[PATCH v4 13/21] crypto/arm64: nhpoly1305 - Switch to 'ksimd' scoped guard API

Ard Biesheuvel ardb+git at google.com
Fri Oct 31 03:39:12 PDT 2025


From: Ard Biesheuvel <ardb at kernel.org>

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 at kernel.org>
Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/arm64/crypto/nhpoly1305-neon-glue.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/crypto/nhpoly1305-neon-glue.c b/arch/arm64/crypto/nhpoly1305-neon-glue.c
index e4a0b463f080..013de6ac569a 100644
--- a/arch/arm64/crypto/nhpoly1305-neon-glue.c
+++ b/arch/arm64/crypto/nhpoly1305-neon-glue.c
@@ -25,9 +25,8 @@ static int nhpoly1305_neon_update(struct shash_desc *desc,
 	do {
 		unsigned int n = min_t(unsigned int, srclen, SZ_4K);
 
-		kernel_neon_begin();
-		crypto_nhpoly1305_update_helper(desc, src, n, nh_neon);
-		kernel_neon_end();
+		scoped_ksimd()
+			crypto_nhpoly1305_update_helper(desc, src, n, nh_neon);
 		src += n;
 		srclen -= n;
 	} while (srclen);
-- 
2.51.1.930.gacf6e81ea2-goog




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