Re: [PATCH V4 4/5] misc: mlx5ctl: Add command rpc ioctl

[Saeed Mahameed <saeed@kernel.org>]

On 29 Feb 12:49, Vegard Nossum wrote:
>
>On 07/02/2024 08:24, Saeed Mahameed wrote:
>>@@ -328,6 +420,11 @@ static int mlx5ctl_probe(struct auxiliary_device *adev,
>>  		goto abort;
>>  	}
>>+	err = sysfs_create_link_nowarn(&mcdev->miscdev.this_device->kobj,
>>+				       &mdev->device->kobj, "mdev");
>>+	if (err)
>>+		mlx5ctl_dbg(mcdev, "mlx5ctl: failed to create sysfs link err %d\n", err);
>>+
>
>Should this propagate the error to the caller?
>

this link is informational only and not necessary for the driver function,
it meant to help user-space apps to associate mlx5ctl driver with it parent 
mlx5_core device.

>What happens if/when mlx5ctl_remove()/sysfs_remove_link() gets called
>later for this kobj?
>

sysfs_remove_link() will eventually call kernfs_remove_by_name_ns()
and it will return -ENOENT; if not found, and it will be silently dropped.