On 04/06/2018 11:35 AM, David Hildenbrand wrote: > Manually having to use cpu_synchronize_state() is error prone. And as > Christian Borntraeger discovered, e.g. handle_diag() is currently > missing a cpu_synchronize_state(), as decode_basedisp_s() uses a > general purpose register value internally. > > So let's do an overall cpu_synchronize_state(), which fixes at least the > one mentioned BUG. We will clean up the superfluous cpu_synchronize_state() > calls later. > > We now also call it (although maybe not neded) for > - KVM_EXIT_S390_RESET -> s390_reipl_request() > - KVM_EXIT_DEBUG -> kvm_arch_handle_debug_exit() > - unmanagable/unimplemented intercepts > - ICPT_CPU_STOP -> do_stop_interrupt() -> cpu gets halted > - Scenarios where we inject an operation exception > - handle_stsi() > > I don't think any of these are performance critical. Especially as we > have all information directly contained in kvm_run, there are no > additional IOCTLs to issue on modern kernels. > > Signed-off-by: David Hildenbrand <da...@redhat.com>
Acked-by: Christian Borntraeger <borntrae...@de.ibm.com> ok for 2.12. > --- > target/s390x/kvm.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c > index f570896dc1..fb59d92def 100644 > --- a/target/s390x/kvm.c > +++ b/target/s390x/kvm.c > @@ -1778,6 +1778,8 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run > *run) > > qemu_mutex_lock_iothread(); > > + cpu_synchronize_state(cs); > + > switch (run->exit_reason) { > case KVM_EXIT_S390_SIEIC: > ret = handle_intercept(cpu); >