Re: [regression] boot failure on alpha, bisected

Thorsten Kranzkowski
2012-10-07T19:47:36Z

On Sun, Oct 07, 2012 at 09:16:27PM +0200, Oleg Nesterov wrote:
> On 10/07, Thorsten Kranzkowski wrote:
> > On Sun, Oct 07, 2012 at 07:13:00PM +0200, Oleg Nesterov wrote:
> > > On 10/07, Oleg Nesterov wrote:
> > > >
> > > > Hmm. I know nothing about arch/alpha and I can't understand its entry.S.
> > > > But _it seems_ to me that do_notify_resume() is called with irqs disabled.
> > > > If this is true, then imho arch/alpha should be fixed.
> > > >
> > > > Before this commit task_work_run() enabled irqs, but this was the "side
> > > > effect" of spin_lock_irq/spin_unlock_irq, we should not rely on this.
> > >
> > > Could you please test the debugging patch below?
> >
> > Of course. With that patch applied the kernel (ac3d0da) boots again. The trace line
> > is printed about once a second, with values '2' and '4'.
>
> Thanks a lot Thorsten!
>
> So I'll probably send the patch which enables interrupts in
> task_work_run(). I guess this needs "if (irqs_disabled())"
> for lockdep.
>
> The question is, should I add the warning to remind that this
> arch needs a fix?

If you do, then please warn only once, otherwise there will be a lot of
warnings :-)

Thorsten

--
| Thorsten Kranzkowski Internet: dl8bcu@dl8bcu.de |
| Mobile: ++49 170 1876134 Snail: Kiebitzstr. 14, 49324 Melle, Germany |
| Ampr: dl8bcu@db0lj.#rpl.deu.eu, dl8bcu@marvin.dl8bcu.ampr.org [44.130.8.19] |