On Wed, 24 Apr 2013 17:42:16 +0200 Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > On 04/24, Michal Hocko wrote: > > > > On Wed 24-04-13 16:55:14, Oleg Nesterov wrote: > > > > > > But I can't understand how this patch can fix the problem, I think it > > > can't. > > > > > > From the changelog: > > > > > > When SIGKILL is sent to a task, it's also sent to all tasks in the same > > > threadgroup. This information can be used to prevent triggering further > > > oom killers for this threadgroup and avoid the infinite loop. > > > ^^^^^^^^^^^^^^^^^^^^^^^ > > > > > > How?? > > > > I guess it assumes that fatal_signal_pending() is still true even when > > the process is unhashed already. > > No, it is not (in general). The task can dequeue this SIGKIL and then > exit. But this doesn't matter. > > > Which sounds like a workaround to me. > > The task can do everything after we check PF_EXITING or whatever else. > Just suppose it is alive and running, but before we take tasklist_lock > it exits and removes itself from list. > > But wait, I forgot that "p" is not necessarily the main thread, so > the patch I sent is not enough... > > Oh, and this reminds me again but we can race with exec... but this > is mostly theoretical. should be fixed anyway. > > I'll try to think more tomorrow. I need to recall the previous discussion > at least. Where does this leave us with Sergey's patch? "Still good, but requires new changelog"? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>