]> git.baikalelectronics.ru Git - kernel.git/commit
drm: damage_helper: Fix race checking plane->state->fb
authorSean Paul <seanpaul@chromium.org>
Wed, 4 Sep 2019 20:29:13 +0000 (16:29 -0400)
committerSean Paul <seanpaul@chromium.org>
Tue, 8 Oct 2019 13:41:06 +0000 (09:41 -0400)
commitc7e5d3b3144ab218abad717aeddc7ec331edd928
tree3e5489031e4a32d7468798d33dea647fee51c37b
parent1e01e78c190abcdafd824722f65a88e0a6ed30d8
drm: damage_helper: Fix race checking plane->state->fb

Since the dirtyfb ioctl doesn't give us any hints as to which plane is
scanning out the fb it's marking as damaged, we need to loop through
planes to find it.

Currently we just reach into plane state and check, but that can race
with another commit changing the fb out from under us. This patch locks
the plane before checking the fb and will release the lock if the plane
is not displaying the dirty fb.

Fixes: aedceaddcd46 ("drm: Add helper to implement legacy dirtyfb")
Cc: Rob Clark <robdclark@gmail.com>
Cc: Deepak Rawat <drawat@vmware.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v5.0+
Reported-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190904202938.110207-1-sean@poorly.run
drivers/gpu/drm/drm_damage_helper.c