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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>,
	Giovanni Cabiddu <giovanni.cabiddu@intel.com>,
	Ahsan Atta <ahsan.atta@intel.com>
Subject: [PATCH] crypto: qat - add sysfs_added flag for rate limiting
Date: Tue, 21 Nov 2023 18:02:23 +0100
Message-ID: <20231121170252.8263-1-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 qat_rl sysfs attribute group is registered within the adf_dev_start()
function, alongside other driver components.
If any of the functions preceding the group registration fails,
the adf_dev_start() function returns, and the caller, to undo the
operation, invokes adf_dev_stop() followed by adf_dev_shutdown().
However, the current flow lacks information about whether the
registration of the qat_rl attribute group was successful or not.

In cases where this condition is encountered, an error similar to
the following might be reported:

    4xxx 0000:6b:00.0: Starting device qat_dev0
    4xxx 0000:6b:00.0: qat_dev0 started 9 acceleration engines
    4xxx 0000:6b:00.0: Failed to send init message
    4xxx 0000:6b:00.0: Failed to start device qat_dev0
    sysfs group 'qat_rl' not found for kobject '0000:6b:00.0'
    ...
    sysfs_remove_groups+0x2d/0x50
    adf_sysfs_rl_rm+0x44/0x70 [intel_qat]
    adf_rl_stop+0x2d/0xb0 [intel_qat]
    adf_dev_stop+0x33/0x1d0 [intel_qat]
    adf_dev_down+0xf1/0x150 [intel_qat]
    ...
    4xxx 0000:6b:00.0: qat_dev0 stopped 9 acceleration engines
    4xxx 0000:6b:00.0: Resetting device qat_dev0

To prevent attempting to remove attributes from a group that has not
been added yet, a flag named 'sysfs_added' is introduced. This flag
is set to true upon the successful registration of the attribute group.

Fixes: d9fb8408376e ("crypto: qat - add rate limiting feature to qat_4xxx")
Signed-off-by: Damian Muszynski <damian.muszynski@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Ahsan Atta <ahsan.atta@intel.com>
---
 drivers/crypto/intel/qat/qat_common/adf_rl.h       | 1 +
 drivers/crypto/intel/qat/qat_common/adf_sysfs_rl.c | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/drivers/crypto/intel/qat/qat_common/adf_rl.h b/drivers/crypto/intel/qat/qat_common/adf_rl.h
index eb5a330f8543..269c6656fb90 100644
--- a/drivers/crypto/intel/qat/qat_common/adf_rl.h
+++ b/drivers/crypto/intel/qat/qat_common/adf_rl.h
@@ -79,6 +79,7 @@ struct adf_rl_interface_data {
 	struct adf_rl_sla_input_data input;
 	enum adf_base_services cap_rem_srv;
 	struct rw_semaphore lock;
+	bool sysfs_added;
 };
 
 struct adf_rl_hw_data {
diff --git a/drivers/crypto/intel/qat/qat_common/adf_sysfs_rl.c b/drivers/crypto/intel/qat/qat_common/adf_sysfs_rl.c
index abf9c52474ec..bedb514d4e30 100644
--- a/drivers/crypto/intel/qat/qat_common/adf_sysfs_rl.c
+++ b/drivers/crypto/intel/qat/qat_common/adf_sysfs_rl.c
@@ -441,11 +441,19 @@ int adf_sysfs_rl_add(struct adf_accel_dev *accel_dev)
 
 	data->cap_rem_srv = ADF_SVC_NONE;
 	data->input.srv = ADF_SVC_NONE;
+	data->sysfs_added = true;
 
 	return ret;
 }
 
 void adf_sysfs_rl_rm(struct adf_accel_dev *accel_dev)
 {
+	struct adf_rl_interface_data *data;
+
+	data = &GET_RL_STRUCT(accel_dev);
+	if (!data->sysfs_added)
+		return;
+
 	device_remove_group(&GET_DEV(accel_dev), &qat_rl_group);
+	data->sysfs_added = false;
 }

base-commit: f36285cc1e99472bb4c6741981594a5934ad4c4e
-- 
2.41.0