On Wed, 10 Feb 2021 17:40:29 +0100 Vitaly Kuznetsov <vkuzn...@redhat.com> wrote:
> Currently, we support 'hv-passthrough,hv-feature=on' enablement, this > is supposed to mean "hv-feature is mandatory, don't start without it". Add > support for 'hv-passthrough,hv-feature=off' meaning "enable everything > supported by the host except for hv-feature". > > While on it, make 'hv-passthrough' parse semantics in-line with other > options in qemu: when specified, it overrides what was previously set with > what's supported by the host. This can later be modified with 'hv-feature=on'/ > 'hv-feature=off'. > > Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com> > --- > target/i386/cpu.c | 28 +++++++++++++++++++++++++++- > target/i386/kvm/kvm.c | 4 ++++ > 2 files changed, 31 insertions(+), 1 deletion(-) > > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index e8a004c39d04..f8df2caed779 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -4725,6 +4725,29 @@ static void x86_hv_stimer_direct_set(Object *obj, bool > value, Error **errp) > x86_hv_feature_set(obj, value, HYPERV_FEAT_STIMER_DIRECT); > } > > +static bool x86_hv_passthrough_get(Object *obj, Error **errp) > +{ > + X86CPU *cpu = X86_CPU(obj); > + > + return cpu->hyperv_passthrough; > +} > + > +static void x86_hv_passthrough_set(Object *obj, bool value, Error **errp) > +{ > + X86CPU *cpu = X86_CPU(obj); > + > + cpu->hyperv_passthrough = value; > + > + /* hv-passthrough overrides everything with what's supported by the host > */ > + if (value) { > + cpu->hyperv_features = 0; > + cpu->hyperv_features_on = 0; > + cpu->hyperv_features_off = 0; why do we have _on|_off fields? > + } > + > + return; > +} > + > /* Generic getter for "feature-words" and "filtered-features" properties */ > static void x86_cpu_get_feature_words(Object *obj, Visitor *v, > const char *name, void *opaque, > @@ -7281,7 +7304,6 @@ static Property x86_cpu_properties[] = { > HYPERV_SPINLOCK_NEVER_NOTIFY), > DEFINE_PROP_ON_OFF_AUTO("hv-no-nonarch-coresharing", X86CPU, > hyperv_no_nonarch_cs, ON_OFF_AUTO_OFF), > - DEFINE_PROP_BOOL("hv-passthrough", X86CPU, hyperv_passthrough, false), > > DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true), > DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false), > @@ -7460,6 +7482,10 @@ static void x86_cpu_common_class_init(ObjectClass *oc, > void *data) > x86_hv_stimer_direct_get, > x86_hv_stimer_direct_set); > > + object_class_property_add_bool(oc, "hv-passthrough", > + x86_hv_passthrough_get, > + x86_hv_passthrough_set); > + > for (w = 0; w < FEATURE_WORDS; w++) { > int bitnr; > for (bitnr = 0; bitnr < 64; bitnr++) { > diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c > index 30013f0d7cee..fca088d4d3b5 100644 > --- a/target/i386/kvm/kvm.c > +++ b/target/i386/kvm/kvm.c > @@ -1153,6 +1153,10 @@ static int hv_cpuid_check_and_set(CPUState *cs, int > feature, Error **errp) > return 0; > } > > + if (cpu->hyperv_passthrough && (cpu->hyperv_features_off & > BIT(feature))) { > + return 0; > + } > + > deps = kvm_hyperv_properties[feature].dependencies; > while (deps) { > dep_feat = ctz64(deps);