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Subject: Re: oops in 2.4.4-ac9 (mm/slab.c)
To: afranck@gmx.de (Andreas Franck)
Date: Thu, 17 May 2001 01:19:34 +0100 (BST)
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <Pine.LNX.4.31.0105170103380.2918-100000@dg1kfa.ampr.org> from "Andreas Franck" at May 17, 2001 01:05:26 AM
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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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> when this happened, and I was not able to log in onto any console or
> terminal afterwards (probably because tty_open failed very miserably
> on the way?)

Its a deliberate debugging trap.

> #if DEBUG
>         if (cachep->flags & SLAB_POISON)
>                 if (kmem_check_poison_obj(cachep, objp))
>                         BUG();
> 			^^^^^^ This one is triggered

Someone freed memory and then scribbled on it. 

The first thing useful here is to know which drivers you were using shortly
before the oops