drm/amd/display: NULL pointer hang

[Why]
In dc_link_dp_set_test_pattern, we assume all pipes have a stream, which
can cause null pointer dereference.

[How]
Add a null pointer check before accessing stream.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Qingqing Zhuo 2020-12-09 18:04:04 -05:00 committed by Alex Deucher
parent f14a5c34d1
commit 73644143b3

View File

@ -3992,7 +3992,7 @@ bool dc_link_dp_set_test_pattern(
unsigned int cust_pattern_size)
{
struct pipe_ctx *pipes = link->dc->current_state->res_ctx.pipe_ctx;
struct pipe_ctx *pipe_ctx = &pipes[0];
struct pipe_ctx *pipe_ctx = NULL;
unsigned int lane;
unsigned int i;
unsigned char link_qual_pattern[LANE_COUNT_DP_MAX] = {0};
@ -4002,12 +4002,18 @@ bool dc_link_dp_set_test_pattern(
memset(&training_pattern, 0, sizeof(training_pattern));
for (i = 0; i < MAX_PIPES; i++) {
if (pipes[i].stream == NULL)
continue;
if (pipes[i].stream->link == link && !pipes[i].top_pipe && !pipes[i].prev_odm_pipe) {
pipe_ctx = &pipes[i];
break;
}
}
if (pipe_ctx == NULL)
return false;
/* Reset CRTC Test Pattern if it is currently running and request is VideoMode */
if (link->test_pattern_enabled && test_pattern ==
DP_TEST_PATTERN_VIDEO_MODE) {