Re: [PATCH] firmware_loader: make RUST_FW_LOADER_ABSTRACTIONS select FW_LOADER

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Nov 04, 2025 at 11:04:49PM +0900, Alexandre Courbot wrote:
> I have noticed that build will fail when doing the following:
> 
> - Start with the x86 defconfig,
> - Using nconfig, enable `CONFIG_RUST` and `CONFIG_DRM_NOVA`,
> - Start building.
> 
> The problem is that `CONFIG_RUST_FW_LOADER_ABSTRACTIONS` remains
> unselected, despite it being a dependency of `CONFIG_NOVA_CORE`. This
> seems to happen because `CONFIG_DRM_NOVA` selects `CONFIG_NOVA_CORE`.
> 
> Fix this by making `CONFIG_RUST_FW_LOADER_ABSTRACTIONS` select
> `CONFIG_FW_LOADER`, and by transition make all users of
> `CONFIG_RUST_FW_LOADER_ABSTRACTIONS` (so far, nova-core and net/phy)
> select it as well.
> 
> `CONFIG_FW_LOADER` is more often selected than depended on, so this
> seems to make sense generally speaking.
> 
> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
> ---
> I am not 100% percent confident that this is the proper fix, but the
> problem is undeniable. :) I guess the alternative would be to make nova-drm
> depend on nova-core instead of selecting it, but I suspect that the
> `select` behavior is correct in this case - after all, firmware loading
> does not make sense without any user.
> ---
>  drivers/base/firmware_loader/Kconfig | 2 +-
>  drivers/gpu/nova-core/Kconfig        | 2 +-
>  drivers/net/phy/Kconfig              | 2 +-
>  3 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig
> index 752b9a9bea03..15eff8a4b505 100644
> --- a/drivers/base/firmware_loader/Kconfig
> +++ b/drivers/base/firmware_loader/Kconfig
> @@ -38,7 +38,7 @@ config FW_LOADER_DEBUG
>  config RUST_FW_LOADER_ABSTRACTIONS
>  	bool "Rust Firmware Loader abstractions"
>  	depends on RUST
> -	depends on FW_LOADER=y
> +	select FW_LOADER

Please no, select should almost never be used, it causes hard-to-debug
issues.

As something is failing, perhaps another "depends" needs to be added
somewhere instead?


thanks,

greg k-h