Re: [PATCH for-4.20] Revert "drm/rockchip: Allow driver to be shutdown on reboot/kexec"

[Heiko Stuebner]

Am Mittwoch, 5. Dezember 2018, 19:16:57 CET schrieb Brian Norris:
> This reverts commit 7f3ef5dedb146e3d5063b6845781ad1bb59b92b5.
> 
> It causes new warnings [1] on shutdown when running the Google Kevin or
> Scarlet (RK3399) boards under Chrome OS. Presumably our usage of DRM is
> different than what Marc and Heiko test.
> 
> We're looking at a different approach (e.g., [2]) to replace this, but
> IMO the revert should be taken first, as it already propagated to
> -stable.
> 
> [1] Report here:
> http://lkml.kernel.org/lkml/20181205030127.GA200921@xxxxxxxxxx
> 
> WARNING: CPU: 4 PID: 2035 at drivers/gpu/drm/drm_mode_config.c:477 drm_mode_config_cleanup+0x1c4/0x294
> ...
>  Call trace:
>   drm_mode_config_cleanup+0x1c4/0x294
>   rockchip_drm_unbind+0x4c/0x8c
>   component_master_del+0x88/0xb8
>   rockchip_drm_platform_remove+0x2c/0x44
>   rockchip_drm_platform_shutdown+0x20/0x2c
>   platform_drv_shutdown+0x2c/0x38
>   device_shutdown+0x164/0x1b8
>   kernel_restart_prepare+0x40/0x48
>   kernel_restart+0x20/0x68
> ...
>  Memory manager not clean during takedown.
>  WARNING: CPU: 4 PID: 2035 at drivers/gpu/drm/drm_mm.c:950 drm_mm_takedown+0x34/0x44
> ...
>   drm_mm_takedown+0x34/0x44
>   rockchip_drm_unbind+0x64/0x8c
>   component_master_del+0x88/0xb8
>   rockchip_drm_platform_remove+0x2c/0x44
>   rockchip_drm_platform_shutdown+0x20/0x2c
>   platform_drv_shutdown+0x2c/0x38
>   device_shutdown+0x164/0x1b8
>   kernel_restart_prepare+0x40/0x48
>   kernel_restart+0x20/0x68
> ...
> 
> [2] https://patchwork.kernel.org/patch/10556151/
>     https://www.spinics.net/lists/linux-rockchip/msg21342.html
>     [PATCH] drm/rockchip: shutdown drm subsystem on shutdown
> 
> Fixes: 7f3ef5dedb14 ("drm/rockchip: Allow driver to be shutdown on reboot/kexec")
> Cc: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx>
> Cc: Robin Murphy <robin.murphy@xxxxxxx>
> Cc: Vicente Bergas <vicencb@xxxxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> Cc: Heiko Stuebner <heiko@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>

So, I've applied this revert to drm-misc-fixes now, so it should still
land in 4.20-rc.

I'll resurrect Vicentes patch for a later regular inclusion as well,
but with more testing involved.


Heiko