Re: endless loop in native_flush_tlb_others in smp_64.c

[Thomas Gleixner <tglx@linutronix.de>]

On Tue, 11 Mar 2008, Jike Song wrote:
> >  Most of them happend in X.org so at first I thought it had something to do
> >  with the NVIDIA module... BUT, one time it froze "a way before" the module
> >  could get loaded (and desynced my raid.......).
> >
> >  ---
> >  SYSRQ-P revealed that the CPU were looping inside:
> >
> >  smp_64.c native_flush_tlb_others:
> >  assembler code:
> >  < 1ee:   f3 90                   pause
> >  < 1f0:   f6 45 00 03             testb  $0x3,0x0(%rbp)
> >  < 1f4:   75 f8                   jne    1ee <native_flush_tlb_others+0x5f>
> >
> >  also known as: (in C)
> >
> >  while (!cpus_empty(f->flush_cpumask))
> >         cpu_relax();
> >
> >  So... has anyone a good idea what's happening here exactly? Or is there
> >  already another topic or even a patch available?

Any chance that you can capture SYSRQ-T output via serial or
netconsole, so we can see the stacktrace and what the other CPUs are
doing, if they are doing anything.

Thanks,
	tglx