RE: [PATCH] [SCSI] libsas panic when single phy disabled on a wide port

From: "Mark Salyzyn" <mark_salyzyn@us.xyratex.com>
To: Dan Williams <dan.j.williams@intel.com>, Jack Wang <jack_wang@usish.com>
Cc: linux-scsi@vger.kernel.org, Darrick Wong <djwong@us.ibm.com>,
	Xiangliang Yu <yuxiangl@marvell.com>,
	Luben Tuikov <ltuikov@yahoo.com>,
	James Bottomley <jbottomley@parallels.com>
Subject: RE: [PATCH] [SCSI] libsas panic when single phy disabled on a wide port
Date: Mon, 3 Oct 2011 06:07:47 -0700	[thread overview]
Message-ID: <FC1F9E38C0703341A1A750524E2525A9018AE711@XYUS-EX22.xyus.xyratex.com> (raw)
In-Reply-To: <CAA9_cmdq455AZJUPNdjCrn7JT90AXZtZbGGejcpLDX3zYfu+2A@mail.gmail.com>

100% agree with Dan! In fact it is my fault for not digging deeper when
I had the duplication relatively close at hand (but production pressures
had me move on, in my defense). I definitely attacked the symptom. The
patch is a piece of hardening, which can remain as paranoia after the
root cause has properly been discovered (turned into a BUG() likely).

I have lost the resources to duplicate this problem at the moment.

Sincerely -- Mark Salyzyn

-----Original Message-----
From: dan.j.williams@gmail.com [mailto:dan.j.williams@gmail.com] On
Behalf Of Dan Williams
Sent: Friday, September 30, 2011 9:43 PM
To: Jack Wang
Cc: Mark Salyzyn; linux-scsi@vger.kernel.org; Darrick Wong; Xiangliang
Yu; Luben Tuikov; James Bottomley
Subject: Re: [PATCH] [SCSI] libsas panic when single phy disabled on a
wide port

On Thu, Sep 29, 2011 at 7:21 PM, Jack Wang <jack_wang@usish.com> wrote:
> I can reproduce this bug, so I'm ok to get this fix in.
>

Mark admits this is a band aid.  I'd like to understand the root cause
of why the port is NULL here.
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