[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH] acpi: pcihp: make pending delete expire in 5sec
From: |
Igor Mammedov |
Subject: |
Re: [PATCH] acpi: pcihp: make pending delete expire in 5sec |
Date: |
Tue, 4 Apr 2023 10:30:55 +0200 |
On Tue, 4 Apr 2023 09:03:59 +0200
Gerd Hoffmann <kraxel@redhat.com> wrote:
> Hi,
>
> > > Allowing pending delete expire brings ACPI PCI hotplug on par
> > > with native PCIe unplug behavior [1] which in its turn refers
> > > back to ACPI PCI hotplug ability to repeat unplug requests.
>
> > A bit concerned about how this interacts with failover,
> > and 5sec is a lot of time that I hoped we'd avoid with acpi.
> > Any better ideas of catching such misbehaving guests?
>
> The 5sec are coming from the pcie spec: The hot-unplug request can be
> canceled within 5 seconds by pressing the button again. The problem here
> is that both hotplug and hot-unplug use the same signaling path, so we
> really have to wait the 5 seconds to avoid the OS mis-interpreting the
> button press as 'cancel' event.
Any pointer to spec?
Does it apply to SHPC too?
(/me thinking about moving pending_delete check to PCIe only code)
>
> ACPI hotplug hasn't this problem. A unplug request is a unplug request,
> period. And it can't be canceled. So it should be possible to use a
> shorter period. Possibly even no delay at all.
>
> take care,
> Gerd
>
Re: [PATCH] acpi: pcihp: make pending delete expire in 5sec, Igor Mammedov, 2023/04/04
Re: [PATCH] acpi: pcihp: make pending delete expire in 5sec, Michael S. Tsirkin, 2023/04/04
Re: [PATCH] acpi: pcihp: make pending delete expire in 5sec, Igor Mammedov, 2023/04/05