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: > > > 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. > > Hmm. Please have a look at the appended patch. > > I have removed the warning from device_del() and used list_empty() to detect > removed devices in the .suspend() routines. Is that viable? It's not good. The warning in device_del() is vital. It's what will tell people where the problem is when a deadlock occurs during system resume because some driver has mistakenly tried to unregister a device at the wrong time. It would have pointed immediately to the msr driver in the case of the bug Andrew found, for instance. If you can figure out a way to disable the warning in device_del() for just the one device being unregistered by device_pm_destroy_suspended(), I suppose that would be okay. Alan Stern - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
