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Subject: Re: 2.6.31-rc5-git2 crash on a idle system.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Sachin Sant <sachinp@in.ibm.com>
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Date: Fri, 07 Aug 2009 07:51:09 +1000
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On Thu, 2009-08-06 at 19:03 +0530, Sachin Sant wrote:
> I added few printks in the initcall debug code patch. The o/p suggests
> that by the time first initicall debug message is printed the code is
> already corrupted. Further debug suggests, when start_kernel() is
> called the code at address(0xc000000000600000) is already corrupted.
> About 28 bytes of code starting from the above address is
> overwritten. 
> 
> I will try to add few more debug statements to find the place where
> this corruption might me happening.

Hrm... start_kernel is very very early... strange. Can you double check
that the actual kernel image contains the right stuff ? Also, what
distro are you using to test that and how are you booting that kernel ?

You can always add something to prom_init.c to test (though beware you
aren't relocated yet so you need to offset the addresses).

Cheers,
Ben.