Re: 2.6.14-rt15: cannot build with !PREEMPT_RT

Lee Revell
2005-12-09T01:04:08Z

On Tue, 2005-11-29 at 10:32 +0100, Ingo Molnar wrote:
> * Ingo Molnar <mingo@elte.hu> wrote:
>
> > * Lee Revell <rlrevell@joe-job.com> wrote:
> >
> > > On Mon, 2005-11-28 at 17:40 -0500, Lee Revell wrote:
> > > > 2.6.11-RT-V0.7.40-04 works
> > >
> > > and 2.6.12-RT-V0.7.51-28 does not.
> >
> > thanks. I have further narrowed it down from this point: your .config
> > breaks from the 51-01 to the 51-02 kernel (on my testbox).
>
> ok, fixed this one, it was the CURRENT_PTR optimization on UP that broke
> if 4K stacks were enabled. (i disabled the optimization for now)
>
> But interestingly, your .config unearthed 2 other serious bugs (!) as
> well: the spin_unlock_irq() upon printk was incorrect for !PREEMPT_RT,
> and there was an assert introduced by the get-rid-of-bitlocks ext3
> patches which was invalid on UP && !PREEMPT_RT. We had these bugs for
> quite some time.
>
> I've released -rt21 with these fixes, does it work better for you?

Ingo,

We are unable to build a similar .config (PREEMPT_DESKTOP with soft and
hardirq preemption disabled) on x86-64:

In file included from include/linux/mm.h:15,
from kernel/printk.c:20:
include/linux/fs.h: In function `lock_super':
include/linux/fs.h:849: warning: implicit declaration of function `down'
include/linux/fs.h: In function `unlock_super':
include/linux/fs.h:855: warning: implicit declaration of function `up'

Let me know if you need the exact .config

Lee