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.biesheu...@linaro.org>
---
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.biesheu...@linaro.org>
+ * Copyright (C) 2016 - 2017 Linaro, Ltd. <ard.biesheu...@linaro.org>
*
* 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);
--
2.7.4
