Re: [PATCH] PCI: Add pci shutdown ability

Adam Belay
2005-04-25T20:19:28Z

On Mon, Apr 25, 2005 at 03:23:09PM -0400, Jeff Garzik wrote:
> Greg KH wrote:
> >Well it seems that people are starting to want to hook the reboot
> >notifier, or the device shutdown facility in order to properly shutdown
> >pci drivers to make kexec work nicer.
> >
> >So here's a patch for the PCI core that allows pci drivers to now just
> >add a "shutdown" notifier function that will be called when the system
> >is being shutdown. It happens just after the reboot notifier happens,
> >and it should happen in the proper device tree order, so everyone should
> >be happy.
> >
> >Any objections to this patch?
>
> Traditionally the proper place -has- been
> * the reboot notifier
> * the ->remove hook (hot unplug, and module remove)
>
> which covers all the cases.
>
> Add a ->shutdown hook is more of a hack. If you want to introduce this
> facility in a systematic way, introduce a 'kexec reboot' option which
> walks the device tree and shuts down hardware.
>
> ->shutdown is just a piecemeal, uncoordinated effort (uncoordinated in
> the sense that driver shutdowns occur in an undefined order).
>
> Jeff

I agree, though I think "->remove" may be more than we need. Another
potential use of this might be to prepare devices just before removing power.

Thanks,
Adam