From 11d6bc70fff310cf0c4bbfa740144b0e350cd706 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Tue, 31 Mar 2026 17:05:40 -0700 Subject: lib/crypto: arm64/aes: Remove obsolete chunking logic Since commit aefbab8e77eb ("arm64: fpsimd: Preserve/restore kernel mode NEON at context switch"), kernel-mode NEON sections have been preemptible on arm64. And since commit 7dadeaa6e851 ("sched: Further restrict the preemption modes"), voluntary preemption is no longer supported on arm64 either. Therefore, there's no longer any need to limit the length of kernel-mode NEON sections on arm64. Simplify the AES-CBC-MAC code accordingly. Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260401000548.133151-2-ebiggers@kernel.org Signed-off-by: Eric Biggers --- lib/crypto/arm64/aes-modes.S | 8 +++----- lib/crypto/arm64/aes.h | 35 +++++++++++++---------------------- 2 files changed, 16 insertions(+), 27 deletions(-) (limited to 'lib') diff --git a/lib/crypto/arm64/aes-modes.S b/lib/crypto/arm64/aes-modes.S index fc89cd02b642..10e537317eaf 100644 --- a/lib/crypto/arm64/aes-modes.S +++ b/lib/crypto/arm64/aes-modes.S @@ -817,9 +817,9 @@ AES_FUNC_END(aes_xts_decrypt) #if IS_ENABLED(CONFIG_CRYPTO_LIB_AES_CBC_MACS) /* - * size_t aes_mac_update(u8 const in[], u32 const rk[], int rounds, - * size_t blocks, u8 dg[], int enc_before, - * int enc_after); + * void aes_mac_update(u8 const in[], u32 const rk[], int rounds, + * size_t blocks, u8 dg[], int enc_before, + * int enc_after); */ AES_FUNC_START(aes_mac_update) ld1 {v0.16b}, [x4] /* get dg */ @@ -844,7 +844,6 @@ AES_FUNC_START(aes_mac_update) cbz w5, .Lmacout encrypt_block v0, w2, x1, x7, w8 st1 {v0.16b}, [x4] /* return dg */ - cond_yield .Lmacout, x7, x8 b .Lmacloop4x .Lmac1x: add x3, x3, #4 @@ -863,7 +862,6 @@ AES_FUNC_START(aes_mac_update) .Lmacout: st1 {v0.16b}, [x4] /* return dg */ - mov x0, x3 ret AES_FUNC_END(aes_mac_update) #endif /* CONFIG_CRYPTO_LIB_AES_CBC_MACS */ diff --git a/lib/crypto/arm64/aes.h b/lib/crypto/arm64/aes.h index 135d3324a30a..9e9e45a6f787 100644 --- a/lib/crypto/arm64/aes.h +++ b/lib/crypto/arm64/aes.h @@ -29,9 +29,9 @@ asmlinkage void __aes_ce_decrypt(const u32 inv_rk[], u8 out[AES_BLOCK_SIZE], asmlinkage u32 __aes_ce_sub(u32 l); asmlinkage void __aes_ce_invert(struct aes_block *out, const struct aes_block *in); -asmlinkage size_t neon_aes_mac_update(u8 const in[], u32 const rk[], int rounds, - size_t blocks, u8 dg[], int enc_before, - int enc_after); +asmlinkage void neon_aes_mac_update(u8 const in[], u32 const rk[], int rounds, + size_t blocks, u8 dg[], int enc_before, + int enc_after); /* * Expand an AES key using the crypto extensions if supported and usable or @@ -192,25 +192,16 @@ static bool aes_cbcmac_blocks_arch(u8 h[AES_BLOCK_SIZE], bool enc_after) { if (static_branch_likely(&have_neon) && likely(may_use_simd())) { - do { - size_t rem; - - scoped_ksimd() { - if (static_branch_likely(&have_aes)) - rem = ce_aes_mac_update( - data, key->k.rndkeys, - key->nrounds, nblocks, h, - enc_before, enc_after); - else - rem = neon_aes_mac_update( - data, key->k.rndkeys, - key->nrounds, nblocks, h, - enc_before, enc_after); - } - data += (nblocks - rem) * AES_BLOCK_SIZE; - nblocks = rem; - enc_before = false; - } while (nblocks); + scoped_ksimd() { + if (static_branch_likely(&have_aes)) + ce_aes_mac_update(data, key->k.rndkeys, + key->nrounds, nblocks, h, + enc_before, enc_after); + else + neon_aes_mac_update(data, key->k.rndkeys, + key->nrounds, nblocks, h, + enc_before, enc_after); + } return true; } return false; -- cgit v1.2.3