposing potentially exploitable
information outside of the driver.

Fixes: ff5f643de0bf ("drm/imagination: Add GEM and VM related code")
Signed-off-by: Alessio Belle &lt;alessio.belle@imgtec.com&gt;
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20251208-no-export-pm-fw-obj-v1-1-83ab12c61693@imgtec.com
Signed-off-by: Matt Coster &lt;matt.coster@imgtec.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 6b991ad8dc3abfe5720fc2e9ee96be63ae43e362 upstream.

These objects are meant to be used by the GPU firmware or by the PM unit
within the GPU, in which case they may contain physical addresses.

This adds a layer of protection against exposing potentially exploitable
information outside of the driver.

Fixes: ff5f643de0bf ("drm/imagination: Add GEM and VM related code")
Signed-off-by: Alessio Belle &lt;alessio.belle@imgtec.com&gt;
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20251208-no-export-pm-fw-obj-v1-1-83ab12c61693@imgtec.com
Signed-off-by: Matt Coster &lt;matt.coster@imgtec.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/nouveau/dispnv50: Don't call drm_atomic_get_crtc_state() in prepare_fb</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Lyude Paul</name>
<email>lyude@redhat.com</email>
</author>
<published>2025-12-11T19:02:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5487edb7b8ede8a6f2d034a6da6ee4a56f5b1626'/>
<id>5487edb7b8ede8a6f2d034a6da6ee4a56f5b1626</id>
<content type='text'>
commit 560271e10b2c86e95ea35afa9e79822e4847f07a upstream.

Since we recently started warning about uses of this function after the
atomic check phase completes, we've started getting warnings about this in
nouveau. It appears a misplaced drm_atomic_get_crtc_state() call has been
hiding in our .prepare_fb callback for a while.

So, fix this by adding a new nv50_head_atom_get_new() function and use that
in our .prepare_fb callback instead.

Signed-off-by: Lyude Paul &lt;lyude@redhat.com&gt;
Reviewed-by: Dave Airlie &lt;airlied@redhat.com&gt;
Fixes: 1590700d94ac ("drm/nouveau/kms/nv50-: split each resource type into their own source files")
Cc: &lt;stable@vger.kernel.org&gt; # v4.18+
Link: https://patch.msgid.link/20251211190256.396742-1-lyude@redhat.com
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 560271e10b2c86e95ea35afa9e79822e4847f07a upstream.

Since we recently started warning about uses of this function after the
atomic check phase completes, we've started getting warnings about this in
nouveau. It appears a misplaced drm_atomic_get_crtc_state() call has been
hiding in our .prepare_fb callback for a while.

So, fix this by adding a new nv50_head_atom_get_new() function and use that
in our .prepare_fb callback instead.

Signed-off-by: Lyude Paul &lt;lyude@redhat.com&gt;
Reviewed-by: Dave Airlie &lt;airlied@redhat.com&gt;
Fixes: 1590700d94ac ("drm/nouveau/kms/nv50-: split each resource type into their own source files")
Cc: &lt;stable@vger.kernel.org&gt; # v4.18+
Link: https://patch.msgid.link/20251211190256.396742-1-lyude@redhat.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/pagemap, drm/xe: Ensure that the devmem allocation is idle before use</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Thomas Hellström</name>
<email>thomas.hellstrom@linux.intel.com</email>
</author>
<published>2025-12-19T11:32:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c79ee71f45987a753789c3fede6a34499080584e'/>
<id>c79ee71f45987a753789c3fede6a34499080584e</id>
<content type='text'>
commit 754c23238438600e9236719f7e67aff2c4d02093 upstream.

In situations where no system memory is migrated to devmem, and in
upcoming patches where another GPU is performing the migration to
the newly allocated devmem buffer, there is nothing to ensure any
ongoing clear to the devmem allocation or async eviction from the
devmem allocation is complete.

Address that by passing a struct dma_fence down to the copy
functions, and ensure it is waited for before migration is marked
complete.

v3:
- New patch.
v4:
- Update the logic used for determining when to wait for the
  pre_migrate_fence.
- Update the logic used for determining when to warn for the
  pre_migrate_fence since the scheduler fences apparently
  can signal out-of-order.
v5:
- Fix a UAF (CI)
- Remove references to source P2P migration (Himal)
- Put the pre_migrate_fence after migration.
v6:
- Pipeline the pre_migrate_fence dependency (Matt Brost)

Fixes: c5b3eb5a906c ("drm/xe: Add GPUSVM device memory copy vfunc functions")
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.15+
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Reviewed-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Acked-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt; # For merging through drm-xe.
Link: https://patch.msgid.link/20251219113320.183860-4-thomas.hellstrom@linux.intel.com
(cherry picked from commit 16b5ad31952476fb925c401897fc171cd37f536b)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.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 754c23238438600e9236719f7e67aff2c4d02093 upstream.

In situations where no system memory is migrated to devmem, and in
upcoming patches where another GPU is performing the migration to
the newly allocated devmem buffer, there is nothing to ensure any
ongoing clear to the devmem allocation or async eviction from the
devmem allocation is complete.

Address that by passing a struct dma_fence down to the copy
functions, and ensure it is waited for before migration is marked
complete.

v3:
- New patch.
v4:
- Update the logic used for determining when to wait for the
  pre_migrate_fence.
- Update the logic used for determining when to warn for the
  pre_migrate_fence since the scheduler fences apparently
  can signal out-of-order.
v5:
- Fix a UAF (CI)
- Remove references to source P2P migration (Himal)
- Put the pre_migrate_fence after migration.
v6:
- Pipeline the pre_migrate_fence dependency (Matt Brost)

Fixes: c5b3eb5a906c ("drm/xe: Add GPUSVM device memory copy vfunc functions")
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.15+
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Reviewed-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Acked-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt; # For merging through drm-xe.
Link: https://patch.msgid.link/20251219113320.183860-4-thomas.hellstrom@linux.intel.com
(cherry picked from commit 16b5ad31952476fb925c401897fc171cd37f536b)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/xe/svm: Fix a debug printout</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Thomas Hellström</name>
<email>thomas.hellstrom@linux.intel.com</email>
</author>
<published>2025-12-19T11:32:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=548f139d3c17209a50522e41258b206c31f4ff7e'/>
<id>548f139d3c17209a50522e41258b206c31f4ff7e</id>
<content type='text'>
commit d2d7f5636f0d752a1e0e7eadbbc1839c29177bba upstream.

Avoid spamming the log with drm_info(). Use drm_dbg() instead.

Fixes: cc795e041034 ("drm/xe/svm: Make xe_svm_range_needs_migrate_to_vram() public")
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: Himal Prasad Ghimiray &lt;himal.prasad.ghimiray@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.17+
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Reviewed-by: Himal Prasad Ghimiray &lt;himal.prasad.ghimiray@intel.com&gt;
Link: https://patch.msgid.link/20251219113320.183860-2-thomas.hellstrom@linux.intel.com
(cherry picked from commit 72aee5f70ba47b939345a0d3414b51b0639c5b88)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.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 d2d7f5636f0d752a1e0e7eadbbc1839c29177bba upstream.

Avoid spamming the log with drm_info(). Use drm_dbg() instead.

Fixes: cc795e041034 ("drm/xe/svm: Make xe_svm_range_needs_migrate_to_vram() public")
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: Himal Prasad Ghimiray &lt;himal.prasad.ghimiray@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.17+
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Reviewed-by: Himal Prasad Ghimiray &lt;himal.prasad.ghimiray@intel.com&gt;
Link: https://patch.msgid.link/20251219113320.183860-2-thomas.hellstrom@linux.intel.com
(cherry picked from commit 72aee5f70ba47b939345a0d3414b51b0639c5b88)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/i915/gem: Zero-initialize the eb.vma array in i915_gem_do_execbuffer</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Krzysztof Niemiec</name>
<email>krzysztof.niemiec@intel.com</email>
</author>
<published>2025-12-16T18:09:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=63f23aa2fbb823c8b15a29269fde220d227ce5b3'/>
<id>63f23aa2fbb823c8b15a29269fde220d227ce5b3</id>
<content type='text'>
commit 4fe2bd195435e71c117983d87f278112c5ab364c upstream.

Initialize the eb.vma array with values of 0 when the eb structure is
first set up. In particular, this sets the eb-&gt;vma[i].vma pointers to
NULL, simplifying cleanup and getting rid of the bug described below.

During the execution of eb_lookup_vmas(), the eb-&gt;vma array is
successively filled up with struct eb_vma objects. This process includes
calling eb_add_vma(), which might fail; however, even in the event of
failure, eb-&gt;vma[i].vma is set for the currently processed buffer.

If eb_add_vma() fails, eb_lookup_vmas() returns with an error, which
prompts a call to eb_release_vmas() to clean up the mess. Since
eb_lookup_vmas() might fail during processing any (possibly not first)
buffer, eb_release_vmas() checks whether a buffer's vma is NULL to know
at what point did the lookup function fail.

In eb_lookup_vmas(), eb-&gt;vma[i].vma is set to NULL if either the helper
function eb_lookup_vma() or eb_validate_vma() fails. eb-&gt;vma[i+1].vma is
set to NULL in case i915_gem_object_userptr_submit_init() fails; the
current one needs to be cleaned up by eb_release_vmas() at this point,
so the next one is set. If eb_add_vma() fails, neither the current nor
the next vma is set to NULL, which is a source of a NULL deref bug
described in the issue linked in the Closes tag.

When entering eb_lookup_vmas(), the vma pointers are set to the slab
poison value, instead of NULL. This doesn't matter for the actual
lookup, since it gets overwritten anyway, however the eb_release_vmas()
function only recognizes NULL as the stopping value, hence the pointers
are being set to NULL as they go in case of intermediate failure. This
patch changes the approach to filling them all with NULL at the start
instead, rather than handling that manually during failure.

Reported-by: Gangmin Kim &lt;km.kim1503@gmail.com&gt;
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15062
Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf")
Cc: stable@vger.kernel.org # 5.16.x
Signed-off-by: Krzysztof Niemiec &lt;krzysztof.niemiec@intel.com&gt;
Reviewed-by: Janusz Krzysztofik &lt;janusz.krzysztofik@linux.intel.com&gt;
Reviewed-by: Krzysztof Karas &lt;krzysztof.karas@intel.com&gt;
Reviewed-by: Andi Shyti &lt;andi.shyti@linux.intel.com&gt;
Signed-off-by: Andi Shyti &lt;andi.shyti@kernel.org&gt;
Link: https://lore.kernel.org/r/20251216180900.54294-2-krzysztof.niemiec@intel.com
(cherry picked from commit 08889b706d4f0b8d2352b7ca29c2d8df4d0787cd)
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 4fe2bd195435e71c117983d87f278112c5ab364c upstream.

Initialize the eb.vma array with values of 0 when the eb structure is
first set up. In particular, this sets the eb-&gt;vma[i].vma pointers to
NULL, simplifying cleanup and getting rid of the bug described below.

During the execution of eb_lookup_vmas(), the eb-&gt;vma array is
successively filled up with struct eb_vma objects. This process includes
calling eb_add_vma(), which might fail; however, even in the event of
failure, eb-&gt;vma[i].vma is set for the currently processed buffer.

If eb_add_vma() fails, eb_lookup_vmas() returns with an error, which
prompts a call to eb_release_vmas() to clean up the mess. Since
eb_lookup_vmas() might fail during processing any (possibly not first)
buffer, eb_release_vmas() checks whether a buffer's vma is NULL to know
at what point did the lookup function fail.

In eb_lookup_vmas(), eb-&gt;vma[i].vma is set to NULL if either the helper
function eb_lookup_vma() or eb_validate_vma() fails. eb-&gt;vma[i+1].vma is
set to NULL in case i915_gem_object_userptr_submit_init() fails; the
current one needs to be cleaned up by eb_release_vmas() at this point,
so the next one is set. If eb_add_vma() fails, neither the current nor
the next vma is set to NULL, which is a source of a NULL deref bug
described in the issue linked in the Closes tag.

When entering eb_lookup_vmas(), the vma pointers are set to the slab
poison value, instead of NULL. This doesn't matter for the actual
lookup, since it gets overwritten anyway, however the eb_release_vmas()
function only recognizes NULL as the stopping value, hence the pointers
are being set to NULL as they go in case of intermediate failure. This
patch changes the approach to filling them all with NULL at the start
instead, rather than handling that manually during failure.

Reported-by: Gangmin Kim &lt;km.kim1503@gmail.com&gt;
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15062
Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf")
Cc: stable@vger.kernel.org # 5.16.x
Signed-off-by: Krzysztof Niemiec &lt;krzysztof.niemiec@intel.com&gt;
Reviewed-by: Janusz Krzysztofik &lt;janusz.krzysztofik@linux.intel.com&gt;
Reviewed-by: Krzysztof Karas &lt;krzysztof.karas@intel.com&gt;
Reviewed-by: Andi Shyti &lt;andi.shyti@linux.intel.com&gt;
Signed-off-by: Andi Shyti &lt;andi.shyti@kernel.org&gt;
Link: https://lore.kernel.org/r/20251216180900.54294-2-krzysztof.niemiec@intel.com
(cherry picked from commit 08889b706d4f0b8d2352b7ca29c2d8df4d0787cd)
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/msm: add PERFCTR_CNTL to ifpc_reglist</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Anna Maniscalco</name>
<email>anna.maniscalco2000@gmail.com</email>
</author>
<published>2025-11-27T18:22:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3165fcd7a1cbdf1d7bf2fed74ef13cbd2367d782'/>
<id>3165fcd7a1cbdf1d7bf2fed74ef13cbd2367d782</id>
<content type='text'>
commit 6c6915bfea212d32844b2b7f22bc1aa3669eabc4 upstream.

Previously this register would become 0 after IFPC took place which
broke all usages of counters.

Fixes: a6a0157cc68e ("drm/msm/a6xx: Enable IFPC on Adreno X1-85")
Cc: stable@vger.kernel.org
Signed-off-by: Anna Maniscalco &lt;anna.maniscalco2000@gmail.com&gt;
Reviewed-by: Akhil P Oommen &lt;akhilpo@oss.qualcomm.com&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@oss.qualcomm.com&gt;
Patchwork: https://patchwork.freedesktop.org/patch/690960/
Message-ID: &lt;20251127-ifpc_counters-v3-1-fac0a126bc88@gmail.com&gt;
Signed-off-by: Rob Clark &lt;robin.clark@oss.qualcomm.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 6c6915bfea212d32844b2b7f22bc1aa3669eabc4 upstream.

Previously this register would become 0 after IFPC took place which
broke all usages of counters.

Fixes: a6a0157cc68e ("drm/msm/a6xx: Enable IFPC on Adreno X1-85")
Cc: stable@vger.kernel.org
Signed-off-by: Anna Maniscalco &lt;anna.maniscalco2000@gmail.com&gt;
Reviewed-by: Akhil P Oommen &lt;akhilpo@oss.qualcomm.com&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@oss.qualcomm.com&gt;
Patchwork: https://patchwork.freedesktop.org/patch/690960/
Message-ID: &lt;20251127-ifpc_counters-v3-1-fac0a126bc88@gmail.com&gt;
Signed-off-by: Rob Clark &lt;robin.clark@oss.qualcomm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/msm/dpu: Add missing NULL pointer check for pingpong interface</title>
<updated>2026-01-08T09:17:20+00:00</updated>
<author>
<name>Nikolay Kuratov</name>
<email>kniv@yandex-team.ru</email>
</author>
<published>2025-12-11T09:36:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=35ea3282136a630a3fd92b76f5a3a02651145ef1'/>
<id>35ea3282136a630a3fd92b76f5a3a02651145ef1</id>
<content type='text'>
commit 88733a0b64872357e5ecd82b7488121503cb9cc6 upstream.

It is checked almost always in dpu_encoder_phys_wb_setup_ctl(), but in a
single place the check is missing.
Also use convenient locals instead of phys_enc-&gt;* where available.

Cc: stable@vger.kernel.org
Fixes: d7d0e73f7de33 ("drm/msm/dpu: introduce the dpu_encoder_phys_* for writeback")
Signed-off-by: Nikolay Kuratov &lt;kniv@yandex-team.ru&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@oss.qualcomm.com&gt;
Patchwork: https://patchwork.freedesktop.org/patch/693860/
Link: https://lore.kernel.org/r/20251211093630.171014-1-kniv@yandex-team.ru
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@oss.qualcomm.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 88733a0b64872357e5ecd82b7488121503cb9cc6 upstream.

It is checked almost always in dpu_encoder_phys_wb_setup_ctl(), but in a
single place the check is missing.
Also use convenient locals instead of phys_enc-&gt;* where available.

Cc: stable@vger.kernel.org
Fixes: d7d0e73f7de33 ("drm/msm/dpu: introduce the dpu_encoder_phys_* for writeback")
Signed-off-by: Nikolay Kuratov &lt;kniv@yandex-team.ru&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@oss.qualcomm.com&gt;
Patchwork: https://patchwork.freedesktop.org/patch/693860/
Link: https://lore.kernel.org/r/20251211093630.171014-1-kniv@yandex-team.ru
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@oss.qualcomm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/xe: Drop preempt-fences when destroying imported dma-bufs.</title>
<updated>2026-01-08T09:17:19+00:00</updated>
<author>
<name>Thomas Hellström</name>
<email>thomas.hellstrom@linux.intel.com</email>
</author>
<published>2025-12-17T09:34:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8d9df6d3fa49c18547896d16a5414a09c0c386b0'/>
<id>8d9df6d3fa49c18547896d16a5414a09c0c386b0</id>
<content type='text'>
commit fe3ccd24138fd391ae8e32289d492c85f67770fc upstream.

When imported dma-bufs are destroyed, TTM is not fully
individualizing the dma-resv, but it *is* copying the fences that
need to be waited for before declaring idle. So in the case where
the bo-&gt;resv != bo-&gt;_resv we can still drop the preempt-fences, but
make sure we do that on bo-&gt;_resv which contains the fence-pointer
copy.

In the case where the copying fails, bo-&gt;_resv will typically not
contain any fences pointers at all, so there will be nothing to
drop. In that case, TTM would have ensured all fences that would
have been copied are signaled, including any remaining preempt
fences.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Fixes: fa0af721bd1f ("drm/ttm: test private resv obj on release/destroy")
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.16+
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Tested-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Reviewed-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Link: https://patch.msgid.link/20251217093441.5073-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit 425fe550fb513b567bd6d01f397d274092a9c274)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.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 fe3ccd24138fd391ae8e32289d492c85f67770fc upstream.

When imported dma-bufs are destroyed, TTM is not fully
individualizing the dma-resv, but it *is* copying the fences that
need to be waited for before declaring idle. So in the case where
the bo-&gt;resv != bo-&gt;_resv we can still drop the preempt-fences, but
make sure we do that on bo-&gt;_resv which contains the fence-pointer
copy.

In the case where the copying fails, bo-&gt;_resv will typically not
contain any fences pointers at all, so there will be nothing to
drop. In that case, TTM would have ensured all fences that would
have been copied are signaled, including any remaining preempt
fences.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Fixes: fa0af721bd1f ("drm/ttm: test private resv obj on release/destroy")
Cc: Matthew Brost &lt;matthew.brost@intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt; # v6.16+
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Tested-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Reviewed-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Link: https://patch.msgid.link/20251217093441.5073-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit 425fe550fb513b567bd6d01f397d274092a9c274)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/xe: Use usleep_range for accurate long-running workload timeslicing</title>
<updated>2026-01-08T09:17:19+00:00</updated>
<author>
<name>Matthew Brost</name>
<email>matthew.brost@intel.com</email>
</author>
<published>2025-12-12T18:28:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e85d0e02121db79de94777dde20ee02be3415690'/>
<id>e85d0e02121db79de94777dde20ee02be3415690</id>
<content type='text'>
commit 80f9c601d9c4d26f00356c0a9c461650e7089273 upstream.

msleep is not very accurate in terms of how long it actually sleeps,
whereas usleep_range is precise. Replace the timeslice sleep for
long-running workloads with the more accurate usleep_range to avoid
jitter if the sleep period is less than 20ms.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Reviewed-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Link: https://patch.msgid.link/20251212182847.1683222-3-matthew.brost@intel.com
(cherry picked from commit ca415c4d4c17ad676a2c8981e1fcc432221dce79)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.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 80f9c601d9c4d26f00356c0a9c461650e7089273 upstream.

msleep is not very accurate in terms of how long it actually sleeps,
whereas usleep_range is precise. Replace the timeslice sleep for
long-running workloads with the more accurate usleep_range to avoid
jitter if the sleep period is less than 20ms.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Reviewed-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Link: https://patch.msgid.link/20251212182847.1683222-3-matthew.brost@intel.com
(cherry picked from commit ca415c4d4c17ad676a2c8981e1fcc432221dce79)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>drm/xe: Adjust long-running workload timeslices to reasonable values</title>
<updated>2026-01-08T09:17:19+00:00</updated>
<author>
<name>Matthew Brost</name>
<email>matthew.brost@intel.com</email>
</author>
<published>2025-12-12T18:28:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a7229c1ebeed5768c5263766d0424c480a5e0966'/>
<id>a7229c1ebeed5768c5263766d0424c480a5e0966</id>
<content type='text'>
commit 6f0f404bd289d79a260b634c5b3f4d330b13472c upstream.

A 10ms timeslice for long-running workloads is far too long and causes
significant jitter in benchmarks when the system is shared. Adjust the
value to 5ms for preempt-fencing VMs, as the resume step there is quite
costly as memory is moved around, and set it to zero for pagefault VMs,
since switching back to pagefault mode after dma-fence mode is
relatively fast.

Also change min_run_period_ms to 'unsiged int' type rather than 's64' as
only positive values make sense.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Reviewed-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Link: https://patch.msgid.link/20251212182847.1683222-2-matthew.brost@intel.com
(cherry picked from commit 33a5abd9a68394aa67f9618b20eee65ee8702ff4)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.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 6f0f404bd289d79a260b634c5b3f4d330b13472c upstream.

A 10ms timeslice for long-running workloads is far too long and causes
significant jitter in benchmarks when the system is shared. Adjust the
value to 5ms for preempt-fencing VMs, as the resume step there is quite
costly as memory is moved around, and set it to zero for pagefault VMs,
since switching back to pagefault mode after dma-fence mode is
relatively fast.

Also change min_run_period_ms to 'unsiged int' type rather than 's64' as
only positive values make sense.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost &lt;matthew.brost@intel.com&gt;
Reviewed-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Link: https://patch.msgid.link/20251212182847.1683222-2-matthew.brost@intel.com
(cherry picked from commit 33a5abd9a68394aa67f9618b20eee65ee8702ff4)
Signed-off-by: Thomas Hellström &lt;thomas.hellstrom@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
