Patch "crypto: vmx - Increase priority of aes-cbc cipher" has been added to the 4.6-stable tree

This is a note to let you know that I've just added the patch titled

crypto: vmx - Increase priority of aes-cbc cipher

to the 4.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
crypto-vmx-increase-priority-of-aes-cbc-cipher.patch
and it can be found in the queue-4.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Anton Blanchard <[email protected]>
Date: Fri, 10 Jun 2016 16:47:03 +1000
Subject: crypto: vmx - Increase priority of aes-cbc cipher

From: Anton Blanchard <[email protected]>

commit 12d3f49e1ffbbf8cbbb60acae5a21103c5c841ac upstream.

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.

---
 drivers/crypto/vmx/aes_cbc.c |    2 +-
 drivers/crypto/vmx/aes_ctr.c |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

@@ -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,

@@ -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,

Patches currently in stable-queue which might be from [email protected] are

queue-4.6/crypto-vmx-increase-priority-of-aes-cbc-cipher.patch