This is a note to let you know that I've just added the patch titled drm: Release driver tracking before making the object available again to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-release-driver-tracking-before-making-the-object-available-again.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From fe4600a548f2763dec91b3b27a1245c370ceee2a Mon Sep 17 00:00:00 2001 From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Date: Sat, 19 Aug 2017 13:05:58 +0100 Subject: drm: Release driver tracking before making the object available again MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> commit fe4600a548f2763dec91b3b27a1245c370ceee2a upstream. This is the same bug as we fixed in commit f6cd7daecff5 ("drm: Release driver references to handle before making it available again"), but now the exposure is via the PRIME lookup tables. If we remove the object/handle from the PRIME lut, then a new request for the same object/fd will generate a new handle, thus for a short window that object is known to userspace by two different handles. Fix this by releasing the driver tracking before PRIME. Fixes: 0ff926c7d4f0 ("drm/prime: add exported buffers to current fprivs imported buffer list (v2)") Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: David Airlie <airlied@xxxxxxxx> Cc: Daniel Vetter <daniel.vetter@xxxxxxxxx> Cc: Rob Clark <robdclark@xxxxxxxxx> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Thierry Reding <treding@xxxxxxxxxx> Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Signed-off-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20170819120558.6465-1-chris@xxxxxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/drm_gem.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -255,13 +255,13 @@ drm_gem_object_release_handle(int id, vo struct drm_gem_object *obj = ptr; struct drm_device *dev = obj->dev; + if (dev->driver->gem_close_object) + dev->driver->gem_close_object(obj, file_priv); + if (drm_core_check_feature(dev, DRIVER_PRIME)) drm_gem_remove_prime_handles(obj, file_priv); drm_vma_node_revoke(&obj->vma_node, file_priv); - if (dev->driver->gem_close_object) - dev->driver->gem_close_object(obj, file_priv); - drm_gem_object_handle_unreference_unlocked(obj); return 0; Patches currently in stable-queue which might be from chris@xxxxxxxxxxxxxxxxxx are queue-4.9/drm-release-driver-tracking-before-making-the-object-available-again.patch