Re: [PATCH v3] docs/s390x: document vfio-ccw

[Thomas Huth]

On 18/05/2020 09.55, Cornelia Huck wrote:
> Add a basic example for passing a dasd via vfio-ccw.
> 
> Signed-off-by: Cornelia Huck <address@hidden>
> ---
> 
> v2->v3: moved uuid generation (Thomas)
> 
> ---
>  docs/system/s390x/vfio-ccw.rst | 77 ++++++++++++++++++++++++++++++++++
>  docs/system/target-s390x.rst   |  1 +
>  2 files changed, 78 insertions(+)
>  create mode 100644 docs/system/s390x/vfio-ccw.rst
> 
> diff --git a/docs/system/s390x/vfio-ccw.rst b/docs/system/s390x/vfio-ccw.rst
> new file mode 100644
> index 000000000000..fff23d9afff7
> --- /dev/null
> +++ b/docs/system/s390x/vfio-ccw.rst
> @@ -0,0 +1,77 @@
> +Subchannel passthrough via vfio-ccw
> +===================================
> +
> +vfio-ccw (based upon the mediated vfio device infrastructure) allows to
> +make certain I/O subchannels and their devices available to a guest. The
> +host will not interact with those subchannels/devices any more.
> +
> +Note that while vfio-ccw should work with most non-QDIO devices, only ECKD
> +DASDs have really been tested.
> +
> +Example configuration
> +---------------------
> +
> +Step 1: configure the host device
> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> +
> +As every mdev is identified by a uuid, the first step is to obtain one::
> +
> +  [root@host ~]# uuidgen
> +  7e270a25-e163-4922-af60-757fc8ed48c6
> +
> +Note: it is recommended to use the ``mdevctl`` tool for actually configuring
> +the host device.
> +
> +To define the same device as configured below to be started
> +automatically, use
> +
> +::
> +
> +   [root@host ~]# driverctl -b css set-override 0.0.0313 vfio_ccw
> +   [root@host ~]# mdevctl define -u 7e270a25-e163-4922-af60-757fc8ed48c6\

Maybe add a space before the backslash?

> +                  -p 0.0.0313 -t vfio-ccw_io -a
> +
> +If using ``mdevctl``  is not possible or wanted, follow the manual procedure
> +below.

Nit: Doubled whitespaces after mdevctl. With that fixed:
Reviewed-by: Thomas Huth <address@hidden>