Re: [PATCH v12 4/7] mm: introduce compaction and migration forballooned pages

From: Sasha Levin
Date: Sun Nov 18 2012 - 10:00:14 EST


On Sat, Nov 17, 2012 at 4:54 PM, Rafael Aquini <aquini@xxxxxxxxxx> wrote:
> On Sat, Nov 17, 2012 at 01:01:30PM -0500, Sasha Levin wrote:
>>
>> I'm getting the following while fuzzing using trinity inside a KVM tools guest,
>> on latest -next:
>>
>> [ 1642.783728] BUG: unable to handle kernel NULL pointer dereference at 0000000000000194
>> [ 1642.785083] IP: [<ffffffff8122b354>] isolate_migratepages_range+0x344/0x7b0
>>
>> My guess is that we see those because of a race during the check in
>> isolate_migratepages_range().
>>
>>
>> Thanks,
>> Sasha
>
> Sasha, could you share your .config and steps you did used with trinity? So I
> can attempt to reproduce this issue you reported.

Basically try running trinity (with ./trinity -m --quiet --dangerous
-l off) inside a disposable guest as root.

I manage to hit that every couple of hours.

Config attached.


Thanks,
Sasha

Confi

Attachment: config-sasha
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