Subject: CVE-2024-36024: drm/amd/display: Disable idle reallow as part of command/gpint execution

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

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

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

drm/amd/display: Disable idle reallow as part of command/gpint execution

[Why]
Workaroud for a race condition where DMCUB is in the process of
committing to IPS1 during the handshake causing us to miss the
transition into IPS2 and touch the INBOX1 RPTR causing a HW hang.

[How]
Disable the reallow to ensure that we have enough of a gap between entry
and exit and we're not seeing back-to-back wake_and_executes.

The Linux kernel CVE team has assigned CVE-2024-36024 to this issue.

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

	Fixed in 6.8.6 with commit 2aac38744561
	Fixed in 6.9 with commit 6226a5aa7737

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-2024-36024
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/dc.h
	drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
	drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.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/2aac387445610d6dfd681f5214388e86f5677ef7
	https://git.kernel.org/stable/c/6226a5aa77370329e01ee8abe50a95e60618ce97