diff options
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index c42613cfb5ba..739be5da3bca 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -765,7 +765,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) edx.split.num_counters_fixed = min(cap.num_counters_fixed, MAX_FIXED_COUNTERS); edx.split.bit_width_fixed = cap.bit_width_fixed; - edx.split.anythread_deprecated = 1; + if (cap.version) + edx.split.anythread_deprecated = 1; edx.split.reserved1 = 0; edx.split.reserved2 = 0; @@ -940,8 +941,21 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U); unsigned phys_as = entry->eax & 0xff; - if (!g_phys_as) + /* + * If TDP (NPT) is disabled use the adjusted host MAXPHYADDR as + * the guest operates in the same PA space as the host, i.e. + * reductions in MAXPHYADDR for memory encryption affect shadow + * paging, too. + * + * If TDP is enabled but an explicit guest MAXPHYADDR is not + * provided, use the raw bare metal MAXPHYADDR as reductions to + * the HPAs do not affect GPAs. + */ + if (!tdp_enabled) + g_phys_as = boot_cpu_data.x86_phys_bits; + else if (!g_phys_as) g_phys_as = phys_as; + entry->eax = g_phys_as | (virt_as << 8); entry->edx = 0; cpuid_entry_override(entry, CPUID_8000_0008_EBX); @@ -964,12 +978,18 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) case 0x8000001a: case 0x8000001e: break; - /* Support memory encryption cpuid if host supports it */ case 0x8000001F: - if (!kvm_cpu_cap_has(X86_FEATURE_SEV)) + if (!kvm_cpu_cap_has(X86_FEATURE_SEV)) { entry->eax = entry->ebx = entry->ecx = entry->edx = 0; - else + } else { cpuid_entry_override(entry, CPUID_8000_001F_EAX); + + /* + * Enumerate '0' for "PA bits reduction", the adjusted + * MAXPHYADDR is enumerated directly (see 0x80000008). + */ + entry->ebx &= ~GENMASK(11, 6); + } break; /*Add support for Centaur's CPUID instruction*/ case 0xC0000000: |