Re: [PATCH RFC 0/1] mdevctl: further config for vfio-ap

Matthew Rosato
2019-06-06T16:46:03Z

On 6/6/19 10:44 AM, Cornelia Huck wrote:
> This patch adds a very rough implementation of additional config data
> for mdev devices. The idea is to make it possible to specify some
> type-specific key=value pairs in the config file for an mdev device.
> If a device is started automatically, the device is stopped and restarted
> after applying the config.
>
> The code has still some problems, like not doing a lot of error handling
> and being ugly in general; but most importantly, I can't really test it,
> as I don't have the needed hardware. Feedback welcome; would be good to
> know if the direction is sensible in general.

Hi Connie,

This is very similar to what I was looking to do in zdev (config via
key=value pairs), so I like your general approach.

I pulled your code and took it for a spin on an LPAR with access to
crypto cards:

# mdevctl create-mdev `uuidgen` matrix vfio_ap-passthrough
# mdevctl set-additional-config <uuid> ap_adapters=0x4,0x5
# mdevctl set-additional-config <uuid> ap_domains=0x36
# mdevctl set-additional-config <uuid> ap_control_domains=0x37

Assuming all valid inputs, this successfully creates the appropriate
mdev and what looks to be a valid mdevctl.d entry. A subsequent reboot
successfully brings the same vfio_ap-passthrough device up again.

Matt

>
> Also available at
>
> https://github.com/cohuck/mdevctl conf-data
>
> Cornelia Huck (1):
> allow to specify additional config data
>
> mdevctl.libexec | 25 ++++++++++++++++++++++
> mdevctl.sbin | 56 ++++++++++++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 80 insertions(+), 1 deletion(-)
>