From: Imre Deak <imre.deak@intel.com>
Date: Wed, 14 Dec 2022 20:42:57 +0200
Subject: [PATCH] drm/display/dp_mst: Fix down message handling after a packet
 reception error
References: bsc#1012628
Patch-mainline: 6.2.5
Git-commit: 1241aedb6b5c7a5a8ad73e5eb3a41cfe18a3e00e

commit 1241aedb6b5c7a5a8ad73e5eb3a41cfe18a3e00e upstream.

After an error during receiving a packet for a multi-packet DP MST
sideband message, the state tracking which packets have been received
already is not reset. This prevents the reception of subsequent down
messages (due to the pending message not yet completed with an
end-of-message-transfer packet).

Fix the above by resetting the reception state after a packet error.

Cc: Lyude Paul <lyude@redhat.com>
Cc: <stable@vger.kernel.org> # v3.17+
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221214184258.2869417-2-imre.deak@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/gpu/drm/display/drm_dp_mst_topology.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index 82d1473a..d77858c7 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -3859,7 +3859,7 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 	struct drm_dp_sideband_msg_rx *msg = &mgr->down_rep_recv;
 
 	if (!drm_dp_get_one_sb_msg(mgr, false, &mstb))
-		goto out;
+		goto out_clear_reply;
 
 	/* Multi-packet message transmission, don't clear the reply */
 	if (!msg->have_eomt)
-- 
2.35.3