Re: [QEMU][PATCHv2 1/8] xen: when unplugging emulated devices skip virtio devices

[Vikram Garhwal]

On Thu, Oct 26, 2023 at 04:45:21PM +0100, David Woodhouse wrote:
> On Wed, 2023-10-25 at 18:23 -0700, Stefano Stabellini wrote:
> > On Thu, 26 Oct 2023, David Woodhouse wrote:
> > > On Wed, 2023-10-25 at 14:24 -0700, Vikram Garhwal wrote:
> > > > From: Juergen Gross <jgross@suse.com>
> > > > 
> > > > Virtio devices should never be unplugged at boot time, as they are
> > > > similar to pci passthrough devices.
> > > > 
> > > > Signed-off-by: Juergen Gross <jgross@suse.com>
> > > > Signed-off-by: Vikram Garhwal <vikram.garhwal@amd.com>
> > > 
> > > Hm, do your virtio NICs still actually *work* after that? Or are they
> > > all disconnected from their netdev peers? 
> > > 
> > > I suspect you're going to want a variant of
> > > 20231025145042.627381-19-dwmw2@infradead.org/T/#u">https://lore.kernel.org/qemu-devel/20231025145042.627381-19-dwmw2@infradead.org/T/#u
> > > which also leave the peers of your virtio devices intact?
> > 
> > Hi David, device unplug is an x86-only thing (see the definition of
> > xen_emul_unplug in Linux under arch/x86/xen/platform-pci-unplug.c) I
> > suspect Vikram who is working on ARM hasn't tested it.
> 
> Ah, I had assumed there was something else coming along later which
> would make it actually get used. 
> 
> > Vikram, a simple option is to drop this patch if you don't need it.
> 
> That works. Although I may revive it in that case. 
> 
Hopefully, Juergen is also okay with dropping the patch. Then, i will remove it
from v3.

Thanks David & Stefano!