Re: [qemu-s390x] [PATCH 0/3] vfio-ccw: support hsch/csch (kernel part)

Halil Pasic
2018-11-24T21:07:57Z

On Thu, 22 Nov 2018 17:54:29 +0100
Cornelia Huck <cohuck@redhat.com> wrote:

> [This is the Linux kernel part, git tree is available at
> https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw.git
> vfio-ccw-caps
>
> The companion QEMU patches are available at
> https://github.com/cohuck/qemu vfio-ccw-caps]
>
> Currently, vfio-ccw only relays START SUBCHANNEL requests to the real
> device. This tends to work well for the most common 'good path'
> scenarios; however, as we emulate {HALT,CLEAR} SUBCHANNEL in QEMU,
> things like clearing pending requests at the device is currently not
> supported. This may be a problem for e.g. error recovery.
>
> This patch series introduces capabilities (similar to what vfio-pci
> uses) and exposes a new async region for handling hsch/csch.

I'm on vacation and could not do more than skim over it real quick. FWIW
it looks very promising. I intend to give it an in depth review once I'm
back (i.e. second half of next week).

Regards,
Halil