Re: [PATCH v7 06/15] s390/vfio-ap: sysfs attribute to display the guest CRYCB

Cornelia Huck
2020-04-08T10:33:59Z

On Tue, 7 Apr 2020 15:20:06 -0400
Tony Krowiak <akrowiak@linux.ibm.com> wrote:

> The matrix of adapters and domains configured in a guest's CRYCB may
> differ from the matrix of adapters and domains assigned to the matrix mdev,
> so this patch introduces a sysfs attribute to display the CRYCB of a guest
> using the matrix mdev. For a matrix mdev denoted by $uuid, the crycb for a
> guest using the matrix mdev can be displayed as follows:
>
> cat /sys/devices/vfio_ap/matrix/$uuid/guest_matrix
>
> If a guest is not using the matrix mdev at the time the crycb is displayed,
> an error (ENODEV) will be returned.
>
> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
> ---
> drivers/s390/crypto/vfio_ap_ops.c | 58 +++++++++++++++++++++++++++++++
> 1 file changed, 58 insertions(+)

> +static DEVICE_ATTR_RO(guest_matrix);

Hm... should information like the guest configuration be readable by
everyone? Or should it be restricted a bit more?

> +
> static struct attribute *vfio_ap_mdev_attrs[] = {
> &dev_attr_assign_adapter.attr,
> &dev_attr_unassign_adapter.attr,
> @@ -1050,6 +1107,7 @@ static struct attribute *vfio_ap_mdev_attrs[] = {
> &dev_attr_unassign_control_domain.attr,
> &dev_attr_control_domains.attr,
> &dev_attr_matrix.attr,
> + &dev_attr_guest_matrix.attr,
> NULL,
> };
>