Re: [PATCH 1/1] kvmclock: fix guest stop notification

[Marcelo Tosatti <mtosatti@redhat.com>]

On Thu, Sep 20, 2012 at 09:46:41AM -0300, Marcelo Tosatti wrote:
> On Thu, Sep 20, 2012 at 01:55:20PM +0530, Amit Shah wrote:
> > Commit f349c12c0434e29c79ecde89029320c4002f7253 added the guest stop
> > notification, but it did it in a way that the stop notification would
> > never reach the kernel.  The kvm_vm_state_changed() function gets a
> > value of 0 for the 'running' parameter when the VM is stopped, making
> > all the code added previously dead code.
> > 
> > This patch reworks the code so that it's called when 'running' is 0,
> > which indicates the VM was stopped.
> > 
> > CC: Eric B Munson <emunson@mgebm.net>
> > CC: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
> > CC: Andreas Färber <afaerber@suse.de>
> > CC: Marcelo Tosatti <mtosatti@redhat.com>
> > CC: Paolo Bonzini <pbonzini@redhat.com>
> > CC: Laszlo Ersek <lersek@redhat.com>
> > Signed-off-by: Amit Shah <amit.shah@redhat.com>
> > ---
> >  hw/kvm/clock.c |   21 +++++++++++----------
> >  1 files changed, 11 insertions(+), 10 deletions(-)
> > 
> > diff --git a/hw/kvm/clock.c b/hw/kvm/clock.c
> > index 824b978..f3427eb 100644
> > --- a/hw/kvm/clock.c
> > +++ b/hw/kvm/clock.c
> > @@ -71,18 +71,19 @@ static void kvmclock_vm_state_change(void *opaque, int running,
> >  
> >      if (running) {
> >          s->clock_valid = false;
> > +        return;
> > +    }
> >  
> > -        if (!cap_clock_ctrl) {
> > -            return;
> > -        }
> > -        for (penv = first_cpu; penv != NULL; penv = penv->next_cpu) {
> > -            ret = kvm_vcpu_ioctl(penv, KVM_KVMCLOCK_CTRL, 0);
> > -            if (ret) {
> > -                if (ret != -EINVAL) {
> > -                    fprintf(stderr, "%s: %s\n", __func__, strerror(-ret));
> > -                }
> > -                return;
> > +    if (!cap_clock_ctrl) {
> > +        return;
> > +    }
> > +    for (penv = first_cpu; penv != NULL; penv = penv->next_cpu) {
> > +        ret = kvm_vcpu_ioctl(penv, KVM_KVMCLOCK_CTRL, 0);
> > +        if (ret) {
> > +            if (ret != -EINVAL) {
> > +                fprintf(stderr, "%s: %s\n", __func__, strerror(-ret));
> >              }
> > +            return;
> >          }
> >      }
> >  }
> > -- 
> > 1.7.7.6
> 
> ACK
> 
> Avi, please merge through uq/master.

NACK, guest should be notified when the VM is starting, not
when stopping.