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To: John Baldwin <jhb@FreeBSD.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Fri, 01 Apr 2005 11:20:27 CDT."
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Date: Fri, 01 Apr 2005 20:52:38 +0200
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cc: William Michael Grim <wgrim@siue.edu>
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Subject: Re: 4BSD Scheduler Problem on 5.3 
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In message <200504011120.27285.jhb@FreeBSD.org>, John Baldwin writes:

>> I think we have a race in -STABLE relating to tty wakeups and
>> open/close/device teardown.  I've seen a panic relating to sio during a
>> tty close on RELENG_5 about 5-6 months ago, but was unable to get a dump.
>> Scott has since fixed dumps with twe, but I've not yet been able to get
>> the bug to recur.  I'll give it another try.
>
>Sounds very plausible.  Does Poul-Henning have any ideas?

Is this before or after my tty changes ?

There is a general nastyness about ttys/sessions/exit which I have
never really felt comfortable about.  My hope is that I have solved
it by refcounting the tty structure.

So if this is before my changes:  "Yeah, known (but rare) issue)"

If after my changes: "D**N!"

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.