Re: [PATCH v5.10] drm/amd/display: Wake DMCUB before executing GPINT commands

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Apr 16, 2024 at 02:43:47AM +0000, Zhu Wang wrote:
> From: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> 
> stable inclusion
> from stable-v6.7.3
> commit 	2ef98c6d753a7 ("drm/amd/display: Wake DMCUB before executing GPINT commands")
> category: bugfix
> bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9BV4C
> CVE: CVE-2023-52624
> 
> Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2ef98c6d753a744e333b7e34b9cf687040fba57d
> 
> --------------------------------
> 
> [ Upstream commit e5ffd1263dd5b ("drm/amd/display: Wake DMCUB before executing GPINT commands") ]
> 
> [Why]
> DMCUB can be in idle when we attempt to interface with the HW through
> the GPINT mailbox resulting in a system hang.
> 
> [How]
> Add dc_wake_and_execute_gpint() to wrap the wake, execute, sleep
> sequence.
> 
> If the GPINT executes successfully then DMCUB will be put back into
> sleep after the optional response is returned.
> 
> It functions similar to the inbox command interface.
> 
> Cc: Mario Limonciello <mario.limonciello@amd.com>
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: stable@vger.kernel.org
> Reviewed-by: Hansen Dsouza <hansen.dsouza@amd.com>
> Acked-by: Wayne Lin <wayne.lin@amd.com>
> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
> 
> This patch comes from following commits:
> 
>  115c7e7f0501 ("drm/amd/display: Add psr get_state call")
>  1d496907f1c5 ("drm/amd/display: Engage PSR synchronously")
>  34ba432c946d ("drm/amd/display: [FW Promotion] Release 0.0.44")
>  672251b223c1 ("drm/amd/display: [FW Promotion] Release 0.0.40")
>  04f3c88f0955 ("drm/amd/display: Retry getting PSR state if command times out")
>  b30eda8d416c ("drm/amd/display: Add ETW log to dmub_psr_get_state")
>  f59a66c1915e ("drm/amd/display: use do-while-0 for DC_TRACE_LEVEL_MESSAGE()")
>  e97cc04fe0fb ("drm/amd/display: refactor dmub commands into single function")
>  522b9a5d5852 ("drm/amd/display: drain dmub inbox if queue is full")
>  9dce8c2a5f1b ("drm/amd/display: [FW Promotion] Release 0.0.161.0")
>  276641775848 ("drm/amd/display: [FW Promotion] Release 0.0.162.0")
>  8774029f76b9 ("drm/amd/display: Add DCN35 CLK_MGR")
>  65138eb72e1f ("drm/amd/display: Add DCN35 DMUB")
>  dc01c4b79bfe ("drm/amd/display: Update driver and IPS interop")
>  5b7954272ae9 ("drm/amd/display: [FW Promotion] Release 0.0.183.0")
>  da2d16fcdda3 ("drm/amd/display: Fix IPS handshake for idle optimizations")
>  5e8a0d3598b4 ("drm/amd/display: Negate IPS allow and commit bits")
>  820c3870c491 ("drm/amd/display: Refactor DMCUB enter/exit idle interface")
>  2ef98c6d753a ("drm/amd/display: Wake DMCUB before executing GPINT commands")
> 
> Signed-off-by: Zhu Wang <wangzhu9@huawei.com>

I'm confused, what are we supposed to do with this?

greg k-h