From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S3000991AbdDZOFa (ORCPT <rfc822;w@1wt.eu>);
        Wed, 26 Apr 2017 10:05:30 -0400
Received: from mail-oi0-f47.google.com ([209.85.218.47]:36458 "EHLO
        mail-oi0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S3000976AbdDZOFW (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 26 Apr 2017 10:05:22 -0400
MIME-Version: 1.0
In-Reply-To: <1493163594.26622.11.camel@hpe.com>
References: <20170425230413.363-1-toshi.kani@hpe.com> <CAPcyv4jNpCc=qCsRM0-U3Ov=iFn2e_n53_ZgPdDV3pttS0P9Ew@mail.gmail.com>
 <1493163594.26622.11.camel@hpe.com>
From: Dan Williams <dan.j.williams@intel.com>
Date: Wed, 26 Apr 2017 07:05:20 -0700
Message-ID: <CAPcyv4j97ff6H9Fc7=vVwjBOgjZHyEiEhcf+4PE4MkwLOEoCmg@mail.gmail.com>
Subject: Re: [PATCH] pmem: fix a NULL pointer BUG in nd_pmem_notify
To: "Kani, Toshimitsu" <toshi.kani@hpe.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-nvdimm@lists.01.org" <linux-nvdimm@ml01.01.org>,
        "Verma, Vishal L" <vishal.l.verma@intel.com>
Content-Type: text/plain; charset=UTF-8
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Apr 25, 2017 at 4:40 PM, Kani, Toshimitsu <toshi.kani@hpe.com> wrote:
> On Tue, 2017-04-25 at 16:07 -0700, Dan Williams wrote:
>> On Tue, Apr 25, 2017 at 4:04 PM, Toshi Kani <toshi.kani@hpe.com>
>> wrote:
>> > The following BUG was observed when nd_pmem_notify() was called
>> > for a BTT device.  The use of a pmem_device pointer is not valid
>> > with BTT.
>> >
>> >  BUG: unable to handle kernel NULL pointer dereference at
>> > 0000000000000030
>> >  IP: nd_pmem_notify+0x30/0xf0 [nd_pmem]
>> >  Call Trace:
>> >   nd_device_notify+0x40/0x50
>> >   child_notify+0x10/0x20
>> >   device_for_each_child+0x50/0x90
>> >   nd_region_notify+0x20/0x30
>> >   nd_device_notify+0x40/0x50
>> >   nvdimm_region_notify+0x27/0x30
>> >   acpi_nfit_scrub+0x341/0x590 [nfit]
>> >   process_one_work+0x197/0x450
>> >   worker_thread+0x4e/0x4a0
>> >   kthread+0x109/0x140
>> >
>> > Fix nd_pmem_notify() by setting nd_region and badblocks pointers
>> > properly for BTT.
>> >
>> > Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
>> > Cc: Dan Williams <dan.j.williams@intel.com>
>> > Cc: Vishal Verma <vishal.l.verma@intel.com>
>>
>>
>> Hi Toshi, how did you trigger this? I'd like to get your test into
>> the regression suite.
>
> Hi Dan,
>
> I injected an error and started an ARS scan.  Unfortunately, my test
> steps need to run on our platforms.  I think these error injection
> features can be emulated, though.

Yes, I'll try to come up with something for nfit_test.

Thanks Toshi!