Subject: [PATCH 0/2] Early printk support for virtio console devices.

From: [email-masked] (Rusty Russell)
Date: Wed, 01 May 2013 11:37:36 +0930

Alexander Graf <[email-masked]> writes:
> There are not device specific registers in
> virtio-console. Virtio-console lives behind a virtio bus which doesn't
> know what these registers are.

You're not going to make coherent arguments without reading that actual
patch we're discussing.  And you're going to just waste everyone else's
time.

> Even if you shove it into config space,

Which is what the patch does...

> it'd be broken because config access happens without intercepts on
> some platforms.

But people keep assuming it, which is one reason virtio_ccw switched
from passive lguest-style config to active.  Only lguest and the old kvm
virtio use it, and lguest can change.

An emergency output is a reasonable idea, and this is a reasonable
implementation.  The question is practical: will it be used?  Because we
don't implement reasonable ideas which aren't going to be used.

Cheers,
Rusty.