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

Jason Gunthorpe
2025-09-29T17:46:30Z

On Tue, Sep 16, 2025 at 12:45:10AM -0700, Chris Li wrote:
> static int pci_liveupdate_prepare(void *arg, u64 *data)
> {
> + LIST_HEAD(requested_devices);
> +
> pr_info("prepare data[%llx]\n", *data);
> +
> + pci_lock_rescan_remove();
> + down_write(&pci_bus_sem);
> +
> + build_liveupdate_devices(&requested_devices);
> + cleanup_liveupdate_devices(&requested_devices);
> +
> + up_write(&pci_bus_sem);
> + pci_unlock_rescan_remove();
> return 0;
> }

This doesn't seem conceptually right, PCI should not be preserving
everything. Only devices and their related hierarchy that are opted
into live update by iommufd should be preserved.

Jason