Changes since v5: - Temporary drop 'hv-default' feature as it is causing some controversy. The rest of the patchset is valuable on its own. - Add 3 additiona fixes: i386: kill off hv_cpuid_check_and_set() [Igor's suggestion] i386: HV_HYPERCALL_AVAILABLE privilege bit is always needed i386: Hyper-V SynIC requires POST_MESSAGES/SIGNAL_EVENTS priviliges
The last two patches are inspired by 'Fine-grained access check to Hyper-V hypercalls and MSRs' work for KVM: https://lore.kernel.org/kvm/20210419160127.192712-1-vkuzn...@redhat.com/ Original description: Upper layer tools like libvirt want to figure out which Hyper-V features are supported by the underlying stack (QEMU/KVM) but currently they are unable to do so. We have a nice 'hv_passthrough' CPU flag supported by QEMU but it has no effect on e.g. QMP's query-cpu-model-expansion type=full model={"name":"host","props":{"hv-passthrough":true}} command as we parse Hyper-V features after creating KVM vCPUs and not at feature expansion time. To support the use-case we first need to make KVM_GET_SUPPORTED_HV_CPUID ioctl a system-wide ioctl as the existing vCPU version can't be used that early. This is what KVM part does. With that done, we can make early Hyper-V feature expansion (this series). Vitaly Kuznetsov (19): i386: keep hyperv_vendor string up-to-date i386: invert hyperv_spinlock_attempts setting logic with hv_passthrough i386: always fill Hyper-V CPUID feature leaves from X86CPU data i386: stop using env->features[] for filling Hyper-V CPUIDs i386: introduce hyperv_feature_supported() i386: introduce hv_cpuid_get_host() i386: drop FEAT_HYPERV feature leaves i386: introduce hv_cpuid_cache i386: split hyperv_handle_properties() into hyperv_expand_features()/hyperv_fill_cpuids() i386: move eVMCS enablement to hyperv_init_vcpu() i386: switch hyperv_expand_features() to using error_setg() i386: adjust the expected KVM_GET_SUPPORTED_HV_CPUID array size i386: prefer system KVM_GET_SUPPORTED_HV_CPUID ioctl over vCPU's one i386: use global kvm_state in hyperv_enabled() check i386: expand Hyper-V features during CPU feature expansion time i386: kill off hv_cpuid_check_and_set() i386: HV_HYPERCALL_AVAILABLE privilege bit is always needed i386: Hyper-V SynIC requires POST_MESSAGES/SIGNAL_EVENTS priviliges qtest/hyperv: Introduce a simple hyper-v test MAINTAINERS | 1 + target/i386/cpu.c | 113 +------- target/i386/cpu.h | 6 +- target/i386/kvm/hyperv-proto.h | 6 + target/i386/kvm/kvm-stub.c | 5 + target/i386/kvm/kvm.c | 514 +++++++++++++++++---------------- target/i386/kvm/kvm_i386.h | 1 + tests/qtest/hyperv-test.c | 225 +++++++++++++++ tests/qtest/meson.build | 3 +- 9 files changed, 526 insertions(+), 348 deletions(-) create mode 100644 tests/qtest/hyperv-test.c -- 2.30.2
