[PATCH v3 15/21] crypto/arm64: sha3 - Switch to 'ksimd' scoped guard API

Ard Biesheuvel
2025-10-08T15:47:03Z

Switch to the more abstract 'scoped_ksimd()' API, which will be modified
in a future patch to transparently allocate a kernel mode FP/SIMD state
buffer on the stack, so that kernel mode FP/SIMD code remains
preemptible in principe, but without the memory overhead that adds 528
bytes to the size of struct task_struct.

Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/arm64/crypto/sha3-ce-glue.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/crypto/sha3-ce-glue.c b/arch/arm64/crypto/sha3-ce-glue.c
index b4f1001046c9..22732760edd3 100644
--- a/arch/arm64/crypto/sha3-ce-glue.c
+++ b/arch/arm64/crypto/sha3-ce-glue.c
@@ -46,9 +46,8 @@ static int sha3_update(struct shash_desc *desc, const u8 *data,
do {
int rem;

- kernel_neon_begin();
- rem = sha3_ce_transform(sctx->st, data, blocks, ds);
- kernel_neon_end();
+ scoped_ksimd()
+ rem = sha3_ce_transform(sctx->st, data, blocks, ds);
data += (blocks - rem) * bs;
blocks = rem;
} while (blocks);
@@ -73,9 +72,8 @@ static int sha3_finup(struct shash_desc *desc, const u8 *src, unsigned int len,
memset(block + len, 0, bs - len);
block[bs - 1] |= 0x80;

- kernel_neon_begin();
- sha3_ce_transform(sctx->st, block, 1, ds);
- kernel_neon_end();
+ scoped_ksimd()
+ sha3_ce_transform(sctx->st, block, 1, ds);
memzero_explicit(block , sizeof(block));

for (i = 0; i < ds / 8; i++)
--
2.51.0.710.ga91ca5db03-goog