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In that situation, we do not call cmdq_pkt_create(). During the cleanup, we need to check if the "mtk_crtc->cmdq_client.chan" is NULL first before calling cmdq_pkt_destroy(). Calling cmdq_pkt_destroy() is unnecessary if we didn't call cmdq_pkt_create() and it will result in a NULL pointer dereference. Fixes: 7627122fd1c0 ("drm/mediatek: Add cmdq_handle in mtk_crtc") Signed-off-by: Dan Carpenter Reviewed-by: AngeloGioacchino Del Regno --- drivers/gpu/drm/mediatek/mtk_crtc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c index 175b00e5a253..c15013792583 100644 --- a/drivers/gpu/drm/mediatek/mtk_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c @@ -127,9 +127,8 @@ static void mtk_crtc_destroy(struct drm_crtc *crtc) mtk_mutex_put(mtk_crtc->mutex); #if IS_REACHABLE(CONFIG_MTK_CMDQ) - cmdq_pkt_destroy(&mtk_crtc->cmdq_client, &mtk_crtc->cmdq_handle); - if (mtk_crtc->cmdq_client.chan) { + cmdq_pkt_destroy(&mtk_crtc->cmdq_client, &mtk_crtc->cmdq_handle); mbox_free_channel(mtk_crtc->cmdq_client.chan); mtk_crtc->cmdq_client.chan = NULL; }