linux-stable.git/drivers/gpu/drm/xe, branch v6.18.4 Linux kernel stable tree drm/pagemap, drm/xe: Ensure that the devmem allocation is idle before use 2026-01-08T09:17:20+00:00 Thomas Hellström thomas.hellstrom@linux.intel.com 2025-12-19T11:32:59+00:00 c79ee71f45987a753789c3fede6a34499080584e 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 <matthew.brost@intel.com> Cc: <stable@vger.kernel.org> # v6.15+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> # 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 <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org> # v6.15+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> # 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 <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe/svm: Fix a debug printout 2026-01-08T09:17:20+00:00 Thomas Hellström thomas.hellstrom@linux.intel.com 2025-12-19T11:32:57+00:00 548f139d3c17209a50522e41258b206c31f4ff7e 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 <matthew.brost@intel.com> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com> Cc: <stable@vger.kernel.org> # v6.17+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com> Link: https://patch.msgid.link/20251219113320.183860-2-thomas.hellstrom@linux.intel.com (cherry picked from commit 72aee5f70ba47b939345a0d3414b51b0639c5b88) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <matthew.brost@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Cc: <stable@vger.kernel.org> # v6.17+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patch.msgid.link/20251219113320.183860-2-thomas.hellstrom@linux.intel.com
(cherry picked from commit 72aee5f70ba47b939345a0d3414b51b0639c5b88)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe: Drop preempt-fences when destroying imported dma-bufs. 2026-01-08T09:17:19+00:00 Thomas Hellström thomas.hellstrom@linux.intel.com 2025-12-17T09:34:41+00:00 8d9df6d3fa49c18547896d16a5414a09c0c386b0 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->resv != bo->_resv we can still drop the preempt-fences, but make sure we do that on bo->_resv which contains the fence-pointer copy. In the case where the copying fails, bo->_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 <matthew.brost@intel.com> Cc: <stable@vger.kernel.org> # v6.16+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Tested-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Link: https://patch.msgid.link/20251217093441.5073-1-thomas.hellstrom@linux.intel.com (cherry picked from commit 425fe550fb513b567bd6d01f397d274092a9c274) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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->resv != bo->_resv we can still drop the preempt-fences, but
make sure we do that on bo->_resv which contains the fence-pointer
copy.

In the case where the copying fails, bo->_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 <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org> # v6.16+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Tested-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20251217093441.5073-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit 425fe550fb513b567bd6d01f397d274092a9c274)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe: Use usleep_range for accurate long-running workload timeslicing 2026-01-08T09:17:19+00:00 Matthew Brost matthew.brost@intel.com 2025-12-12T18:28:42+00:00 e85d0e02121db79de94777dde20ee02be3415690 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 <matthew.brost@intel.com> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Link: https://patch.msgid.link/20251212182847.1683222-3-matthew.brost@intel.com (cherry picked from commit ca415c4d4c17ad676a2c8981e1fcc432221dce79) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20251212182847.1683222-3-matthew.brost@intel.com
(cherry picked from commit ca415c4d4c17ad676a2c8981e1fcc432221dce79)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe: Adjust long-running workload timeslices to reasonable values 2026-01-08T09:17:19+00:00 Matthew Brost matthew.brost@intel.com 2025-12-12T18:28:41+00:00 a7229c1ebeed5768c5263766d0424c480a5e0966 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 <matthew.brost@intel.com> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Link: https://patch.msgid.link/20251212182847.1683222-2-matthew.brost@intel.com (cherry picked from commit 33a5abd9a68394aa67f9618b20eee65ee8702ff4) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20251212182847.1683222-2-matthew.brost@intel.com
(cherry picked from commit 33a5abd9a68394aa67f9618b20eee65ee8702ff4)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe/eustall: Disallow 0 EU stall property values 2026-01-08T09:17:19+00:00 Ashutosh Dixit ashutosh.dixit@intel.com 2025-12-12T06:18:50+00:00 3570a24eb05e9af3a8a07335c8449ebb0dee1eea commit 3767ca4166ad42fa9e34269efeaf9f15995cd92d upstream. An EU stall property value of 0 is invalid and will cause a NPD. Reported-by: Peter Senna Tschudin <peter.senna@linux.intel.com> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6453 Fixes: 1537ec85ebd7 ("drm/xe/uapi: Introduce API for EU stall sampling") Cc: stable@vger.kernel.org Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com> Reviewed-by: Harish Chegondi <harish.chegondi@intel.com> Link: https://patch.msgid.link/20251212061850.1565459-4-ashutosh.dixit@intel.com (cherry picked from commit 5bf763e908bf795da4ad538d21c1ec41f8021f76) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3767ca4166ad42fa9e34269efeaf9f15995cd92d upstream.

An EU stall property value of 0 is invalid and will cause a NPD.

Reported-by: Peter Senna Tschudin <peter.senna@linux.intel.com>
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6453
Fixes: 1537ec85ebd7 ("drm/xe/uapi: Introduce API for EU stall sampling")
Cc: stable@vger.kernel.org
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Harish Chegondi <harish.chegondi@intel.com>
Link: https://patch.msgid.link/20251212061850.1565459-4-ashutosh.dixit@intel.com
(cherry picked from commit 5bf763e908bf795da4ad538d21c1ec41f8021f76)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe/oa: Disallow 0 OA property values 2026-01-08T09:17:19+00:00 Ashutosh Dixit ashutosh.dixit@intel.com 2025-12-12T06:18:49+00:00 f19cb78876f90d424ca14949b185a6668b05aecd commit 3595114bc31d1eb5e1996164c901485c1ffac6f7 upstream. An OA property value of 0 is invalid and will cause a NPD. Reported-by: Peter Senna Tschudin <peter.senna@linux.intel.com> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6452 Fixes: cc4e6994d5a2 ("drm/xe/oa: Move functions up so they can be reused for config ioctl") Cc: stable@vger.kernel.org Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com> Reviewed-by: Harish Chegondi <harish.chegondi@intel.com> Link: https://patch.msgid.link/20251212061850.1565459-3-ashutosh.dixit@intel.com (cherry picked from commit 7a100e6ddcc47c1f6ba7a19402de86ce24790621) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3595114bc31d1eb5e1996164c901485c1ffac6f7 upstream.

An OA property value of 0 is invalid and will cause a NPD.

Reported-by: Peter Senna Tschudin <peter.senna@linux.intel.com>
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6452
Fixes: cc4e6994d5a2 ("drm/xe/oa: Move functions up so they can be reused for config ioctl")
Cc: stable@vger.kernel.org
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Harish Chegondi <harish.chegondi@intel.com>
Link: https://patch.msgid.link/20251212061850.1565459-3-ashutosh.dixit@intel.com
(cherry picked from commit 7a100e6ddcc47c1f6ba7a19402de86ce24790621)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe/bo: Don't include the CCS metadata in the dma-buf sg-table 2026-01-08T09:17:19+00:00 Thomas Hellström thomas.hellstrom@linux.intel.com 2025-12-09T20:49:20+00:00 a965d4869eefe50767966f1973cc5bb06e2eedf0 commit 449bcd5d45eb4ce26740f11f8601082fe734bed2 upstream. Some Xe bos are allocated with extra backing-store for the CCS metadata. It's never been the intention to share the CCS metadata when exporting such bos as dma-buf. Don't include it in the dma-buf sg-table. Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: <stable@vger.kernel.org> # v6.8+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com> Link: https://patch.msgid.link/20251209204920.224374-1-thomas.hellstrom@linux.intel.com (cherry picked from commit a4ebfb9d95d78a12512b435a698ee6886d712571) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 449bcd5d45eb4ce26740f11f8601082fe734bed2 upstream.

Some Xe bos are allocated with extra backing-store for the CCS
metadata. It's never been the intention to share the CCS metadata
when exporting such bos as dma-buf. Don't include it in the
dma-buf sg-table.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: <stable@vger.kernel.org> # v6.8+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Link: https://patch.msgid.link/20251209204920.224374-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit a4ebfb9d95d78a12512b435a698ee6886d712571)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe/oa: Fix potential UAF in xe_oa_add_config_ioctl() 2026-01-08T09:17:16+00:00 Sanjay Yadav sanjay.kumar.yadav@intel.com 2025-11-18T11:49:00+00:00 7cdb9a9da935c687563cc682155461fef5f9b48d commit dcb171931954c51a1a7250d558f02b8f36570783 upstream. In xe_oa_add_config_ioctl(), we accessed oa_config->id after dropping metrics_lock. Since this lock protects the lifetime of oa_config, an attacker could guess the id and call xe_oa_remove_config_ioctl() with perfect timing, freeing oa_config before we dereference it, leading to a potential use-after-free. Fix this by caching the id in a local variable while holding the lock. v2: (Matt A) - Dropped mutex_unlock(&oa->metrics_lock) ordering change from xe_oa_remove_config_ioctl() Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6614 Fixes: cdf02fe1a94a7 ("drm/xe/oa/uapi: Add/remove OA config perf ops") Cc: <stable@vger.kernel.org> # v6.11+ Suggested-by: Matthew Auld <matthew.auld@intel.com> Signed-off-by: Sanjay Yadav <sanjay.kumar.yadav@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Signed-off-by: Matthew Auld <matthew.auld@intel.com> Link: https://patch.msgid.link/20251118114859.3379952-2-sanjay.kumar.yadav@intel.com (cherry picked from commit 28aeaed130e8e587fd1b73b6d66ca41ccc5a1a31) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit dcb171931954c51a1a7250d558f02b8f36570783 upstream.

In xe_oa_add_config_ioctl(), we accessed oa_config->id after dropping
metrics_lock. Since this lock protects the lifetime of oa_config, an
attacker could guess the id and call xe_oa_remove_config_ioctl() with
perfect timing, freeing oa_config before we dereference it, leading to
a potential use-after-free.

Fix this by caching the id in a local variable while holding the lock.

v2: (Matt A)
- Dropped mutex_unlock(&oa->metrics_lock) ordering change from
  xe_oa_remove_config_ioctl()

Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6614
Fixes: cdf02fe1a94a7 ("drm/xe/oa/uapi: Add/remove OA config perf ops")
Cc: <stable@vger.kernel.org> # v6.11+
Suggested-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Sanjay Yadav <sanjay.kumar.yadav@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patch.msgid.link/20251118114859.3379952-2-sanjay.kumar.yadav@intel.com
(cherry picked from commit 28aeaed130e8e587fd1b73b6d66ca41ccc5a1a31)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drm/xe/guc: READ/WRITE_ONCE g2h_fence->done 2026-01-08T09:16:51+00:00 Jonathan Cavitt jonathan.cavitt@intel.com 2025-12-22T20:19:59+00:00 d260dff568ad6d0f0f2aef4a85058e0832d772c4 [ Upstream commit bed2a6bd20681aacfb063015c1edfab6f58a333e ] Use READ_ONCE and WRITE_ONCE when operating on g2h_fence->done to prevent the compiler from ignoring important modifications to its value. Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs") Suggested-by: Matthew Brost <matthew.brost@intel.com> Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Link: https://patch.msgid.link/20251222201957.63245-5-jonathan.cavitt@intel.com Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> (cherry picked from commit b5179dbd1c14743ae80f0aaa28eaaf35c361608f) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit bed2a6bd20681aacfb063015c1edfab6f58a333e ]

Use READ_ONCE and WRITE_ONCE when operating on g2h_fence->done
to prevent the compiler from ignoring important modifications
to its value.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20251222201957.63245-5-jonathan.cavitt@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(cherry picked from commit b5179dbd1c14743ae80f0aaa28eaaf35c361608f)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>