Re: [Qemu-discuss] Longer time to detach device in q35

[Han Han]

On Sun, Apr 28, 2019 at 7:20 PM Maxim Levitsky <address@hidden> wrote:

> I 'think' that this is due to the fact that Q35 uses the PCIe hotplug,
> which was
> done for real life PCIe hotplug which involves operator pressing a button,
> and
> then waiting for confirmation.
>
> The spec allows the operator to change his mind during 5 second timeout (or
> something similiar).
>
> Now what qemu does on hot unplug, is that it presses that button
> logically, but
> then the guest waits the 5 seconds before it acts upon it as written in the
> spec.
>
> I am a little confused about why it is designed as this way. Could you
please show me the related pcie spec reference link or the qemu code of
this function?

> The 'pc' machine either uses acpi or older 'standard pci hotplug
> controller'
> whic might lack this 'feature'
>
> I am adding Michael here, as I remember that he mentioned this once.
>
> Best regards,
>         Maxim Levitsky
>
>

-- 
Best regards,
-----------------------------------
Han Han
Quality Engineer
Redhat.

Email: address@hidden
Phone: +861065339333