Re: [PATCH v4 1/1] Add suspend support for virtio PCI devices

[Jason Wang <jasowang@redhat.com>]

On Fri, Feb 16, 2024 at 4:25âPM David Stevens <stevensd@chromium.org> wrote:
>
> Add a virtio power management PCI capability to allow drivers to suspend
> virtio PCI devices. This allows drivers to suspend devices at the virtio
> level before suspending them at the PCI transport layer. This allows
> drivers to do a two phase suspend, which prevents notifications from
> being ignored or lost if interrupts are reconfigured at the PCI
> transport layer immediately before or after the device is put into the
> PCI PM D3 low power state.
> ---
>  transport-pci.tex | 51 +++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>

I would like to know how the two phase suspend can prevent the loss of
notification or interrupt. Or for example, if it can be workaround at
the driver level.

Thanks