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Date: Tue, 3 Apr 2007 12:51:39 +0200
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Andi Kleen <ak@suse.de>
Cc: Christian Borntraeger <borntrae@de.ibm.com>,
       virtualization@lists.linux-foundation.org,
       Jeremy Fitzhardinge <jeremy@goop.org>, "H. Peter Anvin" <hpa@zytor.com>,
       Virtualization Mailing List <virtualization@lists.osdl.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       mathiasen@gmail.com
Subject: Re: A set of "standard" virtual devices?
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On Tue, 3 Apr 2007 11:26:52 +0200,
Andi Kleen <ak@suse.de> wrote:

> > 
> > On s390, it would be more than strangeness. There's no implementation
> > of PCI at all, someone would have to cook it up - and it wouldn't have
> > any use beyond those special devices. Since there isn't any bus type
> > that is available on *all* architectures, a generic "virtual" bus with
> > very simple probing seems much saner...
> 
> You just have to change all the distribution installers then. 
> Ok I suppose on s390 that's not that big issue because there are not
> that many for s390. But for x86 there exist quite a lot. I suppose
> it's easier to change it in the kernel.

Huh? I don't follow you here. Why should this be easier for s390 vs.
x86? (And since there seems to be a trend to use HAL as a device
discovery tool recently: A new bus type is easy enough to add there.)

And I really think we should have a clean design in the kernel instead
of trying to wedge virtual devices into a known system. Exposing
virtual devices (which may be handled totally differently) as PCI
devices just seems hackish to me.