The patch below does not apply to the 5.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f7d6779df642720e22bffd449e683bb8690bd3bf Mon Sep 17 00:00:00 2001

From: Guchun Chen guchun.chen@amd.com Date: Fri, 27 Aug 2021 18:31:41 +0800 Subject: [PATCH] drm/amdgpu: stop scheduler when calling hw_fini (v2) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

This gurantees no more work on the ring can be submitted to hardware in suspend/resume case, otherwise a potential race will occur and the ring will get no chance to stay empty before suspend.

v2: Call drm_sched_resubmit_job before drm_sched_start to restart jobs from the pending list.

Suggested-by: Andrey Grodzovsky andrey.grodzovsky@amd.com Suggested-by: Christian König christian.koenig@amd.com Signed-off-by: Guchun Chen guchun.chen@amd.com Reviewed-by: Christian König christian.koenig@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c index 14499f0de32d..8d682befe0d6 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c @@ -552,6 +552,9 @@ void amdgpu_fence_driver_hw_fini(struct amdgpu_device *adev) if (!ring || !ring->fence_drv.initialized) continue;

+ if (!ring->no_scheduler) + drm_sched_stop(&ring->sched, NULL); + /* You can't wait for HW to signal if it's gone */ if (!drm_dev_is_unplugged(&adev->ddev)) r = amdgpu_fence_wait_empty(ring); @@ -611,6 +614,11 @@ void amdgpu_fence_driver_hw_init(struct amdgpu_device *adev) if (!ring || !ring->fence_drv.initialized) continue;

+ if (!ring->no_scheduler) { + drm_sched_resubmit_jobs(&ring->sched); + drm_sched_start(&ring->sched, true); + } + /* enable the interrupt */ if (ring->fence_drv.irq_src) amdgpu_irq_get(adev, ring->fence_drv.irq_src,