On 6/15/22 10:01 AM, Rob Clark wrote:
From: Rob Clark <robdclark@xxxxxxxxxxxx>
Prior to the last commit, this could result in setting the GPU
written fence value back to an older value, if we had missed
updating completed_fence prior to suspend. This was mostly
harmless as the GPU would eventually overwrite it again with
the correct value. But we should just not do this. Instead
just leave a sanity check that the fence looks plausible (in
case the GPU scribbled on memory).
Reported-by: Steev Klimaszewski <steev@xxxxxxxx>
Fixes: 95d1deb02a9c ("drm/msm/gem: Add fenced vma unpin")
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/msm/adreno/adreno_gpu.c | 11 ++++++++---
drivers/gpu/drm/msm/msm_gpu.c | 2 +-
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index e1aef4875e2f..dd044d557c7c 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -498,10 +498,15 @@ int adreno_hw_init(struct msm_gpu *gpu)
ring->cur = ring->start;
ring->next = ring->start;
-
- /* reset completed fence seqno: */
- ring->memptrs->fence = ring->fctx->completed_fence;
ring->memptrs->rptr = 0;
+
+ /* Detect and clean up an impossible fence, ie. if GPU managed
+ * to scribble something invalid, we don't want that to confuse
+ * us into mistakingly believing that submits have completed.
+ */
+ if (fence_before(ring->fctx->last_fence, ring->memptrs->fence)) {
+ ring->memptrs->fence = ring->fctx->last_fence;
+ }
}
return 0;
diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index b61078f0cd0f..8c00f9187c03 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -430,7 +430,7 @@ static void recover_worker(struct kthread_work *work)
* one more to clear the faulting submit
*/
if (ring == cur_ring)
- fence++;
+ ring->memptrs->fence = ++fence;
msm_update_fence(ring->fctx, fence);
}
Tested on the Lenovo Yoga C630
Tested-by: Steev Klimaszewski <steev@xxxxxxxx>
