drm/i915: Make dev_priv->mm.wedged an atomic_t
There is a very real possibility that multiple CPUs will notice that the
GPU is wedged. This introduces all sorts of potential race conditions.
Make the wedged flag atomic to mitigate this risk.
Signed-off-by: Ben Gamari <bgamari.foss@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 579b3b04..f0f6f668 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1712,7 +1712,7 @@
retiring_seqno = request->seqno;
if (i915_seqno_passed(seqno, retiring_seqno) ||
- dev_priv->mm.wedged) {
+ atomic_read(&dev_priv->mm.wedged)) {
i915_gem_retire_request(dev, request);
list_del(&request->list);
@@ -1754,7 +1754,7 @@
BUG_ON(seqno == 0);
- if (dev_priv->mm.wedged)
+ if (atomic_read(&dev_priv->mm.wedged))
return -EIO;
if (!i915_seqno_passed(i915_get_gem_seqno(dev), seqno)) {
@@ -1774,11 +1774,11 @@
ret = wait_event_interruptible(dev_priv->irq_queue,
i915_seqno_passed(i915_get_gem_seqno(dev),
seqno) ||
- dev_priv->mm.wedged);
+ atomic_read(&dev_priv->mm.wedged));
i915_user_irq_put(dev);
dev_priv->mm.waiting_gem_seqno = 0;
}
- if (dev_priv->mm.wedged)
+ if (atomic_read(&dev_priv->mm.wedged))
ret = -EIO;
if (ret && ret != -ERESTARTSYS)
@@ -3359,7 +3359,7 @@
i915_verify_inactive(dev, __FILE__, __LINE__);
- if (dev_priv->mm.wedged) {
+ if (atomic_read(&dev_priv->mm.wedged)) {
DRM_ERROR("Execbuf while wedged\n");
mutex_unlock(&dev->struct_mutex);
ret = -EIO;
@@ -3929,7 +3929,7 @@
if (last_seqno == cur_seqno) {
if (stuck++ > 100) {
DRM_ERROR("hardware wedged\n");
- dev_priv->mm.wedged = 1;
+ atomic_set(&dev_priv->mm.wedged, 1);
DRM_WAKEUP(&dev_priv->irq_queue);
break;
}
@@ -3942,7 +3942,7 @@
i915_gem_retire_requests(dev);
spin_lock(&dev_priv->mm.active_list_lock);
- if (!dev_priv->mm.wedged) {
+ if (!atomic_read(&dev_priv->mm.wedged)) {
/* Active and flushing should now be empty as we've
* waited for a sequence higher than any pending execbuffer
*/
@@ -4204,9 +4204,9 @@
if (drm_core_check_feature(dev, DRIVER_MODESET))
return 0;
- if (dev_priv->mm.wedged) {
+ if (atomic_read(&dev_priv->mm.wedged)) {
DRM_ERROR("Reenabling wedged hardware, good luck\n");
- dev_priv->mm.wedged = 0;
+ atomic_set(&dev_priv->mm.wedged, 0);
}
mutex_lock(&dev->struct_mutex);