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

Arnd Bergmann
2023-10-23T11:04:01Z

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
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(-)

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