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Date: Fri, 10 Jun 2016 14:54:59 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Dmitry Vyukov <dvyukov@google.com>
cc: Ingo Molnar <mingo@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
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        Sasha Levin <sasha.levin@oracle.com>,
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        Peter Zijlstra <peterz@infradead.org>
Subject: Re: x86: bad pte in pageattr_test
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On Fri, 10 Jun 2016, Dmitry Vyukov wrote:
> Here is the second log:
> https://gist.githubusercontent.com/dvyukov/dd7970a5daaa7a30f6d37fa5592b56de/raw/f29182024538e604c95d989f7b398816c3c595dc/gistfile1.txt
> 
> I've hit only twice. The first time I tried hard to reproduce it, with
> no success. So unfortunately that's all we have.
> 
> Re logs: my setup executes up to 16 programs in parallel. So for
> normal BUGs any of the preceding 16 programs can be guilty. But since
> this check is asynchronous, it can be just any preceding program in
> the log.

Ok.
 
> I would expect that it is triggered by some rarely-executing poorly
> tested code. Maybe mmap of some device?

That's the mmap(dev) list which is common between the two log files:

vcsn
ircomm
rfkill
userio
dspn
mice
midi
sndpcmc
hidraw0
vga_arbiter
lightnvm
sr

Dunno, if that's the right direction, but exposing these a bit more might be
worth to try.

Thanks,

	tglx