Hi, [Sorry, I was unable to respond earlier.] On Wednesday 01 February 2006 11:55, Pavel Machek wrote: > > This is an experimantal patch aimed at the "unable to freeze processes under > > load" problem. > > > > On my box the 2.6.16-rc1-mm4 kernel with this patch applied survives the > > "dd if=/dev/hda of=/dev/null" test. > > What filesystem? ext2 vs. ext3 is very different. Just the entire disk. > I can fix ext2 by > just upping the timeout. ext3 is harder, because of the journalling > thread. Maybe I'll take the sledgehammer approach and just freeze all > the user tasks first... I tried to do the "small" approach and just > fix the journalling code... > > I'm not sure what problem the usermodehelper code is trying to > solve... why are usermodehelpers special? They may be waited for uninterruptilby, so we can get an unfreezable proces if we freeze one of them. Actually I think I made a mistake here, since call_usermodehelper_keys() should return -EBUSY rather than 0 when freezing_processes is non-zero (if we return 0, the caller gets confused, because it assumes the call has happend and has been successful, which is wrong). Greetings, Rafael
