commit 9d8c094ddab0 breaks Xorg/xfce4

commit 9d8c094ddab0 breaks Xorg/xfce4

[Bert Karwatzki]

Since linux-next-20240801 starting Xorg/xfce4 fails on my MSI Alpha15 Laptop.
I bisected this to the following commit and reverting this in linux-next-20240801
fixes the issue for me. Gnome (with Xwayland) works as usual.

9d8c094ddab05db88d183ba82e23be807848cad8 is the first bad commit
commit 9d8c094ddab05db88d183ba82e23be807848cad8
Author: Mario Limonciello <mario.limonciello@amd.com>
Date:   Wed Jul 3 00:17:22 2024 -0500

    drm/amd: Add power_saving_policy drm property to eDP connectors

    When the `power_saving_policy` property is set to bit mask
    "Require color accuracy" ABM should be disabled immediately and
    any requests by sysfs to update will return an -EBUSY error.

    When the `power_saving_policy` property is set to bit mask
    "Require low latency" PSR should be disabled.

    When the property is restored to an empty bit mask ABM and PSR
    can be enabled again.

    Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
    Reviewed-by: Leo Li <sunpeng.li@amd.com>
    Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
    Link: https://patchwork.freedesktop.org/patch/msgid/20240703051722.328-3-mario.limonciello@amd.com

 drivers/gpu/drm/amd/amdgpu/amdgpu_display.c       |  4 ++++
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++-----
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |  2 ++
 3 files changed, 53 insertions(+), 5 deletions(-)

Bert Karwatzki

Re: commit 9d8c094ddab0 breaks Xorg/xfce4

[Mario Limonciello]

On 8/1/2024 11:52, Bert Karwatzki wrote:
> Since linux-next-20240801 starting Xorg/xfce4 fails on my MSI Alpha15 Laptop.
> I bisected this to the following commit and reverting this in linux-next-20240801
> fixes the issue for me. Gnome (with Xwayland) works as usual.
> 
> 9d8c094ddab05db88d183ba82e23be807848cad8 is the first bad commit
> commit 9d8c094ddab05db88d183ba82e23be807848cad8
> Author: Mario Limonciello <mario.limonciello@amd.com>
> Date:   Wed Jul 3 00:17:22 2024 -0500
> 
>      drm/amd: Add power_saving_policy drm property to eDP connectors
> 
>      When the `power_saving_policy` property is set to bit mask
>      "Require color accuracy" ABM should be disabled immediately and
>      any requests by sysfs to update will return an -EBUSY error.
> 
>      When the `power_saving_policy` property is set to bit mask
>      "Require low latency" PSR should be disabled.
> 
>      When the property is restored to an empty bit mask ABM and PSR
>      can be enabled again.
> 
>      Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>      Reviewed-by: Leo Li <sunpeng.li@amd.com>
>      Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
>      Link: https://patchwork.freedesktop.org/patch/msgid/20240703051722.328-3-mario.limonciello@amd.com
> 
>   drivers/gpu/drm/amd/amdgpu/amdgpu_display.c       |  4 ++++
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++-----
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |  2 ++
>   3 files changed, 53 insertions(+), 5 deletions(-)
> 
> Bert Karwatzki

Thanks for reporting this.  It's an odd issue!
I could reproduce it using SDDM (which uses X by "default").

Just to close the loop on it, it's been reverted for other reasons:
https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/717b432b6d55e1dcefcb5e2ec315bf66b6ab8c54

When something comes back in a different form I'll double check X again too.