On 05.10.2016 02:07, David Gibson wrote: > On Tue, Oct 04, 2016 at 02:55:44PM +0200, Thomas Huth wrote: >> A couple of distributors are compiling their distributions >> with "-mcpu=power8" for ppc64le these days, so the user sooner >> or later runs into a crash there when not explicitely specifying >> the "-cpu POWER8" option to QEMU. Due to this reason, the linux-user >> target already switched to POWER8 by default a while ago (see commit >> de3f1b98410e0d5b406a0df3a48547b559d18602). Since the softmmu target >> of course has the same problem, we should switch there to POWER8 >> by default for the newer machine types, too. >> >> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1357808 >> Signed-off-by: Thomas Huth > > Sounds good, one detail.. > >> --- >> Note: This patch should be applied on top of David's ppc-for-2.8 >> tree, since the pseries-2.8 machine has just been added there >> recently. >> >> hw/ppc/spapr.c | 11 ++++++++++- >> include/hw/ppc/spapr.h | 1 + >> 2 files changed, 11 insertions(+), 1 deletion(-) >> >> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c >> index 63b6a0d..799bcff 100644 >> --- a/hw/ppc/spapr.c >> +++ b/hw/ppc/spapr.c >> @@ -1775,7 +1775,13 @@ static void ppc_spapr_init(MachineState *machine) >> >> /* init CPUs */ >> if (machine->cpu_model == NULL) { >> - machine->cpu_model = kvm_enabled() ? "host" : "POWER7"; >> + if (kvm_enabled()) { >> + machine->cpu_model = "host"; >> + } else if (smc->tcg_default_cpu) { >> + machine->cpu_model = smc->tcg_default_cpu; >> + } else { >> + machine->cpu_model = "POWER8"; >> + } > > You can avoid the last if branch if you initialize tcg_default_cpu to > POWER8 in spapr_machine_class_init(). You're right, that sounds better. I'll send a v2 ... Thomas