Re: mm, oom_reaper: How to handle race with oom_killer_disable() ?

[Michal Hocko]

On Mon 13-06-16 13:19:43, Michal Hocko wrote:
[...]
> I am trying to remember why we are disabling oom killer before kernel
> threads are frozen but not really sure about that right away.

OK, I guess I remember now. Say that a task would depend on a freezable
kernel thread to get to do_exit (stuck in wait_event etc...). We would
simply get stuck in oom_killer_disable for ever. So we need to address
it a different way.

One way would be what you are proposing but I guess it would be more
systematic to never call exit_oom_victim on a remote task.  After [1] we
have a solid foundation to rely only on MMF_REAPED even when TIF_MEMDIE
is set. It is more code than your patch so I can see a reason to go with
yours if the following one seems too large or ugly.

[1] http://lkml.kernel.org/r/1466426628-15074-1-git-send-email-mhocko@xxxxxxxxxx

What do you think about the following?
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