linux-kernel - [PATCH v3 13/21] crypto/arm64: nhpoly1305

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251008154533.3089255-36-ardb+git@google.com>
Date: Wed,  8 Oct 2025 17:45:47 +0200
From: Ard Biesheuvel <ardb+git@...gle.com>
To: linux-arm-kernel@...ts.infradead.org
Cc: linux-kernel@...r.kernel.org, linux-crypto@...r.kernel.org, 
	herbert@...dor.apana.org.au, ebiggers@...nel.org, 
	Ard Biesheuvel <ardb@...nel.org>
Subject: [PATCH v3 13/21] crypto/arm64: nhpoly1305 - Switch to 'ksimd' scoped
 guard API

From: Ard Biesheuvel <ardb@...nel.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@...nel.org>
Signed-off-by: Ard Biesheuvel <ardb@...nel.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);
-- 
2.51.0.710.ga91ca5db03-goog