Re: Regression with a0747a859ef6 ("bdi: add error handle for bdi_debug_register")

[Bruno Wolff III]

On Thu, Dec 21, 2017 at 10:02:15 -0700,
 Jens Axboe <axboe@xxxxxxxxx> wrote:
> On 12/21/17 9:42 AM, Bruno Wolff III wrote:
> > On Thu, Dec 21, 2017 at 23:48:19 +0800,
> >   weiping zhang <zwp10758@xxxxxxxxx> wrote:
> > > > output you want. I never saw it for any kernels I compiled myself. Only when
> > > > I test kernels built by Fedora do I see it.
> > > see it every boot ?
> >
> > I don't look every boot. The warning gets scrolled of the screen. Once I see
> > the CPU hang warnings I know the boot is failing. I don't always look
> > at journalctl later to see what's there.
>
> I'm going to revert a0747a859ef6 for now, since we're now 8 days into this
> and no progress has been made on fixing it.

One important thing I have just found is that it looks like the problem 
only happens when booting in enforcing mode. If I boot in permissive 
mode it does not happen. My home machines are currently set to boot in 
permissive mode and I'll test this evening to see if I can reproduce the 
problem if I change them to enforcing mode. If so I'll be able to do lots 
of testing during my vacation.