On Wed, 26 Aug 2015 13:50:25 -0300 Eduardo Habkost <ehabkost@xxxxxxxxxx> wrote: > Current default behavior of QEMU is to silently disable features that > are not supported by the host when a CPU model is requested in the > command-line. This means that in addition to risking breaking guest ABI > by default, we are silent about it. > > I would like to enable "enforce" by default, but this can easily break > existing production systems because of the way libvirt makes assumptions > about CPU models today (this will change in the future, once QEMU > provide a proper interface for checking if a CPU model is runnable). > > But there's no reason we should be silent about it. So, change > target-i386 to enable "check" mode by default so at least we have some > warning printed to stderr (and hopefully logged somewhere) when QEMU > disables a feature that is not supported by the host system. > > Signed-off-by: Eduardo Habkost <ehabkost@xxxxxxxxxx> > --- > target-i386/cpu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/target-i386/cpu.c b/target-i386/cpu.c > index cfb8aa7..32fee00 100644 > --- a/target-i386/cpu.c > +++ b/target-i386/cpu.c > @@ -3121,7 +3121,7 @@ static Property x86_cpu_properties[] = { > DEFINE_PROP_BOOL("hv-relaxed", X86CPU, hyperv_relaxed_timing, false), > DEFINE_PROP_BOOL("hv-vapic", X86CPU, hyperv_vapic, false), > DEFINE_PROP_BOOL("hv-time", X86CPU, hyperv_time, false), > - DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, false), > + DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true), > DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false), > DEFINE_PROP_BOOL("kvm", X86CPU, expose_kvm, true), > DEFINE_PROP_UINT32("level", X86CPU, env.cpuid_level, 0), Reviewed-by: Igor Mammedov <imammedo@xxxxxxxxxx> -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list