[PATCH 1/2] drm: Cancel drm_fb_helper_dirty_work on unload

[Chris Wilson]

We can not allow the worker to run after its fbdev, or even the module,
has been removed.

Fixes: eaa434defaca ("drm/fb-helper: Add fb_deferred_io support")
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Noralf Trønnes <noralf at tronnes.org>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Sean Paul <seanpaul at chromium.org>
Cc: dri-devel at lists.freedesktop.org
Cc: <stable at vger.kernel.org> # v4.7+
---
 drivers/gpu/drm/drm_fb_helper.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index ee7cbcd3cfeb..2d0810c9f3dc 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -860,6 +860,8 @@ void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 	if (!drm_fbdev_emulation)
 		return;
 
+	cancel_work_sync(&fb_helper->dirty_work);
+
 	mutex_lock(&kernel_fb_helper_lock);
 	if (!list_empty(&fb_helper->kernel_fb_list)) {
 		list_del(&fb_helper->kernel_fb_list);
-- 
2.11.0