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Date: Thu, 31 Jan 2008 15:58:24 -0600
From: Scott Wood <scottwood@freescale.com>
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To: Nathan Lynch <ntl@pobox.com>
Subject: Re: Kernel oops while duming user core.
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Scott Wood wrote:
> Nathan Lynch wrote:
>> Is the crashing program multithreaded?  The first report had firefox
>> triggering the oops.
> 
> OK, I've got a test program that triggers it now.  I'll see if I can 
> figure out what's going on.

The problem seems to be that update_mmu_cache() is called on a guard 
page with no access rights.

Changing update_mmu_cache() to always call flush_dcache_icache_page() 
fixes it, though a better performing fix would probably be to add an 
exception table entry for the dcbst.

-Scott