From c3b20037926e607b6cdaecbf9d3103e2ca63bc31 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 28 May 2012 22:33:02 +0100 Subject: drm/i915: Reset last_retired_head when resetting ring When we reset the ring control registers, including the HEAD and TAIL of the ring, we also need to reset associated state. In this instance, we were failing to reset the cached value of ring->last_retired_head and so upon the first request for more space following a resume would potentially (depending on a narrow race window) believe that the HEAD had advanced much further than reality. This is a regression from: commit a71d8d94525e8fd855c0466fb586ae1cb008f3a2 Author: Chris Wilson Date: Wed Feb 15 11:25:36 2012 +0000 drm/i915: Record the tail at each request and use it to estimate the head Signed-off-by: Chris Wilson Cc: stable@vger.kernel.org # 3.4 Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_ringbuffer.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index b59b6d5b7583..490df551e312 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -326,6 +326,7 @@ static int init_ring_common(struct intel_ring_buffer *ring) ring->head = I915_READ_HEAD(ring); ring->tail = I915_READ_TAIL(ring) & TAIL_ADDR; ring->space = ring_space(ring); + ring->last_retired_head = -1; } return 0; -- cgit v1.2.3