lkml.org 
[lkml]   [2009]   [Aug]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/7] AlacrityVM guest drivers Reply-To:
On Thu, Aug 06, 2009 at 06:08:27AM -0600, Gregory Haskins wrote:
> Hi Michael,
>
> >>> On 8/6/2009 at 4:19 AM, in message <20090806081955.GA9752@redhat.com>,
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > On Mon, Aug 03, 2009 at 01:17:30PM -0400, Gregory Haskins wrote:
> >> (Applies to v2.6.31-rc5, proposed for linux-next after review is complete)
> >
> > These are guest drivers, right?
>
> Yep.
>
> > Merging the guest first means relying on
> > kernel interface from an out of tree driver, which well might change
> > before it goes in.
>
> ABI compatibility is already addressed/handled, so even if that is true its not a problem.

It is? With versioning? Presumably this:

+ params.devid = vdev->id;
+ params.version = version;
+
+ ret = vbus_pci_hypercall(VBUS_PCI_HC_DEVOPEN,
+ &params, sizeof(params));
+ if (ret < 0)
+ return ret;

Even assuming host even knows how to decode this structure (e.g. some
other host module doesn't use VBUS_PCI_HC_DEVOPEN), checks the version
and denies older guests, this might help guest not to crash, but guest
still won't work.

> > Would it make more sense to start merging with the host side of the project?
>
> Not necessarily, no. These are drivers for a "device", so its no
> different than merging any other driver really. This is especially
> true since the hypervisor is also already published and freely
> available today, so anyone can start using it.

The difference is clear to me: devices do not get to set kernel/userspace
interfaces. This "device" depends on a specific interface between
kernel and (guest) userspace.

--
MST


\
 
 \ /
  Last update: 2009-08-06 14:29    [W:0.191 / U:0.392 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site