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Date: Fri, 6 Sep 2002 17:39:55 +0200 (CEST)
From: Ingo Molnar <mingo@elte.hu>
Reply-To: Ingo Molnar <mingo@elte.hu>
To: Paul Larson <plars@linuxtestproject.org>
Cc: Linus Torvalds <torvalds@transmeta.com>,
       lkml <linux-kernel@vger.kernel.org>
Subject: Re: pid_max hang again...
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On 6 Sep 2002, Paul Larson wrote:

> It looks like this change dropped us back to the same error all this was
> originally supposed to fix.  When you hit PID_MAX, get_pid() starts
> looping forever looking for a free pid and hangs.  I could probably make
> my original fix work on this very easily if you'd like.

yes please send a patch for this. Reintroduction of the looping bug was
unintended.

> I wonder though, would it be possible to do this in a more simple way by
> just throttling max_threads back to something more sane if it gets
> defaulted too high?  Since it gets checked before we even get to the
> get_pid call in copy_process().  That would keep the number of processes
> down to a sane level without the risk.

this is a good approach as well, but now pid_max can be adjusted runtime
so truncating max_threads as a side-effect looks a bit problematic. We
should rather fail the fork() cleanly.

	Ingo

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