Re: [RFC PATCH v5 1/1] s390x: sigp: Reorder the SIGP STOP code

[Thomas Huth]

On 18/01/2022 14.34, David Hildenbrand wrote:
> On 13.12.21 22:09, Eric Farman wrote:
> > Let's wait to mark the VCPU STOPPED until the possible
> > STORE STATUS operation is completed, so that we know the
> > CPU is fully stopped and done doing anything. (When we
> > also clear the possible sigp_order field for STOP orders.)
> >
> > Suggested-by: David Hildenbrand <david@redhat.com>
> > Signed-off-by: Eric Farman <farman@linux.ibm.com>
> > ---
> >   target/s390x/sigp.c | 12 ++++++++----
> >   1 file changed, 8 insertions(+), 4 deletions(-)
> >
> > diff --git a/target/s390x/sigp.c b/target/s390x/sigp.c
> > index 51c727834c..9dd977349a 100644
> > --- a/target/s390x/sigp.c
> > +++ b/target/s390x/sigp.c
> > @@ -139,7 +139,7 @@ static void sigp_stop_and_store_status(CPUState *cs, 
> > run_on_cpu_data arg)
> >       case S390_CPU_STATE_OPERATING:
> >           cpu->env.sigp_order = SIGP_STOP_STORE_STATUS;
> >           cpu_inject_stop(cpu);
> > -        /* store will be performed in do_stop_interrup() */
> > +        /* store will be performed in do_stop_interrupt() */
> >           break;
> >       case S390_CPU_STATE_STOPPED:
> >           /* already stopped, just store the status */
> > @@ -479,13 +479,17 @@ void do_stop_interrupt(CPUS390XState *env)
> >   {
> >       S390CPU *cpu = env_archcpu(env);
> >   
> > -    if (s390_cpu_set_state(S390_CPU_STATE_STOPPED, cpu) == 0) {
> > -        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
> > -    }
> > +    /*
> > +     * Complete the STOP operation before exposing the CPU as
> > +     * STOPPED to the system.
> > +     */
> >       if (cpu->env.sigp_order == SIGP_STOP_STORE_STATUS) {
> >           s390_store_status(cpu, S390_STORE_STATUS_DEF_ADDR, true);
> >       }
> >       env->sigp_order = 0;
> > +    if (s390_cpu_set_state(S390_CPU_STATE_STOPPED, cpu) == 0) {
> > +        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
> > +    }
> >       env->pending_int &= ~INTERRUPT_STOP;
> >   }
> >   
>
> Reviewed-by: David Hildenbrand <david@redhat.com>

Thanks, queued to my s390x-next branch now:

 https://gitlab.com/thuth/qemu/-/commits/s390x-next/

 Thomas