Re: [virtio] [PATCH v3 1/1] virtio-ccw: introduce revisions

Cornelia Huck <> writes:
> On Tue, 05 Nov 2013 16:59:19 +1030
> Rusty Russell <> wrote:
>
>> Cornelia Huck <> writes:
>> > Provide a new ccw that allows devices and drivers to operate on selected
>> > revision levels.
>> >
>> > VIRTIO-42
>> >
>> > Signed-off-by: Cornelia Huck <>
>> >
>> > ---
>> >
>> > Changes v2 -> v3:
>> >  - Reset will not clear the revision; instead, the revision is cleared
>> >    when the subchannel is disabled
>> 
>> Does this work properly across kexec scenarios?
>
> Kexec on s390 will do a diagnose (hypercall) that triggers (among other
> things) a channel subsystem reset, which in turn includes disabling all
> subchannels. This means the kexeced guest will be presented with an
> unset revision.

Great, thanks.

Cheers,
Rusty.