[Qemu-devel] Re: [PATCH] temporary fix for on_vcpu

[Glauber Costa]

On Fri, Sep 11, 2009 at 05:56:08PM +0200, Jan Kiszka wrote:
> Glauber Costa wrote:
> > Recent changes made on_vcpu hit the abort() path, even with the IO thread
> > disabled. This is because cpu_single_env is no longer set when we call this
> > function. Although the correct fix is a little bit more complicated that 
> > that,
> > the recent thread in which I proposed qemu_queue_work (which fixes that, 
> > btw),
> > is likely to go on a quite different direction.
> > 
> > So for the benefit of those using guest debugging, I'm proposing this simple
> > fix in the interim.
> > 
> > Signed-off-by: Glauber Costa <address@hidden>
> > ---
> >  kvm-all.c |    4 ++++
> >  1 files changed, 4 insertions(+), 0 deletions(-)
> > 
> > diff --git a/kvm-all.c b/kvm-all.c
> > index df4e849..2c24440 100644
> > --- a/kvm-all.c
> > +++ b/kvm-all.c
> > @@ -902,11 +902,15 @@ void kvm_setup_guest_memory(void *start, size_t size)
> >  #ifdef KVM_CAP_SET_GUEST_DEBUG
> >  static void on_vcpu(CPUState *env, void (*func)(void *data), void *data)
> >  {
> > +#ifdef CONFIG_IOTHREAD
> >      if (env == cpu_single_env) {
> >          func(data);
> >          return;
> >      }
> >      abort();
> > +#else
> > +   func(data);
> 
> spaces++ :) But the workaround works.
> 
> > +#endif
> >  }
> >  
> >  struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,
> 
> Unless there is hope to fix kvm in iothread mode soon, we should issue a
> warning or even disable kvm support in that setup. That is particularly
> important for 0.11-stable.
As I said, with the fixes I sent recently, it should work pretty well.