Re: [Fastboot] [PATCH] kexec: Fix CONFIG_SMP=n compilation (ia64)

[Horms <horms@verge.net.au>]

On Fri, Feb 02, 2007 at 11:01:21AM +0800, Zou, Nanhai wrote:
> > > >  void
> > > >  machine_crash_shutdown(struct pt_regs *pt)
> > > > @@ -132,11 +134,12 @@ kdump_cpu_freeze(struct unw_frame_info *
> > > >       atomic_inc(&kdump_cpu_freezed);
> > > >       kdump_status[cpuid] = 1;
> > > >       mb();
> > > > -     if (cpuid == 0) {
> > > > -             for (;;)
> > > > -                     cpu_relax();
> > > > -     } else
> > > > +#ifdef CONFIG_HOTPLUG_CPU
> > > > +     if (cpuid != 0)
> > > >               ia64_jump_to_sal(&sal_boot_rendez_state[cpuid]);
> > > > +#endif
> > > > +     for (;;)
> > > > +             cpu_relax();
> > > >  }
> > >
> > > I trust ia64_jump_to_sal doesn't return.
> > 
> > So do I. The main problem with the compilation seems to be that
> > ia64_jump_to_sal() only exists if CONFIG_HOTPLUG_CPU=y.
> > (include/asm-ia64/sal.h, arch/ia64/kernel/head.S)
> > 
>  This may cause problem on SN platform. 
> I remember SN requires cpu0 return to SAL rendez loop to do IRQ redirection.
> However this needs SGI people to confirm...

Does this mean that CONFIG_HOTPLUG_CPU may be required for kdump
on the SN platform?

-- 
Horms
  H: http://www.vergenet.net/~horms/
  W: http://www.valinux.co.jp/en/