[PATCH 2/2] kexec: select CRYPTO from KEXEC_FILE instead of depending on it

[Baoquan He]

On 10/23/23 at 01:01pm, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd at arndb.de>
> 
> All other users of crypto code use 'select' instead of 'depends on',
> so do the same thing with KEXEC_FILE for consistency.
> 
> In practice this makes very little difference as kernels with kexec
> support are very likely to also include some other feature that already
> selects both crypto and crypto_sha256, but being consistent here helps
> for usability as well as to avoid potential circular dependencies.
> 
> This reverts the dependency back to what it was originally before commit
> 74ca317c26a3f ("kexec: create a new config option CONFIG_KEXEC_FILE for
> new syscall"), which changed changed it with the comment "This should
                       ~~~~~~~~~~~~~~ typo
> be safer as "select" is not recursive", but that appears to have been
> done in error, as "select" is indeed recursive, and there are no other
> dependencies that prevent CRYPTO_SHA256 from being selected here.
> 
> Fixes: 74ca317c26a3f ("kexec: create a new config option CONFIG_KEXEC_FILE for new syscall")
> Cc: Herbert Xu <herbert at gondor.apana.org.au>
> Cc: "David S. Miller" <davem at davemloft.net>
> Cc: linux-crypto at vger.kernel.org
> Signed-off-by: Arnd Bergmann <arnd at arndb.de>
> ---
>  kernel/Kconfig.kexec | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

LGTM,

Acked-by: Baoquan He <bhe at redhat.com>

> 
> diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec
> index bfc636d64ff2b..51f719af10e79 100644
> --- a/kernel/Kconfig.kexec
> +++ b/kernel/Kconfig.kexec
> @@ -36,7 +36,8 @@ config KEXEC
>  config KEXEC_FILE
>  	bool "Enable kexec file based system call"
>  	depends on ARCH_SUPPORTS_KEXEC_FILE
> -	depends on CRYPTO_SHA256=y || !ARCH_SUPPORTS_KEXEC_PURGATORY
> +	select CRYPTO
> +	select CRYPTO_SHA256
>  	select KEXEC_CORE
>  	help
>  	  This is new version of kexec system call. This system call is
> -- 
> 2.39.2
>