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From: Frans Pop <elendil@planet.nl>
To: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com>
Subject: Re: [PATCH] VM, x86, PAT: Change implementation of is_linear_pfn_mapping
Date: Thu, 12 Mar 2009 06:45:42 +0100
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On Thursday 12 March 2009, Pallipadi, Venkatesh wrote:
> Thanks for testing this. I don't seem to reproduce this on any of my
> test systems with this patch on either tip or latest git. Do you see
> the hang on every boot or once in a while? 

The problem only occurs after some time. In the case shown in the log the 
system ran fine for 15 minutes and then triggered the oops.

In another case I was running VirtualBox. It ran fine for some time but 
the system hung when I tried to close the guest system.

> Are things stable with nopat?

Yes. Seen no problems since booting with 'nopat' and done a successful 
suspend/resume. With 'pat' I saw the problem 3 times after a short period 
of use.

On Thursday 12 March 2009, you wrote:
> Thinking about it a bit more, the usage of VM_NONLINEAR flag in
> this patch may be conflicting with some expectation in
> mm code, that may be resulting in above oops. Let me
> spend some more time on this and get back to you.

Thanks.