1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/radeon_semaphore.c b/drivers/gpu/drm/radeon/radeon_semaphore.c
index 97f3ece81cd2..8dcc20f53d73 100644
--- a/drivers/gpu/drm/radeon/radeon_semaphore.c
+++ b/drivers/gpu/drm/radeon/radeon_semaphore.c
@@ -95,6 +95,10 @@ int radeon_semaphore_sync_rings(struct radeon_device *rdev,
         /* we assume caller has already allocated space on waiters ring */
         radeon_semaphore_emit_wait(rdev, waiter, semaphore);
 
+        /* for debugging lockup only, used by sysfs debug files */
+        rdev->ring[signaler].last_semaphore_signal_addr = semaphore->gpu_addr;
+        rdev->ring[waiter].last_semaphore_wait_addr = semaphore->gpu_addr;
+
         return 0;
 }