From: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp
[ Upstream commit b30b61ff6b1dc37f276cf56a8328b80086a3ffca ]
syzbot is hitting a lockdep warning [1] because flush_work() is called without INIT_WORK() after kzalloc() at vkms_atomic_crtc_reset().
Commit 6c234fe37c57627a ("drm/vkms: Implement CRC debugfs API") added INIT_WORK() to only vkms_atomic_crtc_duplicate_state() side. Assuming that lifecycle of crc_work is appropriately managed, fix this problem by adding INIT_WORK() to vkms_atomic_crtc_reset() side.
[1] https://syzkaller.appspot.com/bug?id=a5954455fcfa51c29ca2ab55b203076337e1c77...
Reported-and-tested-by: syzbot syzbot+12f1b031b6da017e34f8@syzkaller.appspotmail.com Signed-off-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Reviewed-by: Shayenne Moura shayenneluzmoura@gmail.com Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch Link: https://patchwork.freedesktop.org/patch/msgid/1547829823-9877-1-git-send-ema... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/vkms/vkms_crtc.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c index a0bef7de9df7..1054f535178a 100644 --- a/drivers/gpu/drm/vkms/vkms_crtc.c +++ b/drivers/gpu/drm/vkms/vkms_crtc.c @@ -95,6 +95,7 @@ static void vkms_atomic_crtc_reset(struct drm_crtc *crtc) vkms_state = kzalloc(sizeof(*vkms_state), GFP_KERNEL); if (!vkms_state) return; + INIT_WORK(&vkms_state->crc_work, vkms_crc_work_handle);
crtc->state = &vkms_state->base; crtc->state->crtc = crtc;