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

From: Baoquan He <bhe@redhat.com>
To: Arnd Bergmann <arnd@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	"David S . Miller" <davem@davemloft.net>,
	linux-crypto@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
	Nicholas Piggin <npiggin@gmail.com>,
	Christophe Leroy <christophe.leroy@csgroup.eu>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Heiko Carstens <hca@linux.ibm.com>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Alexander Gordeev <agordeev@linux.ibm.com>,
	Christian Borntraeger <borntraeger@linux.ibm.com>,
	Sven Schnelle <svens@linux.ibm.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
	Eric DeVolder <eric.devolder@oracle.com>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	Ard Biesheuvel <ardb@kernel.org>,
	linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
	linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org,
	Hari Bathini <hbathini@linux.ibm.com>,
	Costa Shulyupin <costa.shul@redhat.com>
Subject: Re: [PATCH 2/2] kexec: select CRYPTO from KEXEC_FILE instead of depending on it
Date: Tue, 24 Oct 2023 11:55:26 +0800	[thread overview]
Message-ID: <ZTdALtO2rN4FaneC@MiWiFi-R3L-srv> (raw)
In-Reply-To: <20231023110308.1202042-2-arnd@kernel.org>

On 10/23/23 at 01:01pm, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@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@gondor.apana.org.au>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: linux-crypto@vger.kernel.org
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  kernel/Kconfig.kexec | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

LGTM,

Acked-by: Baoquan He <bhe@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
>