6.7-stable review patch. If anyone has any objections, please let me know.
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From: Luben Tuikov ltuikov89@gmail.com
[ Upstream commit 2bbe6ab2be53858507f11f99f856846d04765ae3 ]
If we're given a malformed entity in drm_sched_entity_init()--shouldn't happen, but we verify--with out-of-bounds priority value, we set it to an allowed value. Fix the expression which sets this limit.
Signed-off-by: Luben Tuikov ltuikov89@gmail.com Fixes: 56e449603f0ac5 ("drm/sched: Convert the GPU scheduler to variable number of run-queues") Link: https://patchwork.freedesktop.org/patch/msgid/20231123122422.167832-2-ltuiko... Reviewed-by: Christian König christian.koenig@amd.com Link: https://lore.kernel.org/r/dbb91dbe-ef77-4d79-aaf9-2adb171c1d7a@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/scheduler/sched_entity.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 409e4256f6e7..0a7a7e4ad8d1 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -81,12 +81,15 @@ int drm_sched_entity_init(struct drm_sched_entity *entity, */ pr_warn("%s: called with uninitialized scheduler\n", __func__); } else if (num_sched_list) { - /* The "priority" of an entity cannot exceed the number - * of run-queues of a scheduler. + /* The "priority" of an entity cannot exceed the number of run-queues of a + * scheduler. Protect against num_rqs being 0, by converting to signed. */ - if (entity->priority >= sched_list[0]->num_rqs) - entity->priority = max_t(u32, sched_list[0]->num_rqs, - DRM_SCHED_PRIORITY_MIN); + if (entity->priority >= sched_list[0]->num_rqs) { + drm_err(sched_list[0], "entity with out-of-bounds priority:%u num_rqs:%u\n", + entity->priority, sched_list[0]->num_rqs); + entity->priority = max_t(s32, (s32) sched_list[0]->num_rqs - 1, + (s32) DRM_SCHED_PRIORITY_MIN); + } entity->rq = sched_list[0]->sched_rq[entity->priority]; }