Chris Wilson 39b4d07aa3 drm: Hold the mutex when dropping the last GEM reference (v2) ... In order to be fully threadsafe we need to check that the drm_gem_object refcount is still 0 after acquiring the mutex in order to call the free function. Otherwise, we may encounter scenarios like: Thread A: Thread B: drm_gem_close unreference_unlocked kref_put mutex_lock ... i915_gem_evict ... kref_get -> BUG ... i915_gem_unbind ... kref_put ... i915_gem_object_free ... mutex_unlock mutex_lock i915_gem_object_free -> BUG i915_gem_object_unbind kfree mutex_unlock Note that no driver is currently using the free_unlocked vfunc and it is scheduled for removal, hasten that process. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=30454 Reported-and-Tested-by: Magnus Kessler <Magnus.Kessler@gmx.net> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>		2010-10-01 21:08:45 +10:00
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drm	drm: Hold the mutex when dropping the last GEM reference (v2)	2010-10-01 21:08:45 +10:00
vga	vgaarb: trivial fix	2010-09-24 10:13:44 +10:00
Makefile	PCI/GPU: implement VGA arbitration on Linux	2009-09-09 13:29:36 -07:00