This is a note to let you know that I've just added the patch titled
drm/sched: Add locking to drm_sched_entity_modify_sched
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-sched-add-locking-to-drm_sched_entity_modify_sched.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From 4286cc2c953983d44d248c9de1c81d3a9643345c Mon Sep 17 00:00:00 2001
From: Tvrtko Ursulin <[email protected]>
Date: Fri, 13 Sep 2024 17:05:52 +0100
Subject: drm/sched: Add locking to drm_sched_entity_modify_sched
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From: Tvrtko Ursulin <[email protected]>
commit 4286cc2c953983d44d248c9de1c81d3a9643345c upstream.
Without the locking amdgpu currently can race between
amdgpu_ctx_set_entity_priority() (via drm_sched_entity_modify_sched()) and
drm_sched_job_arm(), leading to the latter accesing potentially
inconsitent entity->sched_list and entity->num_sched_list pair.
v2:
* Improve commit message. (Philipp)
Signed-off-by: Tvrtko Ursulin <[email protected]>
Fixes: b37aced31eb0 ("drm/scheduler: implement a function to modify sched list")
Cc: Christian König <[email protected]>
Cc: Alex Deucher <[email protected]>
Cc: Luben Tuikov <[email protected]>
Cc: Matthew Brost <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: [email protected]
Cc: Philipp Stanner <[email protected]>
Cc: <[email protected]> # v5.7+
Reviewed-by: Christian König <[email protected]>
Link:
https://patchwork.freedesktop.org/patch/msgid/[email protected]
Signed-off-by: Christian König <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/gpu/drm/scheduler/sched_entity.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -99,8 +99,10 @@ void drm_sched_entity_modify_sched(struc
{
WARN_ON(!num_sched_list || !sched_list);
+ spin_lock(&entity->rq_lock);
entity->sched_list = sched_list;
entity->num_sched_list = num_sched_list;
+ spin_unlock(&entity->rq_lock);
}
EXPORT_SYMBOL(drm_sched_entity_modify_sched);
Patches currently in stable-queue which might be from [email protected]
are
queue-5.15/drm-sched-add-locking-to-drm_sched_entity_modify_sched.patch
