On Tue, Jul 28, 2026 at 10:10:00PM +0000, David Matlack wrote: > When a PCI device is preserved across a Live Update, all of its upstream > bridges up to the root port must also be preserved. This enables the PCI > core and any drivers bound to the bridges to manage bridges correctly > across a Live Update. > > Notably, this will be used in subsequent commits to ensure that > preserved devices can continue performing memory transactions without a > disruption or change in routing. > > To preserve bridges, the PCI core tracks the number of downstream > devices preserved under each bridge using a reference count in struct > pci_dev_ser. This allows a bridge to remain preserved until all its > downstream preserved devices are unpreserved or finish their > participation in the Live Update.
This seems to hint that we're going to allow bridge reconfiguration in some cases, e.g., for hot-adds. The simplest case is "leave config of all bridges the same", and I thought that was what the previous patch commit log said. What's the benefit added by this patch?
