drm/i915: Check for dev->primary->master before dereference.
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 <chris@chris-wilson.co.uk> Signed-off-by: Eric Anholt <eric@anholt.net>
This commit is contained in:
parent
bf5a269a4c
commit
98787c057f
1 changed files with 6 additions and 3 deletions
|
@ -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 * dev, int n, const char *caller)
|
|||
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;
|
||||
|
|
Loading…
Reference in a new issue