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Date: Thu, 20 Oct 2016 09:17:50 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Ingo Molnar <mingo@kernel.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: bio linked list corruption.
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On Thu, 20 Oct 2016, Ingo Molnar wrote:
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> > So I don't think it's related. Yours looks like some subtle timer base
> > race. It smells like a locking problem with timers. I'm not seeing
> > what it might be, but it *might* have been fixed by doing the
> > TIMER_MIGRATING bit right in add_timer_on() (commit 22b886dd1018).

4.1 does not have the new fangled timer wheel. So 22b886dd1018 is
irrelevant.

> > Adding some timer people just in case, but I don't think your 4.1
> > report is related.

This looks like one of the classic issues where an enqueued timer gets
freed/reinitialized or otherwise manipulated. So yes, Ingos recommendation
for debugging is the right thing to do.
 
Thanks,

	tglx