drm/amdgpu: Fix display freezing issue when resizing apps

The display is freezing because the amdgpu_userq_wait_ioctl()
is waiting for a non-user queue fence(specifically, the PT update fence).

RootCause:
The resume_work is initiated by both amdgpu_userq_suspend and
amdgpu_userqueue_ensure_ev_fence at same time. The amdgpu_userq_suspend
signals a dma-fence and subsequently triggers the resume_work, which is
intended to replace the existing fence by creating new dma-fence. However,
following this, the amdgpu_userqueue_ensure_ev_fence schedules another
resume_work that generates a new dma-fence, thereby replacing the one
created by amdgpu_userq_suspend. Consequently, the original fence will
never be signaled.

Cc: Alex Deucher <[email protected]>
Cc: Christian König <[email protected]>
Cc: Shashank Sharma <[email protected]>
Cc: Sunil Khatri <[email protected]>
Reviewed-by: Christian König <[email protected]>
Reviewed-by: Shashank Sharma <[email protected]>
Signed-off-by: Arvind Yadav <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
index a02614cbda36..beae931152a3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
@@ -555,8 +555,11 @@ unlock_all:
 static void amdgpu_userqueue_resume_worker(struct work_struct *work)
 {
 	struct amdgpu_userq_mgr *uq_mgr = work_to_uq_mgr(work, resume_work.work);
+	struct amdgpu_fpriv *fpriv = uq_mgr_to_fpriv(uq_mgr);
 	int ret;
 
+	flush_work(&fpriv->evf_mgr.suspend_work.work);
+
 	mutex_lock(&uq_mgr->userq_mutex);
 
 	ret = amdgpu_userqueue_validate_bos(uq_mgr);