Re: [PATCH v2 2/2] drm/fbdev: Move fbdev helpers into client library

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] drm: missing DRM_CLIENT_LIB selection in memory helpers causes linker error
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commit b0f3c606cfc59f0c56cd9be7e3349abc72f97a64
Author: Thomas Zimmermann <tzimmermann@suse.de>

drm/fbdev: Move fbdev helpers into client library

DRM's fbdev helpers are for the fbdev-emulation clients. Move them
into the client-library module. Fix include statements throughout
DRM drivers.

> diff --git a/drivers/gpu/drm/clients/Makefile b/drivers/gpu/drm/clients/Makefile
> index c16addbc327f0..1304ff358509d 100644
> --- a/drivers/gpu/drm/clients/Makefile
> +++ b/drivers/gpu/drm/clients/Makefile
> @@ -4,5 +4,6 @@ subdir-ccflags-y += -I$(src)/..
>  
>  drm_client_lib-y := drm_client_setup.o
>  drm_client_lib-$(CONFIG_DRM_CLIENT_LOG) += drm_log.o
> -drm_client_lib-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fbdev_client.o
> +drm_client_lib-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fbdev_client.o \
> +						drm_fbdev_helper.o

[Severity: Low]
Since drm_fbdev_helper.o is now built into drm_client_lib, can this cause a
linker error for built-in memory helpers?

If CONFIG_DRM_FBDEV_EMULATION=y and a driver selects DRM_GEM_DMA_HELPER=y,
but CONFIG_DRM_CLIENT_SELECTION=m (selected only by modular drivers),
drm_client_lib.ko will be built as a module while drm_fbdev_dma.o becomes
built-in.

This would lead to undefined references to fbdev helper functions (e.g.,
drm_fb_helper_fini) during vmlinux linkage.

Do the memory helpers in drivers/gpu/drm/Kconfig (DRM_GEM_DMA_HELPER,
DRM_GEM_SHMEM_HELPER, DRM_TTM_HELPER) need to explicitly select
DRM_CLIENT_LIB when DRM_FBDEV_EMULATION is enabled to prevent this?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260924093036.82356-1-tzimmermann@suse.de?part=2