From f1029e7ead9a5f13ef040dfbe1473b975f927b41 Mon Sep 17 00:00:00 2001 From: Nicholas Kazlauskas Date: Thu, 2 Apr 2020 15:59:44 -0400 Subject: [PATCH] drm/amd/display: Avoid NULL pointer in set_backlight when ABM is NULL [Why] On ASIC without ABM support (most dGPU) we run into a null pointer dereference when attempting to set the backlight level. [How] This function requires ABM, so fix up the condition to only allow DMCU to be optional. Signed-off-by: Nicholas Kazlauskas Reviewed-by: Wyatt Wood Acked-by: Rodrigo Siqueira Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index 1c5c11d6347e0..a926c1c3f57da 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -2462,8 +2462,7 @@ bool dc_link_set_backlight_level(const struct dc_link *link, int i; DC_LOGGER_INIT(link->ctx->logger); - if ((dmcu == NULL && abm == NULL) || - (abm->funcs->set_backlight_level_pwm == NULL)) + if (abm == NULL || (abm->funcs->set_backlight_level_pwm == NULL)) return false; if (dmcu) -- 2.30.2