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Date: Mon, 16 Mar 2015 10:01:12 -0400
From: Peter Hurley <peter@hurleysoftware.com>
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To: Pranith Kumar <bobby.prani@gmail.com>,
 Michael Ellerman <mpe@ellerman.id.au>
Subject: Re: linux panic on 4.0.0-rc4
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On 03/16/2015 09:30 AM, Pranith Kumar wrote:
> On Mon, Mar 16, 2015 at 4:16 AM, Michael Ellerman <mpe@ellerman.id.au> wrote:
>> On Mon, 2015-03-16 at 01:34 -0400, Pranith Kumar wrote:
>>> On Mon, Mar 16, 2015 at 1:11 AM, Pranith Kumar <bobby.prani@gmail.com> wrote:
>>>> Hello,
>>>>
>>>> I have a power mac mini 32-bit system.
>>>>
>>> ...
>>>> You can see the panic message here: http://imgur.com/s1lH15g. (there
>>>> is no log and I have no serial console).
>>>
>>> There was some debug code in there when it hit. The actual hang seems
>>> to be in printk_late_init(). It does not return from this. May be this
>>> is a hint?
>>
>> That is where the boot consoles get disabled and it switches to the "real"
>> console. It suggests that the system is not "hung" there but you just lost
>> output.
>>
>> Try booting with "keep_bootcon" ?
> 
> I tried this and got to the same place as in the first mail:
> http://imgur.com/s1lH15g
> 
> There is a kernel panic with the message printed. Any more suggestions
> to how to debug this?

git bisect.

Regards,
Peter Hurley