openwrt/target/linux/generic/backport-5.4/080-wireguard-0048-crypto-x86-poly1305-emit-does-base-conversion-itself.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Fri, 17 Jan 2020 11:42:22 +0100
Subject: [PATCH] crypto: x86/poly1305 - emit does base conversion itself

commit f9e7fe32a792726186301423ff63a465d63386e1 upstream.

The emit code does optional base conversion itself in assembly, so we
don't need to do that here. Also, neither one of these functions uses
simd instructions, so checking for that doesn't make sense either.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 arch/x86/crypto/poly1305_glue.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

--- a/arch/x86/crypto/poly1305_glue.c
+++ b/arch/x86/crypto/poly1305_glue.c
@@ -123,13 +123,9 @@ static void poly1305_simd_blocks(void *c
 static void poly1305_simd_emit(void *ctx, u8 mac[POLY1305_DIGEST_SIZE],
 			       const u32 nonce[4])
 {
-	struct poly1305_arch_internal *state = ctx;
-
-	if (!IS_ENABLED(CONFIG_AS_AVX) || !static_branch_likely(&poly1305_use_avx) ||
-	    !state->is_base2_26 || !crypto_simd_usable()) {
-		convert_to_base2_64(ctx);
+	if (!IS_ENABLED(CONFIG_AS_AVX) || !static_branch_likely(&poly1305_use_avx))
 		poly1305_emit_x86_64(ctx, mac, nonce);
-	} else
+	else
 		poly1305_emit_avx(ctx, mac, nonce);
 }