Re: [PATCH v2 02/10] PCI/LUO: Create requested liveupdate device list

Chris Li
2025-10-03T21:06:37Z

On Fri, Oct 3, 2025 at 7:05 AM Jason Gunthorpe <jgg@ziepe.ca> wrote:
>
> On Thu, Oct 02, 2025 at 10:33:20PM -0700, Chris Li wrote:
> > The consideration is that some non vfio device like IDPF is preserved
> > as well. Does the iommufd encapsulate all the PCI device hierarchy? I
> > was thinking the PCI layer knows about the PCI device hierarchy,
> > therefore using pci_dev->dev.lu.flags to indicate the participation of
> > the PCI liveupdate. Not sure how to drive that from iommufd. Can you
> > explain a bit more?
>
> I think you need to start from here and explain what is minimally
> needed and identify what gets put in the luo session and what has to
> be luo global.

That means it is a bigger conversion that PCI alone, this will need to
change the LUO subsystem design. I can start from the vfio/iommufd
point of view, if the liveupdate device is driven from the
vfio/iommufd side, what is the PCI layer needed to do collaborate. It
will likely end up changing the LUO subsystem and callback design. I
will make that my starting point for the next step.

Thank you.

Chris