-stable review patch. If anyone has any objections, please let us know.
---------------------
From: Chris Wilson <[email protected]>
upstream commit: 98787c057fdefdce6230ff46f2c1105835005a4c
I've hit the occasional oops inside i915_wait_ring() with an indication of
a NULL derefence of dev->primary->master. Adding a NULL check is
consistent with the other potential users of dev->primary->master.
Signed-off-by: Chris Wilson <[email protected]>
Signed-off-by: Eric Anholt <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
drivers/gpu/drm/i915/i915_dma.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -41,7 +41,6 @@
int i915_wait_ring(struct drm_device * dev, int n, const char *caller)
{
drm_i915_private_t *dev_priv = dev->dev_private;
- struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
drm_i915_ring_buffer_t *ring = &(dev_priv->ring);
u32 acthd_reg = IS_I965G(dev) ? ACTHD_I965 : ACTHD;
u32 last_acthd = I915_READ(acthd_reg);
@@ -58,8 +57,12 @@ int i915_wait_ring(struct drm_device * d
if (ring->space >= n)
return 0;
- if (master_priv->sarea_priv)
- master_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
+ if (dev->primary->master) {
+ struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
+ if (master_priv->sarea_priv)
+ master_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
+ }
+
if (ring->head != last_head)
i = 0;