nvme-hwmon: consistently ignore errors from nvme_hwmon_init

[ Upstream commit 6b8cf94 ]

An NVMe controller works perfectly fine even when the hwmon
initialization fails.  Stop returning errors that do not come from a
controller reset from nvme_hwmon_init to handle this case consistently.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Stable-dep-of: c94b7f9 ("nvme-hwmon: kmalloc the NVME SMART log buffer")
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/nvme/host/core.c

@@ -3256,8 +3256,12 @@ int nvme_init_ctrl_finish(struct nvme_ctrl *ctrl)
 		return ret;
 
 	if (!ctrl->identified && !nvme_discovery_ctrl(ctrl)) {
+		/*
+		 * Do not return errors unless we are in a controller reset,
+		 * the controller works perfectly fine without hwmon.
+		 */
 		ret = nvme_hwmon_init(ctrl);
-		if (ret < 0)
+		if (ret == -EINTR)
 			return ret;
 	}
 

drivers/nvme/host/hwmon.c

@@ -230,28 +230,31 @@ int nvme_hwmon_init(struct nvme_ctrl *ctrl)
 
 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (!data)
-		return 0;
+		return -ENOMEM;
 
 	data->ctrl = ctrl;
 	mutex_init(&data->read_lock);
 
 	err = nvme_hwmon_get_smart_log(data);
 	if (err) {
 		dev_warn(dev, "Failed to read smart log (error %d)\n", err);
-		kfree(data);
-		return err;
+		goto err_free_data;
 	}
 
 	hwmon = hwmon_device_register_with_info(dev, "nvme",
 						data, &nvme_hwmon_chip_info,
 						NULL);
 	if (IS_ERR(hwmon)) {
 		dev_warn(dev, "Failed to instantiate hwmon device\n");
-		kfree(data);
-		return PTR_ERR(hwmon);
+		err = PTR_ERR(hwmon);
+		goto err_free_data;
 	}
 	ctrl->hwmon_device = hwmon;
 	return 0;
+
+err_free_data:
+	kfree(data);
+	return err;
 }
 
 void nvme_hwmon_exit(struct nvme_ctrl *ctrl)