kernel/linux.git/drivers/gpu/drm/scheduler, branch v6.19.11

drm/sched: Fix kernel-doc warning for drm_sched_job_done()

2026-03-12T11:09:54+00:00

[ Upstream commit 61ded1083b264ff67ca8c2de822c66b6febaf9a8 ] There is a kernel-doc warning for the scheduler: Warning: drivers/gpu/drm/scheduler/sched_main.c:367 function parameter 'result' not described in 'drm_sched_job_done' Fix the warning by describing the undocumented error code. Fixes: 539f9ee4b52a ("drm/scheduler: properly forward fence errors") Signed-off-by: Yujie Liu [phasta: Flesh out commit message] Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20260227082452.1802922-1-yujie.liu@intel.com Signed-off-by: Sasha Levin

Merge tag 'v6.18-rc6' into drm-next

2025-11-20T22:55:08+00:00

Linux 6.18-rc6 Backmerge in order to merge msm next Signed-off-by: Dave Airlie

drm/sched: Replace use of system_wq with system_percpu_wq

2025-11-07T08:09:03+00:00

In the general workqueue implementation, if a user enqueues a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistency cannot be addressed without refactoring the API. For more details see the Link tag below. This continues the effort to refactor worqueue APIs, which has begun with the change introducing new workqueues and a new alloc_workqueue flag: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") Use the successor of system_wq, system_percpu_wq, for the scheduler's default timeout_wq. system_wq will be removed in a few release cycles. Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/ Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251106150121.256367-1-marco.crivellari@suse.com

drm/sched: Fix deadlock in drm_sched_entity_kill_jobs_cb

2025-11-05T11:29:52+00:00

The Mesa issue referenced below pointed out a possible deadlock: [ 1231.611031] Possible interrupt unsafe locking scenario: [ 1231.611033] CPU0 CPU1 [ 1231.611034] ---- ---- [ 1231.611035] lock(&xa->xa_lock#17); [ 1231.611038] local_irq_disable(); [ 1231.611039] lock(&fence->lock); [ 1231.611041] lock(&xa->xa_lock#17); [ 1231.611044] [ 1231.611045] lock(&fence->lock); [ 1231.611047] *** DEADLOCK *** In this example, CPU0 would be any function accessing job->dependencies through the xa_* functions that don't disable interrupts (eg: drm_sched_job_add_dependency(), drm_sched_entity_kill_jobs_cb()). CPU1 is executing drm_sched_entity_kill_jobs_cb() as a fence signalling callback so in an interrupt context. It will deadlock when trying to grab the xa_lock which is already held by CPU0. Replacing all xa_* usage by their xa_*_irq counterparts would fix this issue, but Christian pointed out another issue: dma_fence_signal takes fence.lock and so does dma_fence_add_callback. dma_fence_signal() // locks f1.lock -> drm_sched_entity_kill_jobs_cb() -> foreach dependencies -> dma_fence_add_callback() // locks f2.lock This will deadlock if f1 and f2 share the same spinlock. To fix both issues, the code iterating on dependencies and re-arming them is moved out to drm_sched_entity_kill_jobs_work(). Cc: stable@vger.kernel.org # v6.2+ Fixes: 2fdb8a8f07c2 ("drm/scheduler: rework entity flush, kill and fini") Link: https://gitlab.freedesktop.org/mesa/mesa/-/issues/13908 Reported-by: Mikhail Gavrilov Suggested-by: Christian König Reviewed-by: Christian König Signed-off-by: Pierre-Eric Pelloux-Prayer [phasta: commit message nits] Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251104095358.15092-1-pierre-eric.pelloux-prayer@amd.com

drm/sched: Add warning for removing hack in drm_sched_fini()

2025-10-31T14:39:08+00:00

The assembled developers agreed at the X.Org Developers Conference 2025 that the hack added for amdgpu in drm_sched_fini() shall be removed. It shouldn't be needed by amdgpu anymore. As it's unclear whether all drivers really follow the life time rule of entities having to be torn down before their scheduler, it is reasonable to warn for a while before removing the hack. Add a warning in drm_sched_fini() that fires if an entity is still active. Acked-by: Pierre-Eric Pelloux-Prayer Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251023123429.139848-2-phasta@kernel.org

drm/sched: Fix comment in drm_sched_run_job_work()

2025-10-31T10:09:00+00:00

drm_sched_run_job_work() contains a comment which explains that an entity being NULL means that there is no more work to do. It can, however, also mean that there is work, but the scheduler doesn't have enough credits to process the jobs right now. Provide this detail in the comment. Reviewed-by: Matthew Brost Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251028134602.94125-3-phasta@kernel.org

drm/sched: avoid killing parent entity on child SIGKILL

2025-10-28T13:11:42+00:00

The DRM scheduler tracks who last uses an entity and when that process is killed blocks all further submissions to that entity. The problem is that we didn't track who initially created an entity, so when a process accidently leaked its file descriptor to a child and that child got killed, we killed the parent's entities. Avoid that and instead initialize the entities last user on entity creation. This also allows to drop the extra NULL check. Signed-off-by: David Rosca Signed-off-by: Christian König Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4568 Reviewed-by: Alex Deucher CC: stable@vger.kernel.org Acked-by: Philipp Stanner Link: https://lore.kernel.org/r/20251015140128.1470-1-christian.koenig@amd.com Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251015140128.1470-1-christian.koenig@amd.com

drm/sched: Fix race in drm_sched_entity_select_rq()

2025-10-27T12:48:46+00:00

In a past bug fix it was forgotten that entity access must be protected by the entity lock. That's a data race and potentially UB. Move the spin_unlock() to the appropriate position. Cc: stable@vger.kernel.org # v5.13+ Fixes: ac4eb83ab255 ("drm/sched: select new rq even if there is only one v3") Reviewed-by: Tvrtko Ursulin Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251022063402.87318-2-phasta@kernel.org

Merge tag 'drm-misc-next-2025-10-02' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-next

2025-10-21T08:16:34+00:00

drm-misc-next for v6.19: UAPI Changes: Cross-subsystem Changes: - fbcon cleanups. - Make drivers depend on FB_TILEBLITTING instead of selecting it, and hide FB_MODE_HELPERS. Core Changes: - More preparations for rust. - Throttle dirty worker with vblank - Use drm_for_each_bridge_in_chain_scoped in drm's bridge code and assorted fixes. - Ensure drm_client_modeset tests are enabled in UML. - Rename ttm_bo_put to ttm_bo_fini, as a further step in removing the TTM bo refcount. - Add POST_LT_ADJ_REQ training sequence. - Show list of removed but still allocated bridges. - Add a simulated vblank interrupt for hardware without it, and add some helpers to use them in vkms and hypervdrm. Driver Changes: - Assorted small fixes, cleanups and updates to host1x, tegra, panthor, amdxdna, gud, vc4, ssd130x, ivpu, panfrost, panthor, sysfb, bridge/sn65dsi86, solomon, ast, tidss. - Convert drivers from using .round_rate() to .determine_rate() - Add support for KD116N3730A07/A12, chromebook mt8189, JT101TM023, LQ079L1SX01, raspberrypi 5" panels. - Improve reclocking on tegra186+ with nouveau. - Improve runtime pm in amdxdna. - Add support for HTX_PAI in imx. - Use a helper to calculate dumb buffer sizes in most drivers. Signed-off-by: Simona Vetter From: Maarten Lankhorst Link: https://lore.kernel.org/r/b412fb91-8545-466a-8102-d89c0f2758a7@linux.intel.com

drm/sched: Fix potential double free in drm_sched_job_add_resv_dependencies

2025-10-16T12:26:05+00:00

When adding dependencies with drm_sched_job_add_dependency(), that function consumes the fence reference both on success and failure, so in the latter case the dma_fence_put() on the error path (xarray failed to expand) is a double free. Interestingly this bug appears to have been present ever since commit ebd5f74255b9 ("drm/sched: Add dependency tracking"), since the code back then looked like this: drm_sched_job_add_implicit_dependencies(): ... for (i = 0; i < fence_count; i++) { ret = drm_sched_job_add_dependency(job, fences[i]); if (ret) break; } for (; i < fence_count; i++) dma_fence_put(fences[i]); Which means for the failing 'i' the dma_fence_put was already a double free. Possibly there were no users at that time, or the test cases were insufficient to hit it. The bug was then only noticed and fixed after commit 9c2ba265352a ("drm/scheduler: use new iterator in drm_sched_job_add_implicit_dependencies v2") landed, with its fixup of commit 4eaf02d6076c ("drm/scheduler: fix drm_sched_job_add_implicit_dependencies"). At that point it was a slightly different flavour of a double free, which commit 963d0b356935 ("drm/scheduler: fix drm_sched_job_add_implicit_dependencies harder") noticed and attempted to fix. But it only moved the double free from happening inside the drm_sched_job_add_dependency(), when releasing the reference not yet obtained, to the caller, when releasing the reference already released by the former in the failure case. As such it is not easy to identify the right target for the fixes tag so lets keep it simple and just continue the chain. While fixing we also improve the comment and explain the reason for taking the reference and not dropping it. Signed-off-by: Tvrtko Ursulin Fixes: 963d0b356935 ("drm/scheduler: fix drm_sched_job_add_implicit_dependencies harder") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/dri-devel/aNFbXq8OeYl3QSdm@stanley.mountain/ Cc: Christian König Cc: Rob Clark Cc: Daniel Vetter Cc: Matthew Brost Cc: Danilo Krummrich Cc: Philipp Stanner Cc: Christian König Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v5.16+ Signed-off-by: Philipp Stanner Link: https://lore.kernel.org/r/20251015084015.6273-1-tvrtko.ursulin@igalia.com