[PATCH v2 07/20] crypto/arm64: sm4-ce-ccm - Avoid pointless yield of the NEON unit
From: Ard Biesheuvel <hidden>
Date: 2025-10-01 21:04:00
Also in:
linux-crypto, lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
From: Ard Biesheuvel <ardb@kernel.org> Kernel mode NEON sections are now preemptible on arm64, and so there is no need to yield it when calling APIs that may sleep. Also, move the calls to kernel_neon_end() to the same scope as kernel_neon_begin(). This is needed for a subsequent change where a stack buffer is allocated transparently and passed to kernel_neon_begin(). Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- arch/arm64/crypto/sm4-ce-ccm-glue.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/arch/arm64/crypto/sm4-ce-ccm-glue.c b/arch/arm64/crypto/sm4-ce-ccm-glue.c
index e9cc1c1364ec..f9771ab2a05f 100644
--- a/arch/arm64/crypto/sm4-ce-ccm-glue.c
+++ b/arch/arm64/crypto/sm4-ce-ccm-glue.c@@ -179,11 +179,7 @@ static int ccm_crypt(struct aead_request *req, struct skcipher_walk *walk, walk->src.virt.addr, walk->iv, walk->nbytes - tail, mac); - kernel_neon_end(); - err = skcipher_walk_done(walk, tail); - - kernel_neon_begin(); } if (walk->nbytes) {
@@ -193,15 +189,13 @@ static int ccm_crypt(struct aead_request *req, struct skcipher_walk *walk, sm4_ce_ccm_final(rkey_enc, ctr0, mac); - kernel_neon_end(); - err = skcipher_walk_done(walk, 0); } else { sm4_ce_ccm_final(rkey_enc, ctr0, mac); - - kernel_neon_end(); } + kernel_neon_end(); + return err; }
--
2.51.0.618.g983fd99d29-goog