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Date: Thu, 25 Oct 2007 10:41:06 +0800
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To: Alfred Perlstein <alfred@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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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.

> filedescs can be refcounted per thread I think.
>