From a5fd24d19bbb586b1c6d235c2021e9bead22c9f5 Mon Sep 17 00:00:00 2001
From: Andy Polyakov <appro@openssl.org>
Date: Wed, 4 Nov 2015 23:57:06 +0100
Subject: [PATCH] aesni-sha256-x86_64.pl: fix crash on AMD Jaguar.
It was also found that stich performs suboptimally on AMD Jaguar, hence
execution is limited to XOP-capable and Intel processors.
Reviewed-by: Kurt Roeckx <kurt@openssl.org>
---
crypto/aes/asm/aesni-sha256-x86_64.pl | 7 ++-----
crypto/evp/e_aes_cbc_hmac_sha256.c | 11 +++++++++++
2 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/crypto/aes/asm/aesni-sha256-x86_64.pl b/crypto/aes/asm/aesni-sha256-x86_64.pl
index 74dad4440..8a8199445 100644
--- a/crypto/aes/asm/aesni-sha256-x86_64.pl
+++ b/crypto/aes/asm/aesni-sha256-x86_64.pl
@@ -140,11 +140,8 @@ $code.=<<___ if ($avx>1);
je ${func}_avx2
___
$code.=<<___;
- and \$`1<<30`,%eax # mask "Intel CPU" bit
- and \$`1<<28|1<<9`,%r10d # mask AVX+SSSE3 bits
- or %eax,%r10d
- cmp \$`1<<28|1<<9|1<<30`,%r10d
- je ${func}_avx
+ and \$`1<<28`,%r10d # check for AVX
+ jnz ${func}_avx
ud2
___
}
diff --git a/crypto/evp/e_aes_cbc_hmac_sha256.c b/crypto/evp/e_aes_cbc_hmac_sha256.c
index 411c77086..63f6e48d4 100644
--- a/crypto/evp/e_aes_cbc_hmac_sha256.c
+++ b/crypto/evp/e_aes_cbc_hmac_sha256.c
@@ -498,7 +498,18 @@ static int aesni_cbc_hmac_sha256_cipher(EVP_CIPHER_CTX *ctx,
iv = AES_BLOCK_SIZE;
# if defined(STITCHED_CALL)
+ /*
+ * Assembly stitch handles AVX-capable processors, but its
+ * performance is not optimal on AMD Jaguar, ~40% worse, for
+ * unknown reasons. Incidentally processor in question supports
+ * AVX, but not AMD-specific XOP extension, which can be used
+ * to identify it and avoid stitch invocation. So that after we
+ * establish that current CPU supports AVX, we even see if it's
+ * either even XOP-capable Bulldozer-based or GenuineIntel one.
+ */
if (OPENSSL_ia32cap_P[1] & (1 << (60 - 32)) && /* AVX? */
+ ((OPENSSL_ia32cap_P[1] & (1 << (43 - 32))) /* XOP? */
+ | (OPENSSL_ia32cap_P[0] & (1<<30))) && /* "Intel CPU"? */
plen > (sha_off + iv) &&
(blocks = (plen - (sha_off + iv)) / SHA256_CBLOCK)) {
SHA256_Update(&key->md, in + iv, sha_off);