From df1a1ed5e1bdd9cc13148e0e5549f5ebcf76cf13 Mon Sep 17 00:00:00 2001 From: Brendan King Date: Wed, 26 Feb 2025 15:42:19 +0000 Subject: drm/imagination: avoid deadlock on fence release Do scheduler queue fence release processing on a workqueue, rather than in the release function itself. Fixes deadlock issues such as the following: [ 607.400437] ============================================ [ 607.405755] WARNING: possible recursive locking detected [ 607.415500] -------------------------------------------- [ 607.420817] weston:zfq0/24149 is trying to acquire lock: [ 607.426131] ffff000017d041a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: pvr_gem_object_vunmap+0x40/0xc0 [powervr] [ 607.436728] but task is already holding lock: [ 607.442554] ffff000017d105a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_ioctl+0x250/0x554 [ 607.451727] other info that might help us debug this: [ 607.458245] Possible unsafe locking scenario: [ 607.464155] CPU0 [ 607.466601] ---- [ 607.469044] lock(reservation_ww_class_mutex); [ 607.473584] lock(reservation_ww_class_mutex); [ 607.478114] *** DEADLOCK *** Cc: stable@vger.kernel.org Fixes: eaf01ee5ba28 ("drm/imagination: Implement job submission and scheduling") Signed-off-by: Brendan King Reviewed-by: Matt Coster Link: https://patchwork.freedesktop.org/patch/msgid/20250226-fence-release-deadlock-v2-1-6fed2fc1fe88@imgtec.com Signed-off-by: Matt Coster --- drivers/gpu/drm/imagination/pvr_queue.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'drivers/gpu/drm/imagination/pvr_queue.c') diff --git a/drivers/gpu/drm/imagination/pvr_queue.c b/drivers/gpu/drm/imagination/pvr_queue.c index c4f08432882b..f3f1c5212df7 100644 --- a/drivers/gpu/drm/imagination/pvr_queue.c +++ b/drivers/gpu/drm/imagination/pvr_queue.c @@ -109,12 +109,20 @@ pvr_queue_fence_get_driver_name(struct dma_fence *f) return PVR_DRIVER_NAME; } +static void pvr_queue_fence_release_work(struct work_struct *w) +{ + struct pvr_queue_fence *fence = container_of(w, struct pvr_queue_fence, release_work); + + pvr_context_put(fence->queue->ctx); + dma_fence_free(&fence->base); +} + static void pvr_queue_fence_release(struct dma_fence *f) { struct pvr_queue_fence *fence = container_of(f, struct pvr_queue_fence, base); + struct pvr_device *pvr_dev = fence->queue->ctx->pvr_dev; - pvr_context_put(fence->queue->ctx); - dma_fence_free(f); + queue_work(pvr_dev->sched_wq, &fence->release_work); } static const char * @@ -268,6 +276,7 @@ pvr_queue_fence_init(struct dma_fence *f, pvr_context_get(queue->ctx); fence->queue = queue; + INIT_WORK(&fence->release_work, pvr_queue_fence_release_work); dma_fence_init(&fence->base, fence_ops, &fence_ctx->lock, fence_ctx->id, atomic_inc_return(&fence_ctx->seqno)); -- cgit v1.2.3 From 68c3de7f707e8a70e0a6d8087cf0fe4a3d5dbfb0 Mon Sep 17 00:00:00 2001 From: Brendan King Date: Wed, 26 Feb 2025 15:43:54 +0000 Subject: drm/imagination: only init job done fences once Ensure job done fences are only initialised once. This fixes a memory manager not clean warning from drm_mm_takedown on module unload. Cc: stable@vger.kernel.org Fixes: eaf01ee5ba28 ("drm/imagination: Implement job submission and scheduling") Signed-off-by: Brendan King Reviewed-by: Matt Coster Link: https://patchwork.freedesktop.org/patch/msgid/20250226-init-done-fences-once-v2-1-c1b2f556b329@imgtec.com Signed-off-by: Matt Coster --- drivers/gpu/drm/imagination/pvr_queue.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/gpu/drm/imagination/pvr_queue.c') diff --git a/drivers/gpu/drm/imagination/pvr_queue.c b/drivers/gpu/drm/imagination/pvr_queue.c index f3f1c5212df7..43411be930a2 100644 --- a/drivers/gpu/drm/imagination/pvr_queue.c +++ b/drivers/gpu/drm/imagination/pvr_queue.c @@ -313,8 +313,9 @@ pvr_queue_cccb_fence_init(struct dma_fence *fence, struct pvr_queue *queue) static void pvr_queue_job_fence_init(struct dma_fence *fence, struct pvr_queue *queue) { - pvr_queue_fence_init(fence, queue, &pvr_queue_job_fence_ops, - &queue->job_fence_ctx); + if (!fence->ops) + pvr_queue_fence_init(fence, queue, &pvr_queue_job_fence_ops, + &queue->job_fence_ctx); } /** -- cgit v1.2.3