From 244594c5f5c80c6505b4dd6a94bd1b847d24f38e Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Sat, 19 Jan 2019 01:43:43 +0900 Subject: [PATCH] drm/vkms: Fix flush_work() without INIT_WORK(). commit b30b61ff6b1dc37f276cf56a8328b80086a3ffca upstream. 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=a5954455fcfa51c29ca2ab55b203076337e1c770 Reported-and-tested-by: syzbot Signed-off-by: Tetsuo Handa Reviewed-by: Shayenne Moura Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/1547829823-9877-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman --- 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 eb56ee893761..e747a7d16739 100644 --- a/drivers/gpu/drm/vkms/vkms_crtc.c +++ b/drivers/gpu/drm/vkms/vkms_crtc.c @@ -98,6 +98,7 @@ 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; -- 2.11.4.GIT