In detect_link_and_local_sink(), prev_sink is retained via
dc_sink_retain() to keep it alive while probing for a new sink.
When the link type is DisplayPort and the USB-C alt mode
transition times out (i.e. wait_for_entering_dp_alt_mode()
returns false), the function returns false without releasing
the prev_sink reference acquired earlier. All other error paths
after the retain properly release the reference.
Fix this by calling dc_sink_release(prev_sink) before returning
on the DP alt mode timeout path.
Cc: stable@vger.kernel.org
Fixes: 54618888d1ea ("drm/amd/display: break down dc_link.c")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
drivers/gpu/drm/amd/display/dc/link/link_detection.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/link/link_detection.c b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
index 794dd6a95918..4473d93b783a 100644
--- a/drivers/gpu/drm/amd/display/dc/link/link_detection.c
+++ b/drivers/gpu/drm/amd/display/dc/link/link_detection.c
@@ -1069,8 +1069,10 @@ static bool detect_link_and_local_sink(struct dc_link *link,
link->link_enc->features.flags.bits.DP_IS_USB_C == 1) {
/* if alt mode times out, return false */
- if (!wait_for_entering_dp_alt_mode(link))
+ if (!wait_for_entering_dp_alt_mode(link)) {
+ dc_sink_release(prev_sink);
return false;
+ }
}
if (!detect_dp(link, &sink_caps, reason)) {
--
2.34.1