drm/i915: Grab dev->struct_mutex in i915_gem_pageflip_info

We could walk of a bad list otherwise when someone concurrently
unbinds stuff for fun.

I've suspected this as the root-cause behind seemingly inconsistent
state, but alas it's not.

Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Daniel Vetter 2014-06-17 22:34:37 +02:00
parent c9224faa59
commit 8a270ebf34

View File

@ -513,6 +513,11 @@ static int i915_gem_pageflip_info(struct seq_file *m, void *data)
struct drm_device *dev = node->minor->dev;
unsigned long flags;
struct intel_crtc *crtc;
int ret;
ret = mutex_lock_interruptible(&dev->struct_mutex);
if (ret)
return ret;
for_each_intel_crtc(dev, crtc) {
const char pipe = pipe_name(crtc->pipe);
@ -554,6 +559,8 @@ static int i915_gem_pageflip_info(struct seq_file *m, void *data)
spin_unlock_irqrestore(&dev->event_lock, flags);
}
mutex_unlock(&dev->struct_mutex);
return 0;
}