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Date: Fri, 23 Jun 2006 13:02:58 +0200 (CEST)
From: Martin Blapp <mb@imp.ch>
To: Gavin Atkinson <gavin.atkinson@ury.york.ac.uk>
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Cc: Robert Watson <rwatson@freebsd.org>, Patrick Guelat <patg@imp.ch>,
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Subject: Re: Crash with FreeBSD 6.1 STABLE of today
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Hi,

>> (kgdb) p *tp->t_session
>> Cannot access memory at address 0x0
>>
>> So here the problem is. Why is tp->t_session empty ? Maybe it has been already
>> free() earlier and we have some race here ?
>
> "Race" was exactly my conclusion last time I looked into this.
> http://docs.FreeBSD.org/cgi/mid.cgi?20041204110815.E80797
>
> Something, somewhere is playing with t_session without locking...
>

Any idea how we can track this down ? It's a very bad thing to have in 61.
And yes, the serial output is going over a serial console.

Martin