Re: [BUG] kvm crashes in 2.6.28-rc6-00007-ged31348

Steven Rostedt
2008-12-02T20:48:57Z

On Tue, 2008-12-02 at 22:38 +0200, Avi Kivity wrote:
> Steven Rostedt wrote:
> > The following must be available without recursion for the function
> > tracer to work:
> >
> > local_irq_save/restore
> > smp_processor_id
> > preempt_enable/disable_notrace
> > atomic_inc/dec
> >
>
> In arch/x86/kvm/svm.c, function svm_vcpu_run(), everything between the
> vmrun instruction and the call to load_host_msrs() is executed without a
> live pda, so no smp_processor_id(). Could easily be fixed by
> rearranging things.

That would be best, but if you have trouble, you could surround the
trouble area with a: tracing_stop(); tracing_start(); That will prevent
tracing within those locations. The function tracer will still be
called, but it will exit the function without doing anything else.

Note: that stops tracing on all CPUS, not just the CPU that called it.

-- Steve