On Tuesday, 31 July 2007 20:17, Alan Stern wrote: > On Tue, 31 Jul 2007, Cornelia Huck wrote: > > > On Tue, 31 Jul 2007 11:11:50 -0400 (EDT), > > Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > I wonder if device_move() shouldn't change the order of entries in the > > > dpm_active list so that the new parent (and all its ancestors) get > > > moved up ahead of the device's position? But that might cause other > > > problems... > > > > This may be necessary if walking the list is the single determining > > factor to the order of suspend/resume. > > It is. > > > Are there any other dependencies > > not covered by time of registration order? I would imagine those needed > > moving devices on the dpm_active list as well... > > I'm not sure what you mean. Devices where A needs to be suspended > before B even though A was discovered first? I'm not aware of anything > like that, other than your case and Marcel's. Right now there's no > code in the PM core to handle such things. > > There is a dependency in the USB subsystem, wherein I need an EHCI > controller to be _resumed_ after its companion UHCI or OHCI > controllers. This works out, thanks to the fact that manufacturers > tend to give the EHCI controller the largest PCI function number and > the Linux PCI core enumerates functions in numerical order. This is > just pure luck, however, and if anything changed I'd have to add an > explicit fix. That sounds really worrying to me. The design appears to be very fragile if such things are possible, even in theory. Greetings, Rafael -- "Premature optimization is the root of all evil." - Donald Knuth _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
