diff options
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 30 | ||||
| -rw-r--r-- | arch/x86/kvm/svm.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 13 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.h | 1 |
5 files changed, 31 insertions, 16 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index cc8b24b4d8f3..78d461be2102 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -642,15 +642,22 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) cpuid_entry_override(entry, CPUID_D_1_EAX); if (entry->eax & (F(XSAVES)|F(XSAVEC))) - entry->ebx = xstate_required_size(supported_xcr0, true); - else + entry->ebx = xstate_required_size(supported_xcr0 | supported_xss, + true); + else { + WARN_ON_ONCE(supported_xss != 0); entry->ebx = 0; - /* Saving XSS controlled state via XSAVES isn't supported. */ - entry->ecx = 0; - entry->edx = 0; + } + entry->ecx &= supported_xss; + entry->edx &= supported_xss >> 32; for (i = 2; i < 64; ++i) { - if (!(supported_xcr0 & BIT_ULL(i))) + bool s_state; + if (supported_xcr0 & BIT_ULL(i)) + s_state = false; + else if (supported_xss & BIT_ULL(i)) + s_state = true; + else continue; entry = do_host_cpuid(array, function, i); @@ -659,17 +666,16 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) /* * The supported check above should have filtered out - * invalid sub-leafs as well as sub-leafs managed by - * IA32_XSS MSR. Only XCR0-managed sub-leafs should + * invalid sub-leafs. Only valid sub-leafs should * reach this point, and they should have a non-zero - * save state size. + * save state size. Furthermore, check whether the + * processor agrees with supported_xcr0/supported_xss + * on whether this is an XCR0- or IA32_XSS-managed area. */ - if (WARN_ON_ONCE(!entry->eax || (entry->ecx & 1))) { + if (WARN_ON_ONCE(!entry->eax || (entry->ecx & 0x1) != s_state)) { --array->nent; continue; } - - entry->ecx = 0; entry->edx = 0; } break; diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index c6e9910d1149..4dca3579e740 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1371,6 +1371,8 @@ static __init void svm_set_cpu_caps(void) { kvm_set_cpu_caps(); + supported_xss = 0; + /* CPUID 0x80000001 and 0x8000000A (SVM features) */ if (nested) { kvm_cpu_cap_set(X86_FEATURE_SVM); diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index e91a84bb251c..8001070b209c 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7126,6 +7126,7 @@ static __init void vmx_set_cpu_caps(void) kvm_cpu_cap_set(X86_FEATURE_UMIP); /* CPUID 0xD.1 */ + supported_xss = 0; if (!vmx_xsaves_supported()) kvm_cpu_cap_clear(X86_FEATURE_XSAVES); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d2f1b4746903..96e897d38a63 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -190,6 +190,8 @@ u64 __read_mostly host_efer; EXPORT_SYMBOL_GPL(host_efer); static u64 __read_mostly host_xss; +u64 __read_mostly supported_xss; +EXPORT_SYMBOL_GPL(supported_xss); struct kvm_stats_debugfs_item debugfs_entries[] = { { "pf_fixed", VCPU_STAT(pf_fixed) }, @@ -2827,7 +2829,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) * IA32_XSS[bit 8]. Guests have to use RDMSR/WRMSR rather than * XSAVES/XRSTORS to save/restore PT MSRs. */ - if (data != 0) + if (data & ~supported_xss) return 1; vcpu->arch.ia32_xss = data; break; @@ -9617,10 +9619,16 @@ int kvm_arch_hardware_setup(void) rdmsrl_safe(MSR_EFER, &host_efer); + if (boot_cpu_has(X86_FEATURE_XSAVES)) + rdmsrl(MSR_IA32_XSS, host_xss); + r = kvm_x86_ops->hardware_setup(); if (r != 0) return r; + if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES)) + supported_xss = 0; + cr4_reserved_bits = kvm_host_cr4_reserved_bits(&boot_cpu_data); if (kvm_has_tsc_control) { @@ -9637,9 +9645,6 @@ int kvm_arch_hardware_setup(void) kvm_default_tsc_scaling_ratio = 1ULL << kvm_tsc_scaling_ratio_frac_bits; } - if (boot_cpu_has(X86_FEATURE_XSAVES)) - rdmsrl(MSR_IA32_XSS, host_xss); - kvm_init_msr_list(); return 0; } diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 4d890bf827e8..c1954e216b41 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -272,6 +272,7 @@ enum exit_fastpath_completion handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vc extern u64 host_xcr0; extern u64 supported_xcr0; +extern u64 supported_xss; static inline bool kvm_mpx_supported(void) { |