Re: [vlan_device_event] BUG: unable to handle kernel paging request at 6b6b6ccf

[Fengguang Wu]

On Wed, Nov 08, 2017 at 10:34:10PM -0800, Cong Wang wrote:
> On Wed, Nov 8, 2017 at 7:12 PM, Fengguang Wu <fengguang.wu@xxxxxxxxx> wrote:
> > Hi Alex,
> >
> > > So looking over the trace the panic seems to be happening after a
> > > decnet interface is getting deleted. Is there any chance we could try
> > > compiling the kernel without decnet support to see if that is the
> > > source of these issues? I don't know if anyone on the Intel Wired Lan
> > > team is testing with that enabled so if we can eliminate that as a
> > > possible cause that would be useful.
> >
> >
> > Sure and thank you for the suggestion!
> >
> > It looks disabling DECNET still triggers the vlan_device_event BUG.
> > However when looking at the dmesgs, I find another warning just before
> > the vlan_device_event BUG. Not sure if it's related one or independent
> > now-fixed issue.
>
> Those decnet symbols are probably noises.

Yes it's not related to CONFIG_DECNET.

> How do you reproduce it? And what is your setup? Vlan device on
> top of your eth0 (e1000)?

It can basically be reproduced in one of our test machines --
lkp-wsx03, which is a Westmere EX server.

The test boots an openwrt image in QEMU and run trinity for minutes.

Here is the openwrt image:

https://github.com/0day-ci/lkp-qemu/blob/master/osimage/openwrt/openwrt-i386-2016-03-16.cgz

I don't know how openwrt deals with VLAN. :)

Thanks,
Fengguang