This is a note to let you know that I've just added the patch titled
drm/amd/display: explicitly set is_dsc_supported to false before use
to the 5.15-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-amd-display-explicitly-set-is_dsc_supported-to-false-before-use.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 63ad5371cd1e379519395c49a4b6a652c36c98e5 Mon Sep 17 00:00:00 2001
From: Mario Limonciello <mario.limonciello@xxxxxxx>
Date: Wed, 5 Jan 2022 12:48:16 -0600
Subject: drm/amd/display: explicitly set is_dsc_supported to false before use
From: Mario Limonciello <mario.limonciello@xxxxxxx>
commit 63ad5371cd1e379519395c49a4b6a652c36c98e5 upstream.
When UBSAN is enabled a case is shown on unplugging the display that
this variable hasn't been initialized by `update_dsc_caps`, presumably
when the display was unplugged it wasn't copied from the DPCD.
Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1956497
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -5604,6 +5604,7 @@ static void update_dsc_caps(struct amdgp
struct dsc_dec_dpcd_caps *dsc_caps)
{
stream->timing.flags.DSC = 0;
+ dsc_caps->is_dsc_supported = false;
if (aconnector->dc_link && sink->sink_signal == SIGNAL_TYPE_DISPLAY_PORT) {
dc_dsc_parse_dsc_dpcd(aconnector->dc_link->ctx->dc,
Patches currently in stable-queue which might be from mario.limonciello@xxxxxxx are
queue-5.15/drm-amd-display-explicitly-set-is_dsc_supported-to-false-before-use.patch
