The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x d63d81094d208abb20fc444514b2d9ec2f4b7c4e # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024073031-survivor-unaudited-6efd@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

d63d81094d20 ("drm/dp_mst: Fix all mstb marked as not probed after suspend/resume")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From d63d81094d208abb20fc444514b2d9ec2f4b7c4e Mon Sep 17 00:00:00 2001 From: Wayne Lin Wayne.Lin@amd.com Date: Wed, 26 Jun 2024 16:48:23 +0800 Subject: [PATCH] drm/dp_mst: Fix all mstb marked as not probed after suspend/resume

[Why] After supend/resume, with topology unchanged, observe that link_address_sent of all mstb are marked as false even the topology probing is done without any error.

It is caused by wrongly also include "ret == 0" case as a probing failure case.

[How] Remove inappropriate checking conditions.

Cc: Lyude Paul lyude@redhat.com Cc: Harry Wentland hwentlan@amd.com Cc: Jani Nikula jani.nikula@intel.com Cc: Imre Deak imre.deak@intel.com Cc: Daniel Vetter daniel@ffwll.ch Cc: stable@vger.kernel.org Fixes: 37dfdc55ffeb ("drm/dp_mst: Cleanup drm_dp_send_link_address() a bit") Signed-off-by: Wayne Lin Wayne.Lin@amd.com Reviewed-by: Lyude Paul lyude@redhat.com Signed-off-by: Lyude Paul lyude@redhat.com Link: https://patchwork.freedesktop.org/patch/msgid/20240626084825.878565-2-Wayne....

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index 7f8e1cfbe19d..68831f4e502a 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -2929,7 +2929,7 @@ static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr,

/* FIXME: Actually do some real error handling here */ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); - if (ret <= 0) { + if (ret < 0) { drm_err(mgr->dev, "Sending link address failed with %d\n", ret); goto out; } @@ -2981,7 +2981,7 @@ static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, mutex_unlock(&mgr->lock);

out: - if (ret <= 0) + if (ret < 0) mstb->link_address_sent = false; kfree(txmsg); return ret < 0 ? ret : changed;