stable inclusion
from stable-v5.10.124
commit d721986e967b3c5fef7495e3840362ba71d1968f
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6E7

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d721986e967b3c5fef7495e3840362ba71d1968f

--------------------------------

commit abfed87e upstream.

This is used by code that doesn't need CONFIG_CRYPTO, so move this into
lib/ with a Kconfig option so that it can be selected by whatever needs
it.

This fixes a linker error Zheng pointed out when
CRYPTO_MANAGER_DISABLE_TESTS!=y and CRYPTO=m:

  lib/crypto/curve25519-selftest.o: In function `curve25519_selftest':
  curve25519-selftest.c:(.init.text+0x60): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0xec): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0x114): undefined reference to `__crypto_memneq'
  curve25519-selftest.c:(.init.text+0x154): undefined reference to `__crypto_memneq'
Reported-by: NZheng Bin <zhengbin13@huawei.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: stable@vger.kernel.org
Fixes: aa127963 ("crypto: lib/curve25519 - re-add selftests")
Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>