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

On Sat, Nov 17, 2012 at 4:54 PM, Rafael Aquini [off-list ref] wrote:

On Sat, Nov 17, 2012 at 01:01:30PM -0500, Sasha Levin wrote:

quoted

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