On Sun, 6 Mar 2011, KOSAKI Motohiro wrote: > > When we check that task has flag TIF_MEMDIE, we forgot check that > > it has mm. A task may be zombie and a parent may wait a memor. > > > > v2: Check that task doesn't have mm one time and skip it immediately > > > > Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx> > > This seems incorrect. Do you have a reprodusable testcasae? > Your patch only care thread group leader state, but current code > care all thread in the process. Please look at oom_badness() and > find_lock_task_mm(). > That's all irrelevant, the test for TIF_MEMDIE specifically makes the oom killer a complete no-op when an eligible task is found to have been oom killed to prevent needlessly killing additional tasks. oom_badness() and find_lock_task_mm() have nothing to do with that check to return ERR_PTR(-1UL) from select_bad_process(). Andrey is patching the case where an eligible TIF_MEMDIE process is found but it has already detached its ->mm. In combination with the patch posted to linux-mm, oom: prevent unnecessary oom kills or kernel panics, which makes select_bad_process() iterate over all threads, it is an effective solution. Thanks. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>