From: Eric Biggers Date: Wed, 27 Aug 2025 15:11:28 +0000 (-0700) Subject: lib/crypto: blake2s: Always enable arch-optimized BLAKE2s code X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=56e48d4e138cb105a17e0f8c257f3bc41b1bd69d;p=users%2Fhch%2Fmisc.git lib/crypto: blake2s: Always enable arch-optimized BLAKE2s code When support for a crypto algorithm is enabled, the arch-optimized implementation of that algorithm should be enabled too. We've learned this the hard way many times over the years: people regularly forget to enable the arch-optimized implementations of the crypto algorithms, resulting in significant performance being left on the table. Currently, BLAKE2s support is always enabled ('obj-y'), since random.c uses it. Therefore, the arch-optimized BLAKE2s code, which exists for ARM and x86_64, should be always enabled too. Let's do that. Note that the effect on kernel image size is very small and should not be a concern. On ARM, enabling CRYPTO_BLAKE2S_ARM actually *shrinks* the kernel size by about 1200 bytes, since the ARM-optimized blake2s_compress() completely replaces the generic blake2s_compress(). On x86_64, enabling CRYPTO_BLAKE2S_X86 increases the kernel size by about 1400 bytes, as the generic blake2s_compress() is still included as a fallback; however, for context, that is only about a quarter the size of the generic blake2s_compress(). The x86_64 optimized BLAKE2s code uses much less icache at runtime than the generic code. Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250827151131.27733-10-ebiggers@kernel.org Signed-off-by: Eric Biggers --- diff --git a/lib/crypto/arm/Kconfig b/lib/crypto/arm/Kconfig index 740341aa35d2..a5607ad079c4 100644 --- a/lib/crypto/arm/Kconfig +++ b/lib/crypto/arm/Kconfig @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only config CRYPTO_BLAKE2S_ARM - bool "Hash functions: BLAKE2s" + def_bool y select CRYPTO_ARCH_HAVE_LIB_BLAKE2S help BLAKE2s cryptographic hash function (RFC 7693) diff --git a/lib/crypto/x86/Kconfig b/lib/crypto/x86/Kconfig index eb47da71aa6b..ffa718321369 100644 --- a/lib/crypto/x86/Kconfig +++ b/lib/crypto/x86/Kconfig @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only config CRYPTO_BLAKE2S_X86 - bool "Hash functions: BLAKE2s (SSSE3/AVX-512)" + def_bool y depends on 64BIT select CRYPTO_LIB_BLAKE2S_GENERIC select CRYPTO_ARCH_HAVE_LIB_BLAKE2S