Date: Thu, 12 Jun 2008 03:24:42 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Andi Kleen <andi@firstfloor.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>,
       Manfred Spraul <manfred@colorfullife.com>, linux-kernel@vger.kernel.org,
       linux-mm@kvack.org, Pekka Enberg <penberg@cs.helsinki.fi>
Subject: Re: repeatable slab corruption with LTP msgctl08
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On Thu, 12 Jun 2008 10:35:55 +0200 Andi Kleen <andi@firstfloor.org> wrote:

> BTW a great way to debug slab corruptions with LTP faster is to run with
> a slab thrasher stress module like http://firstfloor.org/~andi/crasher-26.diff

Well I tried that.  It didn't actually seem to do much (no CPU time
consumed) so I revved it up a bit: 

--- a/drivers/char/crasher.c~crasher-26-speedup
+++ a/drivers/char/crasher.c
@@ -59,7 +59,7 @@ struct mem_buf {
 static unsigned long crasher_random(void)
 {
         rand_seed = rand_seed*69069L+1;
-        return rand_seed^jiffies;
+        return (rand_seed^jiffies) & 3;
 }
 
 void crasher_srandom(unsigned long entropy)
_


But it hasn't crashed after 57 minutes.

I don't think that is how we should fix this bug ;)

I'm pretty much out of time on this one.
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