Re: [PATCH] pci: Refuse to hotplug PCI Devices when the Guest OS is not ready

[David Gibson]

On Fri, 23 Oct 2020 09:26:48 +0300
Marcel Apfelbaum <marcel.apfelbaum@gmail.com> wrote:

> Hi Michael,
> 
> On Thu, Oct 22, 2020 at 6:01 PM Michael S. Tsirkin <mst@redhat.com> wrote:
> 
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> Simplistic does not mean wrong or incorrect.
> I fail to see why it is not enough.
> 
> What QEMU can do better? Wait an unbounded time for the blinking to finish?

It certainly shouldn't wait an unbounded time.  But a wait with timeout
seems worth investigating to me.

> What if we have a buggy guest with a kernel stuck in blinking?
> Is QEMU's responsibility to emulate the operator itself? Because the
> operator
> is the one who is supposed to wait.
> 
> 
> Thanks,
> Marcel
> 
> [...]


-- 
David Gibson <dgibson@redhat.com>
Principal Software Engineer, Virtualization, Red Hat

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