This is a note to let you know that I've just added the patch titled
drm/display/dp_mst: Fix payload addition on a disconnected sink
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-display-dp_mst-fix-payload-addition-on-a-disconnected-sink.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 33f960e23c29d113fe3193e0bdc19ac4f3776f20 Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@xxxxxxxxx>
Date: Wed, 14 Dec 2022 20:42:58 +0200
Subject: drm/display/dp_mst: Fix payload addition on a disconnected sink
From: Imre Deak <imre.deak@xxxxxxxxx>
commit 33f960e23c29d113fe3193e0bdc19ac4f3776f20 upstream.
If an MST stream is enabled on a disconnected sink, the payload for the
stream is not created and the MST manager's payload count/next start VC
slot is not updated. Since the payload's start VC slot may still contain
a valid value (!= -1) the subsequent disabling of such a stream could
cause an incorrect decrease of the payload count/next start VC slot in
drm_dp_remove_payload() and hence later payload additions will fail.
Fix the above by marking the payload as invalid in the above case, so
that it's skipped during payload removal. While at it add a debug print
for this case.
Cc: Lyude Paul <lyude@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v6.1+
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
Reviewed-by: Lyude Paul <lyude@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20221214184258.2869417-3-imre.deak@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/display/drm_dp_mst_topology.c | 7 ++++++-
1 file changed, 6 insertions(+), 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 01350510244f..5861b0a6247b 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -3309,8 +3309,13 @@ int drm_dp_add_payload_part1(struct drm_dp_mst_topology_mgr *mgr,
int ret;
port = drm_dp_mst_topology_get_port_validated(mgr, payload->port);
- if (!port)
+ if (!port) {
+ drm_dbg_kms(mgr->dev,
+ "VCPI %d for port %p not in topology, not creating a payload\n",
+ payload->vcpi, payload->port);
+ payload->vc_start_slot = -1;
return 0;
+ }
if (mgr->payload_count == 0)
mgr->next_start_slot = mst_state->start_slot;
--
2.39.2
Patches currently in stable-queue which might be from imre.deak@xxxxxxxxx are
queue-6.1/drm-i915-dp_mst-add-the-mst-topology-state-for-modesetted-crtcs.patch
queue-6.1/drm-display-dp_mst-fix-down-message-handling-after-a-packet-reception-error.patch
queue-6.1/drm-display-dp_mst-fix-down-up-message-handling-after-sink-disconnect.patch
queue-6.1/drm-i915-fix-system-suspend-without-fbdev-being-initialized.patch
queue-6.1/drm-display-dp_mst-fix-payload-addition-on-a-disconnected-sink.patch
queue-6.1/drm-display-dp_mst-add-drm_atomic_get_old_mst_topology_state.patch
