drm/i915: Fix use of invalid array size for ring->sync_seqno

There are I915_NUM_RINGS-1 inter-ring synchronisation counters, but we
were clearing I915_NUM_RINGS of them. Oops.

Reported-by: Jiri Slaby <jirislaby@gmail.com>
Tested-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 3dfc848..812b97b 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1857,7 +1857,7 @@ i915_gem_retire_requests_ring(struct drm_device *dev,
 
        seqno = ring->get_seqno(ring);
 
-       for (i = 0; i < I915_NUM_RINGS; i++)
+       for (i = 0; i < ARRAY_SIZE(ring->sync_seqno); i++)
                if (seqno >= ring->sync_seqno[i])
                        ring->sync_seqno[i] = 0;
 

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index dcfdf41..d2f445e 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1175,7 +1175,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
                goto err;
 
        seqno = i915_gem_next_request_seqno(dev, ring);
-       for (i = 0; i < I915_NUM_RINGS-1; i++) {
+       for (i = 0; i < ARRAY_SIZE(ring->sync_seqno); i++) {
                if (seqno < ring->sync_seqno[i]) {
                        /* The GPU can not handle its semaphore value wrapping,
                         * so every billion or so execbuffers, we need to stall