[SRU Xenial, Yakkety][PATCH 3/3] UBUNTU: SAUCE: crypto: vmx - Increase priority of aes-cbc cipher

[Kamal Mostafa]

From: Anton Blanchard <anton at samba.org>

BugLink: http://bugs.launchpad.net/bugs/1592481

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 at vger.kernel.org
Signed-off-by: Anton Blanchard <anton at samba.org>
Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
(cherry picked from commit 12d3f49e1ffbbf8cbbb60acae5a21103c5c841ac git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6)
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
Acked-by: Brad Figg <brad.figg at canonical.com>
---
 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 0b8fe2e..f3801b9 100644
--- a/drivers/crypto/vmx/aes_cbc.c
+++ b/drivers/crypto/vmx/aes_cbc.c
@@ -182,7 +182,7 @@ 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 ee1306c..404a1b6 100644
--- a/drivers/crypto/vmx/aes_ctr.c
+++ b/drivers/crypto/vmx/aes_ctr.c
@@ -166,7 +166,7 @@ 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,
-- 
2.7.4