Re: [virtio] [PATCH] virtio-ccw: add adapter interrupt support

[Rusty Russell <rusty@au1.ibm.com>]

Cornelia Huck <cornelia.huck@de.ibm.com> writes:
> On Tue, 15 Oct 2013 14:13:58 +1030
> Rusty Russell <rusty@au1.ibm.com> wrote:
>
>> Cornelia Huck <cornelia.huck@de.ibm.com> writes:
>> > Specify a new channel command to set up two-stage indicators as needed
>> > for adapter interrupts and describe how adapter interrupts are used
>> > for notifications.
>> 
>> Since this presumably isn't in the current implementation, should there
>> be a legacy section talking about what happens if it's not supported?
>> Or is that implied and I missed it?
>
> As a device will reject any channel command it doesn't know, we should
> be fine. I'll add a legacy section though; a transitional driver should
> just fall back to classic indicators.

To make sure I understand correctly: a non-legacy device MUST support
this, right?  So a non-transitional driver can count on it?  (I guess
the command might fail for other reasons, so it's still nice for the
driver to fall back, but not compulsory).

Cheers,
Rusty.