Re: proc_flush_task oops

[Dave Jones]

On Wed, Dec 20, 2017 at 12:25:52PM -0600, Eric W. Biederman wrote:
> >  > 
 > >  > If the warning triggers it means the bug is in alloc_pid and somehow
 > >  > something has gotten past the is_child_reaper check.
 > >
 > > You're onto something.
 > >
 > I am not seeing where things go wrong, but that puts the recent pid bitmap, bit
 > hash to idr change in the suspect zone.
 > 
 > Can you try reverting that change:
 > 
 > e8cfbc245e24 ("pid: remove pidhash")
 > 95846ecf9dac ("pid: replace pid bitmap implementation with IDR API")
 > 
 > While keeping the warning in place so we can see if this fixes the
 > allocation problem?

So I can't trigger this any more with those reverted.  I seem to hit a
bunch of other long-standing bugs first.  I'll keep running it
overnight, but it looks like this is where the problem lies.

	Dave