On Thu, Apr 2, 2026 at 2:29 PM Yanjun.Zhu <[email protected]> wrote: > On 3/23/26 4:57 PM, David Matlack wrote:
> > +config PCI_LIVEUPDATE > > + bool "PCI Live Update Support (EXPERIMENTAL)" > > + depends on PCI && LIVEUPDATE > > + help > > + Support for preserving PCI devices across a Live Update. This option > > + should only be enabled by developers working on implementing this > > + support. Once enough support as landed in the kernel, this option > > + will no longer be marked EXPERIMENTAL. > > + > > + If unsure, say N. > > Currently, it only supports 'n' or 'y'. Is it possible to add 'm' > (modular support)? > > This would allow the feature to be built as a kernel module. For > development > > purposes, modularization means we only need to recompile a single module > > for testing, rather than rebuilding the entire kernel. Compiling a > module should > > be significantly faster than a full kernel build. I don't think it is possible for CONFIG_PCI_LIVEUPDATE to support 'm'. pci_setup_device() (which is under CONFIG_PCI) needs to call pci_liveupdate_setup_device(), and CONFIG_PCI cannot be built as a module. This call is necessary so the PCI core knows whether a device being enumerated was preserved across a previous Live Update.
