On 1 February 2018 at 14:23, Paolo Bonzini <pbonz...@redhat.com> wrote: > On 01/02/2018 08:47, Gonglei wrote: >> diff --git a/hw/timer/mc146818rtc.c b/hw/timer/mc146818rtc.c >> index 35a05a6..d9d99c5 100644 >> --- a/hw/timer/mc146818rtc.c >> +++ b/hw/timer/mc146818rtc.c >> @@ -986,6 +986,7 @@ static void rtc_realizefn(DeviceState *dev, Error **errp) >> qemu_register_suspend_notifier(&s->suspend_notifier); >> >> memory_region_init_io(&s->io, OBJECT(s), &cmos_ops, s, "rtc", 2); >> + memory_region_clear_global_locking(&s->io); >> isa_register_ioport(isadev, &s->io, base); >> >> qdev_set_legacy_instance_id(dev, base, 3); >> > > This is not enough, you need to add a new lock or something like that. > Otherwise two vCPUs can access the RTC together and make a mess.
Do you also need to do something to take the global lock before raising the outbound IRQ line (since it might be connected to a device that does need the global lock), or am I confused ? thanks -- PMM
