FAILED: patch "[PATCH] crypto: qat - disable registration of algorithms" failed to apply to 4.9-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8893d27ffcaf6ec6267038a177cb87bcde4dd3de Mon Sep 17 00:00:00 2001
From: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Date: Fri, 4 Mar 2022 17:54:47 +0000
Subject: [PATCH] crypto: qat - disable registration of algorithms

The implementations of aead and skcipher in the QAT driver do not
support properly requests with the CRYPTO_TFM_REQ_MAY_BACKLOG flag set.
If the HW queue is full, the driver returns -EBUSY but does not enqueue
the request.
This can result in applications like dm-crypt waiting indefinitely for a
completion of a request that was never submitted to the hardware.

To avoid this problem, disable the registration of all crypto algorithms
in the QAT driver by setting the number of crypto instances to 0 at
configuration time.

Cc: stable@vger.kernel.org
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/qat/qat_4xxx/adf_drv.c b/drivers/crypto/qat/qat_4xxx/adf_drv.c
index a6c78b9c730b..fa4c350c1bf9 100644
--- a/drivers/crypto/qat/qat_4xxx/adf_drv.c
+++ b/drivers/crypto/qat/qat_4xxx/adf_drv.c
@@ -75,6 +75,13 @@ static int adf_crypto_dev_config(struct adf_accel_dev *accel_dev)
 	if (ret)
 		goto err;
 
+	/* Temporarily set the number of crypto instances to zero to avoid
+	 * registering the crypto algorithms.
+	 * This will be removed when the algorithms will support the
+	 * CRYPTO_TFM_REQ_MAY_BACKLOG flag
+	 */
+	instances = 0;
+
 	for (i = 0; i < instances; i++) {
 		val = i;
 		bank = i * 2;
diff --git a/drivers/crypto/qat/qat_common/qat_crypto.c b/drivers/crypto/qat/qat_common/qat_crypto.c
index 7234c4940fae..67c9588e89df 100644
--- a/drivers/crypto/qat/qat_common/qat_crypto.c
+++ b/drivers/crypto/qat/qat_common/qat_crypto.c
@@ -161,6 +161,13 @@ int qat_crypto_dev_config(struct adf_accel_dev *accel_dev)
 	if (ret)
 		goto err;
 
+	/* Temporarily set the number of crypto instances to zero to avoid
+	 * registering the crypto algorithms.
+	 * This will be removed when the algorithms will support the
+	 * CRYPTO_TFM_REQ_MAY_BACKLOG flag
+	 */
+	instances = 0;
+
 	for (i = 0; i < instances; i++) {
 		val = i;
 		snprintf(key, sizeof(key), ADF_CY "%d" ADF_RING_ASYM_BANK_NUM, i);