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Subject: Re: kernel BUG at drivers/scsi/scsi_lib.c:1096!
From: Mark Salter <msalter@redhat.com>
To: Laurent Dufour <ldufour@linux.vnet.ibm.com>, Michael Ellerman
 <mpe@ellerman.id.au>, Christoph Hellwig <hch@infradead.org>
Cc: "James E. J. Bottomley" <JBottomley@odin.com>, brking <brking@us.ibm.com>,
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Date: Fri, 20 Nov 2015 08:37:02 -0500
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On Fri, 2015-11-20 at 13:56 +0100, Laurent Dufour wrote:
> On 20/11/2015 13:10, Michael Ellerman wrote:
> > On Thu, 2015-11-19 at 00:23 -0800, Christoph Hellwig wrote:
> > 
> > > It's pretty much guaranteed a block layer bug, most likely in the
> > > merge bios to request infrastucture where we don't obey the merging
> > > limits properly.
> > > 
> > > Does either of you have a known good and first known bad kernel?
> > 
> > Not me, I've only hit it one or two times. All I can say is I have hit it in
> > 4.4-rc1.
> > 
> > Laurent, can you narrow it down at all?
> 
> I'm trying bisect it but it's very time consuming, and I think I missed
> some bad kernel because I didn't let enough time to the system to panic.
> 
> But I'm still on...
> 
I usually hit it at boot time. Maybe one out of five times. I'll take a stab
at bisecting today...