On Sat, 5 Jan 2008, Rafael J. Wysocki wrote: > On Saturday, 5 of January 2008, Alan Stern wrote: > > On Sat, 5 Jan 2008, Rafael J. Wysocki wrote: > > > > > > Another thing to watch out for: Just in case somebody ends up calling > > > > destroy_suspended_device(dev) from within dev's own resume method, you > > > > should interchange the resume_device() and the list_move_tail() > > > > calls in dpm_resume(). > > > > > > However, if we unregister them all at once after releasing pm_sleep_rwsem, > > > that shouldn't be necessary, right? > > > > It's still necessary, because destroy_suspended_device() still has to > > move the device from one list to another. You don't want it to end up > > on the dpm_locked list. > > Hmm. That means we'd have to do the same thing in dpm_power_up() in case > someone calls destroy_suspended_device() from resume_device_early(dev). Yes. > Still, even doing that is not enough, since someone can call > destroy_suspended_device() from a .suspend() routine and then the device > will end up on a wrong list just as well. That should never happen. The whole idea of destroy_suspended_device() is that the device couldn't be resumed and in fact should be unregistered because it is no longer working or no longer present. A suspend routine won't detect this sort of thing since it doesn't try to resume the device. But it wouldn't hurt to mention in the kerneldoc that destroy_suspended_device() is meant to be called only during a system resume. Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
