[added to the 4.1 stable tree] crypto: vmx - Increase priority of aes-cbc cipher

[Sasha Levin <sasha.levin@xxxxxxxxxx>]

From: Anton Blanchard <anton@xxxxxxxxx>

This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.

===============

[ Upstream commit 12d3f49e1ffbbf8cbbb60acae5a21103c5c841ac ]

All of the VMX AES ciphers (AES, AES-CBC and AES-CTR) are set at
priority 1000. Unfortunately this means we never use AES-CBC and
AES-CTR, because the base AES-CBC cipher that is implemented on
top of AES inherits its priority.

To fix this, AES-CBC and AES-CTR have to be a higher priority. Set
them to 2000.

Testing on a POWER8 with:

cryptsetup benchmark --cipher aes --key-size 256

Shows decryption speed increase from 402.4 MB/s to 3069.2 MB/s,
over 7x faster. Thanks to Mike Strosaker for helping me debug
this issue.

Fixes: 8c755ace357c ("crypto: vmx - Adding CBC routines for VMX module")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Anton Blanchard <anton@xxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
---
 drivers/crypto/vmx/aes_cbc.c | 2 +-
 drivers/crypto/vmx/aes_ctr.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/vmx/aes_cbc.c b/drivers/crypto/vmx/aes_cbc.c
index c8e7f65..f508cea 100644
--- a/drivers/crypto/vmx/aes_cbc.c
+++ b/drivers/crypto/vmx/aes_cbc.c
@@ -167,7 +167,7 @@ struct crypto_alg p8_aes_cbc_alg = {
     .cra_name = "cbc(aes)",
     .cra_driver_name = "p8_aes_cbc",
     .cra_module = THIS_MODULE,
-    .cra_priority = 1000,
+    .cra_priority = 2000,
     .cra_type = &crypto_blkcipher_type,
     .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | CRYPTO_ALG_NEED_FALLBACK,
     .cra_alignmask = 0,
diff --git a/drivers/crypto/vmx/aes_ctr.c b/drivers/crypto/vmx/aes_ctr.c
index 266e708..d8fa3b4 100644
--- a/drivers/crypto/vmx/aes_ctr.c
+++ b/drivers/crypto/vmx/aes_ctr.c
@@ -151,7 +151,7 @@ struct crypto_alg p8_aes_ctr_alg = {
     .cra_name = "ctr(aes)",
     .cra_driver_name = "p8_aes_ctr",
     .cra_module = THIS_MODULE,
-    .cra_priority = 1000,
+    .cra_priority = 2000,
     .cra_type = &crypto_blkcipher_type,
     .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | CRYPTO_ALG_NEED_FALLBACK,
     .cra_alignmask = 0,
-- 
2.5.0

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