Expose Intel V2 Extended Topology Enumeration Leaf to guest only when host system has multiple software-visible die within each package.
Signed-off-by: Like Xu <[email protected]> --- arch/x86/kvm/cpuid.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index fd39516..9fc14f2 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -65,6 +65,16 @@ u64 kvm_supported_xcr0(void) return xcr0; } +/* We need to check if the host cpu has multi-chip packaging technology. */ +static bool kvm_supported_intel_mcp(void) +{ + u32 eax, ignored; + + cpuid_count(0x1f, 0, &eax, &ignored, &ignored, &ignored); + + return boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && (eax != 0); +} + #define F(x) bit(X86_FEATURE_##x) int kvm_update_cpuid(struct kvm_vcpu *vcpu) @@ -426,6 +436,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, switch (function) { case 0: entry->eax = min(entry->eax, (u32)(f_intel_pt ? 0x14 : 0xd)); + entry->eax = kvm_supported_intel_mcp() ? 0x1f : entry->eax; break; case 1: entry->edx &= kvm_cpuid_1_edx_x86_features; @@ -544,6 +555,8 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->edx = edx.full; break; } + /* function 0x1f has additional index. */ + case 0x1f: /* function 0xb has additional index. */ case 0xb: { int i, level_type; -- 1.8.3.1
