Subject: CVE-2023-52634: drm/amd/display: Fix disable_otg_wa logic

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Fix disable_otg_wa logic

[Why]
When switching to another HDMI mode, we are unnecesarilly
disabling/enabling FIFO causing both HPO and DIG registers to be set at
the same time when only HPO is supposed to be set.

This can lead to a system hang the next time we change refresh rates as
there are cases when we don't disable OTG/FIFO but FIFO is enabled when
it isn't supposed to be.

[How]
Removing the enable/disable FIFO entirely.

The Linux kernel CVE team has assigned CVE-2023-52634 to this issue.

Affected and fixed versions
===========================

	Fixed in 6.7.4 with commit ce29728ef648
	Fixed in 6.8 with commit 2ce156482a6f

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2023-52634
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/ce29728ef6485a367934cc100249c66dd3cde5b6
	https://git.kernel.org/stable/c/2ce156482a6fef349d2eba98e5070c412d3af662