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Date: Wed, 24 Oct 2007 21:44:28 -0700
From: Alfred Perlstein <alfred@freebsd.org>
To: David Xu <davidxu@FreeBSD.org>
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Cc: cvs-src@FreeBSD.org, src-committers@FreeBSD.org,
	Julian Elischer <julian@FreeBSD.org>, cvs-all@FreeBSD.org
Subject: Re: cvs commit: src/sys/kern kern_fork.c
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* David Xu <davidxu@FreeBSD.org> [071024 19:40] wrote:
> Alfred Perlstein wrote:
> 
> >>thread_suspend_check() with SINGLE_BOUNDARY is used is only called
> >>in userret() where I don't think any code is still using the p_fd.
> >
> >
> >This is not an acceptable solution as it will deadlock unless all
> >threads exit the kernel.
> >
> 
> Where is deadlock ? thread_single(SINGLE_BOUNDARY) does not suspend
> sleeping thread, it will interrupt it.

If it does, it will give awful semantics, it's better to just
disallow this action with threads until the code is fixed.

-- 
- Alfred Perlstein