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Message-ID: <466BFE92.6000804@FreeBSD.org>
Date: Sun, 10 Jun 2007 15:37:22 +0200
From: Attilio Rao <attilio@FreeBSD.org>
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Sender: Attilio Rao <asmrookie@gmail.com>
Cc: Randall Stewart <rrs@cisco.com>, freebsd-current@freebsd.org
Subject: Re: Don't know what I was doing but...
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Attilio Rao wrote:
> Randall Stewart wrote:
>> Hi all:
>>
>> I have a fairly recent current.. like yesterday I think.. and
>> I just saw this tumble out (I usually run with witness and invariants
>> on in my laptop now :-D)
>>
>> lock order reversal:
>>  1st 0xc0b79f70 sched lock (sched lock) @ kern/sched_4bsd.c:846
>>  2nd 0xc0bec658 descriptor tables (descriptor tables) @ 
>> i386/i386/sys_machdep.c:363
> 
> Mm, since dt_lock is a leaf mutex, the opposite case seems quite 
> impossible, so I expect this would be the result of some other bug... if 
>  next cvsup doesn't fix it, just let me know and I will look into this.

More precisely, I'd like to better study effects recent thread_lock 
introduction had on witness rules.

Attilio