On Mon, 28 Apr 2025 10:00:33 -0700
Eric Biggers [off-list ref] wrote:

From: Eric Biggers <redacted>

Instead of providing crypto_shash algorithms for the arch-optimized
SHA-256 code, instead implement the SHA-256 library.  This is much
simpler, it makes the SHA-256 library functions be arch-optimized, and
it fixes the longstanding issue where the arch-optimized SHA-256 was
disabled by default.  SHA-256 still remains available through
crypto_shash, but individual architectures no longer need to handle it.

I can get to the following error after this patch, now merged as commit
b9eac03edcf8 ("crypto: s390/sha256 - implement library instead of shash"):

error: the following would cause module name conflict:
  crypto/sha256.ko
  arch/s390/lib/crypto/sha256.ko

Base config file is generated from:

$ CONFIG=$(mktemp)
$ cat << EOF > $CONFIG
CONFIG_MODULES=y
CONFIG_CRYPTO=y
CONFIG_CRYPTO_SHA256=m
EOF

Base config applied to allnoconfig:

$ KCONFIG_ALLCONFIG=$CONFIG make ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- allnoconfig

Resulting in:

$ grep SHA256 .config
CONFIG_CRYPTO_SHA256=m
CONFIG_CRYPTO_LIB_SHA256=m
CONFIG_CRYPTO_ARCH_HAVE_LIB_SHA256=y
CONFIG_CRYPTO_LIB_SHA256_GENERIC=m
CONFIG_CRYPTO_SHA256_S390=m

Thanks,
Alex