| Message ID | 20181022165506.30332-3-vkuznets@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | i386/kvm: add support for Hyper-V Enlightened VMCS | expand |
On Mon, Oct 22, 2018 at 06:55:06PM +0200, Vitaly Kuznetsov wrote: > Adds a new CPU flag to enable the Enlightened VMCS KVM feature. > QEMU enables KVM_CAP_HYPERV_ENLIGHTENED_VMCS and gets back the > version to be advertised in lower 16 bits of CPUID.0x4000000A:EAX. > > Suggested-by: Ladi Prosek <lprosek@redhat.com> > Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> > --- > Changes since v1: > - Throw away HV_CPUID_MIN_NESTED. > - Create zeroed 0x40000006-0x40000009 CPUID leaves. > --- > target/i386/cpu.c | 1 + > target/i386/cpu.h | 1 + > target/i386/hyperv-proto.h | 2 ++ > target/i386/kvm.c | 30 ++++++++++++++++++++++++++++-- > 4 files changed, 32 insertions(+), 2 deletions(-) Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Roman Kagan <rkagan@virtuozzo.com> writes: > On Mon, Oct 22, 2018 at 06:55:06PM +0200, Vitaly Kuznetsov wrote: >> Adds a new CPU flag to enable the Enlightened VMCS KVM feature. >> QEMU enables KVM_CAP_HYPERV_ENLIGHTENED_VMCS and gets back the >> version to be advertised in lower 16 bits of CPUID.0x4000000A:EAX. >> >> Suggested-by: Ladi Prosek <lprosek@redhat.com> >> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> >> --- >> Changes since v1: >> - Throw away HV_CPUID_MIN_NESTED. >> - Create zeroed 0x40000006-0x40000009 CPUID leaves. >> --- >> target/i386/cpu.c | 1 + >> target/i386/cpu.h | 1 + >> target/i386/hyperv-proto.h | 2 ++ >> target/i386/kvm.c | 30 ++++++++++++++++++++++++++++-- >> 4 files changed, 32 insertions(+), 2 deletions(-) > > Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> With soft freeze date being today, would it still be possible to squeeze this one in? Thanks!
On 30/10/2018 18:38, Vitaly Kuznetsov wrote: > Roman Kagan <rkagan@virtuozzo.com> writes: > >> On Mon, Oct 22, 2018 at 06:55:06PM +0200, Vitaly Kuznetsov wrote: >>> Adds a new CPU flag to enable the Enlightened VMCS KVM feature. >>> QEMU enables KVM_CAP_HYPERV_ENLIGHTENED_VMCS and gets back the >>> version to be advertised in lower 16 bits of CPUID.0x4000000A:EAX. >>> >>> Suggested-by: Ladi Prosek <lprosek@redhat.com> >>> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> >>> --- >>> Changes since v1: >>> - Throw away HV_CPUID_MIN_NESTED. >>> - Create zeroed 0x40000006-0x40000009 CPUID leaves. >>> --- >>> target/i386/cpu.c | 1 + >>> target/i386/cpu.h | 1 + >>> target/i386/hyperv-proto.h | 2 ++ >>> target/i386/kvm.c | 30 ++++++++++++++++++++++++++++-- >>> 4 files changed, 32 insertions(+), 2 deletions(-) >> >> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> > > With soft freeze date being today, would it still be possible to squeeze > this one in? Yes, I'm going to send a pull request in a matter of minutes. I'm not sure if technically it should have been sent yesterday, but I suppose we can have some leeway because of the conference last week. Paolo
diff --git a/target/i386/cpu.c b/target/i386/cpu.c index c88876dfe3..5c0e84fb99 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -5564,6 +5564,7 @@ static Property x86_cpu_properties[] = { DEFINE_PROP_BOOL("hv-frequencies", X86CPU, hyperv_frequencies, false), DEFINE_PROP_BOOL("hv-reenlightenment", X86CPU, hyperv_reenlightenment, false), DEFINE_PROP_BOOL("hv-tlbflush", X86CPU, hyperv_tlbflush, false), + DEFINE_PROP_BOOL("hv-evmcs", X86CPU, hyperv_evmcs, 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), diff --git a/target/i386/cpu.h b/target/i386/cpu.h index 730c06f80a..013d953b57 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1382,6 +1382,7 @@ struct X86CPU { bool hyperv_frequencies; bool hyperv_reenlightenment; bool hyperv_tlbflush; + bool hyperv_evmcs; bool check_cpuid; bool enforce_cpuid; bool expose_kvm; diff --git a/target/i386/hyperv-proto.h b/target/i386/hyperv-proto.h index d6d5a79293..1e6800ba43 100644 --- a/target/i386/hyperv-proto.h +++ b/target/i386/hyperv-proto.h @@ -18,6 +18,7 @@ #define HV_CPUID_FEATURES 0x40000003 #define HV_CPUID_ENLIGHTMENT_INFO 0x40000004 #define HV_CPUID_IMPLEMENT_LIMITS 0x40000005 +#define HV_CPUID_NESTED_FEATURES 0x4000000A #define HV_CPUID_MIN 0x40000005 #define HV_CPUID_MAX 0x4000ffff #define HV_HYPERVISOR_PRESENT_BIT 0x80000000 @@ -59,6 +60,7 @@ #define HV_SYSTEM_RESET_RECOMMENDED (1u << 4) #define HV_RELAXED_TIMING_RECOMMENDED (1u << 5) #define HV_EX_PROCESSOR_MASKS_RECOMMENDED (1u << 11) +#define HV_ENLIGHTENED_VMCS_RECOMMENDED (1u << 14) /* * Basic virtualized MSRs diff --git a/target/i386/kvm.c b/target/i386/kvm.c index a46ad102d8..6f10abcf6f 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -798,6 +798,7 @@ int kvm_arch_init_vcpu(CPUState *cs) uint32_t unused; struct kvm_cpuid_entry2 *c; uint32_t signature[3]; + uint16_t evmcs_version; int kvm_base = KVM_CPUID_SIGNATURE; int r; Error *local_err = NULL; @@ -841,7 +842,8 @@ int kvm_arch_init_vcpu(CPUState *cs) memset(signature, 0, 12); memcpy(signature, cpu->hyperv_vendor_id, len); } - c->eax = HV_CPUID_MIN; + c->eax = cpu->hyperv_evmcs ? + HV_CPUID_NESTED_FEATURES : HV_CPUID_IMPLEMENT_LIMITS; c->ebx = signature[0]; c->ecx = signature[1]; c->edx = signature[2]; @@ -888,7 +890,16 @@ int kvm_arch_init_vcpu(CPUState *cs) c->eax |= HV_REMOTE_TLB_FLUSH_RECOMMENDED; c->eax |= HV_EX_PROCESSOR_MASKS_RECOMMENDED; } - + if (cpu->hyperv_evmcs) { + if (kvm_vcpu_enable_cap(cs, KVM_CAP_HYPERV_ENLIGHTENED_VMCS, 0, + (uintptr_t)&evmcs_version)) { + fprintf(stderr, "Hyper-V Enlightened VMCS " + "(requested by 'hv-evmcs' cpu flag) " + "is not supported by kernel\n"); + return -ENOSYS; + } + c->eax |= HV_ENLIGHTENED_VMCS_RECOMMENDED; + } c->ebx = cpu->hyperv_spinlock_attempts; c = &cpuid_data.entries[cpuid_i++]; @@ -899,6 +910,21 @@ int kvm_arch_init_vcpu(CPUState *cs) kvm_base = KVM_CPUID_SIGNATURE_NEXT; has_msr_hv_hypercall = true; + + if (cpu->hyperv_evmcs) { + __u32 function; + + /* Create zeroed 0x40000006..0x40000009 leaves */ + for (function = HV_CPUID_IMPLEMENT_LIMITS + 1; + function < HV_CPUID_NESTED_FEATURES; function++) { + c = &cpuid_data.entries[cpuid_i++]; + c->function = function; + } + + c = &cpuid_data.entries[cpuid_i++]; + c->function = HV_CPUID_NESTED_FEATURES; + c->eax = evmcs_version; + } } if (cpu->expose_kvm) {
Adds a new CPU flag to enable the Enlightened VMCS KVM feature. QEMU enables KVM_CAP_HYPERV_ENLIGHTENED_VMCS and gets back the version to be advertised in lower 16 bits of CPUID.0x4000000A:EAX. Suggested-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- Changes since v1: - Throw away HV_CPUID_MIN_NESTED. - Create zeroed 0x40000006-0x40000009 CPUID leaves. --- target/i386/cpu.c | 1 + target/i386/cpu.h | 1 + target/i386/hyperv-proto.h | 2 ++ target/i386/kvm.c | 30 ++++++++++++++++++++++++++++-- 4 files changed, 32 insertions(+), 2 deletions(-)