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Date: Mon, 24 Oct 2005 18:58:50 +0200
From: Marc Olzheim <marcolz@stack.nl>
To: Daniel Eischen <deischen@freebsd.org>
Message-ID: <20051024165850.GA28694@stack.nl>
References: <20051024144529.GP22568@ilse.net>
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Cc: Marc Olzheim <marcolz@stack.nl>, freebsd-threads@freebsd.org,
	Marc Olzheim <marcolz@ilse.net>, David Xu <davidxu@freebsd.org>,
	Sven Berkvens-Matthijsse <sven@ilse.net>
Subject: Re: threads/76690: fork hang in child for (-lc_r & -lthr)
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On Mon, Oct 24, 2005 at 12:41:01PM -0400, Daniel Eischen wrote:
> > But then the free() in the child process may be using an unstable
> > state of the malloc system (because if you don't acquire the lock
> > before the fork(), malloc() may be busy in the middle of the fork()).
>=20
> I don't think that can happen because libc_r will not switch out
> a thread that is in a critical region (and libc locks are critical
> regions) until it leaves the region.

Well, that would be the idea, but GDB traces prove otherwise... :P
And that's why the patch prevents the test program in the PR from
hanging.

Marc

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