The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 334b56cea5d9df5989be6cf1a5898114fa70ad98 Mon Sep 17 00:00:00 2001 From: Allen Pan <allen.pan@xxxxxxx> Date: Fri, 23 Feb 2024 18:20:16 -0500 Subject: [PATCH] drm/amd/display: Add a dc_state NULL check in dc_state_release [How] Check wheather state is NULL before releasing it. Cc: Mario Limonciello <mario.limonciello@xxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Charlene Liu <charlene.liu@xxxxxxx> Acked-by: Alex Hung <alex.hung@xxxxxxx> Signed-off-by: Allen Pan <allen.pan@xxxxxxx> Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> --- drivers/gpu/drm/amd/display/dc/core/dc_state.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_state.c b/drivers/gpu/drm/amd/display/dc/core/dc_state.c index 180ac47868c22..5cc7f8da209c5 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_state.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_state.c @@ -334,7 +334,8 @@ static void dc_state_free(struct kref *kref) void dc_state_release(struct dc_state *state) { - kref_put(&state->refcount, dc_state_free); + if (state != NULL) + kref_put(&state->refcount, dc_state_free); } /* * dc_state_add_stream() - Add a new dc_stream_state to a dc_state. -- 2.43.0