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From: Damian Muszynski <damian.muszynski@intel.com>
To: herbert@gondor.apana.org.au
Cc: linux-crypto@vger.kernel.org,
	qat-linux@intel.com,
	Damian Muszynski <damian.muszynski@intel.com>,
	stable@vger.kernel.org,
	Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Subject: [PATCH] crypto: qat - change SLAs cleanup flow at shutdown
Date: Fri,  9 Feb 2024 13:42:07 +0100
Message-ID: <20240209124237.44530-1-damian.muszynski@intel.com>
Precedence: bulk
MIME-Version: 1.0
Organization: Intel Technology Poland sp. z o.o. - ul. Slowackiego 173, 80-298 Gdansk - KRS 101882 - NIP 957-07-52-316
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The implementation of the Rate Limiting (RL) feature includes the cleanup
of all SLAs during device shutdown. For each SLA, the firmware is notified
of the removal through an admin message, the data structures that take
into account the budgets are updated and the memory is freed.
However, this explicit cleanup is not necessary as (1) the device is
reset, and the firmware state is lost and (2) all RL data structures
are freed anyway.

In addition, if the device is unresponsive, for example after a PCI
AER error is detected, the admin interface might not be available.
This might slow down the shutdown sequence and cause a timeout in
the recovery flows which in turn makes the driver believe that the
device is not recoverable.

Fix by replacing the explicit SLAs removal with just a free of the
SLA data structures.

Fixes: d9fb8408376e ("crypto: qat - add rate limiting feature to qat_4xxx")
Cc: <stable@vger.kernel.org>
Signed-off-by: Damian Muszynski <damian.muszynski@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
---
 drivers/crypto/intel/qat/qat_common/adf_rl.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/intel/qat/qat_common/adf_rl.c b/drivers/crypto/intel/qat/qat_common/adf_rl.c
index de1b214dba1f..d4f2db3c53d8 100644
--- a/drivers/crypto/intel/qat/qat_common/adf_rl.c
+++ b/drivers/crypto/intel/qat/qat_common/adf_rl.c
@@ -788,6 +788,24 @@ static void clear_sla(struct adf_rl *rl_data, struct rl_sla *sla)
 	sla_type_arr[node_id] = NULL;
 }
 
+static void free_all_sla(struct adf_accel_dev *accel_dev)
+{
+	struct adf_rl *rl_data = accel_dev->rate_limiting;
+	int sla_id;
+
+	mutex_lock(&rl_data->rl_lock);
+
+	for (sla_id = 0; sla_id < RL_NODES_CNT_MAX; sla_id++) {
+		if (!rl_data->sla[sla_id])
+			continue;
+
+		kfree(rl_data->sla[sla_id]);
+		rl_data->sla[sla_id] = NULL;
+	}
+
+	mutex_unlock(&rl_data->rl_lock);
+}
+
 /**
  * add_update_sla() - handles the creation and the update of an SLA
  * @accel_dev: pointer to acceleration device structure
@@ -1155,7 +1173,7 @@ void adf_rl_stop(struct adf_accel_dev *accel_dev)
 		return;
 
 	adf_sysfs_rl_rm(accel_dev);
-	adf_rl_remove_sla_all(accel_dev, true);
+	free_all_sla(accel_dev);
 }
 
 void adf_rl_exit(struct adf_accel_dev *accel_dev)

base-commit: 84c2f23ad68a847e36dc9cae44f21c5e321a321c
-- 
2.43.0