On Mon, Nov 23, 2015 at 6:40 PM, Russell King - ARM Linux linux@arm.linux.org.uk wrote:
On Mon, Nov 23, 2015 at 10:32:46AM +0100, Daniel Vetter wrote:
diff --git a/drivers/gpu/drm/armada/armada_gem.c b/drivers/gpu/drm/armada/armada_gem.c index e3a86b96af2a..a43690ab18b9 100644 --- a/drivers/gpu/drm/armada/armada_gem.c +++ b/drivers/gpu/drm/armada/armada_gem.c @@ -46,7 +46,7 @@ static size_t roundup_gem_size(size_t size) return roundup(size, PAGE_SIZE); }
-/* dev->struct_mutex is held here */ +/* dev_priv->linear_lock is held here */ void armada_gem_free_object(struct drm_gem_object *obj)
This is wrong (unless there's changes which I'm not aware of.)
This function is called from drm_gem_object_free(), which is called from drm_gem_object_unreference(), both of which contain:
WARN_ON(!mutex_is_locked(&dev->struct_mutex));Now, unless you're changing the conditions on which drm_gem_object_unreference() to be under dev_priv->linear_lock, the above comment becomes misleading.
It'd also need drm_gem_object_unreference_unlocked() to become per- driver, so it can take dev_priv->linear_lock, and I don't see anything in the patches which I've received which does that.
So, I suspect the new comment is basically false.
Well the patch is false. I should have grabbed the new dev_priv->linear_lock around the cleanup functions in armada_gem_free_object. Which is possible since armada never calls an gem unref function while holding the new lock. Sorry for not double-checking what I've done, I'll revise. -Daniel