This is a note to let you know that I've just added the patch titled drm/mediatek: Check if fb is null to the 5.11-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-mediatek-check-if-fb-is-null.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ea478f99e0d693ea6b7fa0af6296d1e26313c466 Author: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx> Date: Mon Jan 11 15:43:44 2021 +0800 drm/mediatek: Check if fb is null [ Upstream commit b1d685b6467ac0d98fc63989f71b4ca9186be5d4 ] It's possible that state->base.fb is null. Add a check before access its format. Fixes: b6b1bb980ec4 ("drm/mediatek: Turn off Alpha bit when plane format has no alpha") Signed-off-by: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx> Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c index 74ef6fc0528b6..523716e3c278a 100644 --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c @@ -267,7 +267,7 @@ static void mtk_ovl_layer_config(struct mtk_ddp_comp *comp, unsigned int idx, } con = ovl_fmt_convert(ovl, fmt); - if (state->base.fb->format->has_alpha) + if (state->base.fb && state->base.fb->format->has_alpha) con |= OVL_CON_AEN | OVL_CON_ALPHA; if (pending->rotation & DRM_MODE_REFLECT_Y) {