On Wednesday, September 25, 2013 02:52:26 PM Kyungmin Park wrote: > On Tue, Aug 20, 2013 at 9:41 PM, Rafael J. Wysocki <r...@sisk.pl> wrote: > > On Tuesday, August 20, 2013 08:27:27 AM Tejun Heo wrote: > >> On Tue, Aug 20, 2013 at 02:34:14PM +0200, Rafael J. Wysocki wrote: > >> > On Tuesday, August 20, 2013 08:22:00 AM Tejun Heo wrote: > >> > > On Tue, Aug 20, 2013 at 02:30:18PM +0200, Rafael J. Wysocki wrote: > >> > > > > So, I don't think we can simply turn TASK_UNITERRUPTIBLE to > >> > > > > TASK_KILLABLE at this point. We really need to strictly define > >> > > > > where > >> > > > > a task can freeze before being able to do anything like this. > >> > > > > >> > > > But we could do that for user space tasks I suppose? > >> > > > >> > > Even for userland tasks, we don't know where the task is stuck at. I > >> > > think there are enough freeze points in the kernel which are in the > >> > > middle of something which can be used by userland tasks excuting some > >> > > syscall. We need to collect all those sites into well defined trap > >> > > points before doing this. > >> > > >> > OK, thanks! > >> > >> I scanned through try_to_freeze() users and it seems like we don't > >> have that many which can be hit by userland tasks. I think it should > >> be doable to audit all the users, remove the ones which can be invoked > >> by userland and make try_to_freeze() whine loudly if it's running off > >> a userland task except from well-defined spots. > > > > Which might be worth doing anyway to be sure we know what's going on. > > > >> Anyways, we need to ensure that userland task doesn't get stuck deep in the > >> kernel before allowing this. > > > > Agreed. > > Are there any update? we need this feature to kill frozen app easily. > Don't need to thaw app to kill.
No updates, but the above pretty much describes what needs to be done. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
