To accommodate systems that disallow the use of kernel mode NEON in some circumstances, take the return value of may_use_simd into account when deciding whether to invoke the C fallback routine. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> --- arch/arm64/crypto/chacha20-neon-glue.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm64/crypto/chacha20-neon-glue.c b/arch/arm64/crypto/chacha20-neon-glue.c index a7cd575ea223..cbdb75d15cd0 100644 --- a/arch/arm64/crypto/chacha20-neon-glue.c +++ b/arch/arm64/crypto/chacha20-neon-glue.c @@ -1,7 +1,7 @@ /* * ChaCha20 256-bit cipher algorithm, RFC7539, arm64 NEON functions * - * Copyright (C) 2016 Linaro, Ltd. <ard.biesheuvel@xxxxxxxxxx> + * Copyright (C) 2016 - 2017 Linaro, Ltd. <ard.biesheuvel@xxxxxxxxxx> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -26,6 +26,7 @@ #include <asm/hwcap.h> #include <asm/neon.h> +#include <asm/simd.h> asmlinkage void chacha20_block_xor_neon(u32 *state, u8 *dst, const u8 *src); asmlinkage void chacha20_4block_xor_neon(u32 *state, u8 *dst, const u8 *src); @@ -64,7 +65,7 @@ static int chacha20_neon(struct skcipher_request *req) u32 state[16]; int err; - if (req->cryptlen <= CHACHA20_BLOCK_SIZE) + if (!may_use_simd() || req->cryptlen <= CHACHA20_BLOCK_SIZE) return crypto_chacha20_crypt(req); err = skcipher_walk_virt(&walk, req, true); -- 2.9.3