| Message ID | 51725754.2010304@web.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Il 20/04/2013 10:52, Jan Kiszka ha scritto: > As we may emulate the loading of EFER on VM-entry and VM-exit, implement > the checks that VMX performs on the guest and host values on vmlaunch/ > vmresume. Factor out kvm_valid_efer for this purpose which checks for > set reserved bits. > > Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> > --- > > Changes in v2: > - refactored if clauses as requested by Paolo > - fixed typo in comment found my Marcelo > > arch/x86/include/asm/kvm_host.h | 1 + > arch/x86/kvm/vmx.c | 40 +++++++++++++++++++++++++++++++++++++++ > arch/x86/kvm/x86.c | 29 ++++++++++++++++++--------- > 3 files changed, 60 insertions(+), 10 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 599f98b..18635ae 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -809,6 +809,7 @@ static inline int emulate_instruction(struct kvm_vcpu *vcpu, > } > > void kvm_enable_efer_bits(u64); > +bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer); > int kvm_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *data); > int kvm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr); > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 19aebc7..e3b951f 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -7327,6 +7327,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) > struct vcpu_vmx *vmx = to_vmx(vcpu); > int cpu; > struct loaded_vmcs *vmcs02; > + bool ia32e; > > if (!nested_vmx_check_permission(vcpu) || > !nested_vmx_check_vmcs12(vcpu)) > @@ -7415,6 +7416,45 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) > } > > /* > + * If the “load IA32_EFER” VM-entry control is 1, the following checks > + * are performed on the field for the IA32_EFER MSR: > + * - Bits reserved in the IA32_EFER MSR must be 0. > + * - Bit 10 (corresponding to IA32_EFER.LMA) must equal the value of > + * the IA-32e mode guest VM-exit control. It must also be identical > + * to bit 8 (LME) if bit 31 in the CR0 field (corresponding to > + * CR0.PG) is 1. > + */ > + if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_EFER) { > + ia32e = (vmcs12->vm_entry_controls & VM_ENTRY_IA32E_MODE) != 0; > + if (!kvm_valid_efer(vcpu, vmcs12->guest_ia32_efer) || > + ia32e != !!(vmcs12->guest_ia32_efer & EFER_LMA) || > + ((vmcs12->guest_cr0 & X86_CR0_PG) && > + ia32e != !!(vmcs12->guest_ia32_efer & EFER_LME))) { > + nested_vmx_entry_failure(vcpu, vmcs12, > + EXIT_REASON_INVALID_STATE, ENTRY_FAIL_DEFAULT); > + return 1; > + } > + } > + > + /* > + * If the load IA32_EFER VM-exit control is 1, bits reserved in the > + * IA32_EFER MSR must be 0 in the field for that register. In addition, > + * the values of the LMA and LME bits in the field must each be that of > + * the host address-space size VM-exit control. > + */ > + if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_EFER) { > + ia32e = (vmcs12->vm_exit_controls & > + VM_EXIT_HOST_ADDR_SPACE_SIZE) != 0; > + if (!kvm_valid_efer(vcpu, vmcs12->host_ia32_efer) || > + ia32e != !!(vmcs12->host_ia32_efer & EFER_LMA) || > + ia32e != !!(vmcs12->host_ia32_efer & EFER_LME)) { > + nested_vmx_entry_failure(vcpu, vmcs12, > + EXIT_REASON_INVALID_STATE, ENTRY_FAIL_DEFAULT); > + return 1; > + } > + } Looks good, difficult to do better with C's operator precedence rules. Paolo > + /* > * We're finally done with prerequisite checking, and can start with > * the nested entry. > */ > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 50e2e10..482784d 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -845,23 +845,17 @@ static const u32 emulated_msrs[] = { > MSR_IA32_MCG_CTL, > }; > > -static int set_efer(struct kvm_vcpu *vcpu, u64 efer) > +bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer) > { > - u64 old_efer = vcpu->arch.efer; > - > if (efer & efer_reserved_bits) > - return 1; > - > - if (is_paging(vcpu) > - && (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME)) > - return 1; > + return false; > > if (efer & EFER_FFXSR) { > struct kvm_cpuid_entry2 *feat; > > feat = kvm_find_cpuid_entry(vcpu, 0x80000001, 0); > if (!feat || !(feat->edx & bit(X86_FEATURE_FXSR_OPT))) > - return 1; > + return false; > } > > if (efer & EFER_SVME) { > @@ -869,9 +863,24 @@ static int set_efer(struct kvm_vcpu *vcpu, u64 efer) > > feat = kvm_find_cpuid_entry(vcpu, 0x80000001, 0); > if (!feat || !(feat->ecx & bit(X86_FEATURE_SVM))) > - return 1; > + return false; > } > > + return true; > +} > +EXPORT_SYMBOL_GPL(kvm_valid_efer); > + > +static int set_efer(struct kvm_vcpu *vcpu, u64 efer) > +{ > + u64 old_efer = vcpu->arch.efer; > + > + if (!kvm_valid_efer(vcpu, efer)) > + return 1; > + > + if (is_paging(vcpu) > + && (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME)) > + return 1; > + > efer &= ~EFER_LMA; > efer |= vcpu->arch.efer & EFER_LMA; > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 599f98b..18635ae 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -809,6 +809,7 @@ static inline int emulate_instruction(struct kvm_vcpu *vcpu, } void kvm_enable_efer_bits(u64); +bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer); int kvm_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *data); int kvm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr); diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 19aebc7..e3b951f 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -7327,6 +7327,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) struct vcpu_vmx *vmx = to_vmx(vcpu); int cpu; struct loaded_vmcs *vmcs02; + bool ia32e; if (!nested_vmx_check_permission(vcpu) || !nested_vmx_check_vmcs12(vcpu)) @@ -7415,6 +7416,45 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) } /* + * If the “load IA32_EFER” VM-entry control is 1, the following checks + * are performed on the field for the IA32_EFER MSR: + * - Bits reserved in the IA32_EFER MSR must be 0. + * - Bit 10 (corresponding to IA32_EFER.LMA) must equal the value of + * the IA-32e mode guest VM-exit control. It must also be identical + * to bit 8 (LME) if bit 31 in the CR0 field (corresponding to + * CR0.PG) is 1. + */ + if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_EFER) { + ia32e = (vmcs12->vm_entry_controls & VM_ENTRY_IA32E_MODE) != 0; + if (!kvm_valid_efer(vcpu, vmcs12->guest_ia32_efer) || + ia32e != !!(vmcs12->guest_ia32_efer & EFER_LMA) || + ((vmcs12->guest_cr0 & X86_CR0_PG) && + ia32e != !!(vmcs12->guest_ia32_efer & EFER_LME))) { + nested_vmx_entry_failure(vcpu, vmcs12, + EXIT_REASON_INVALID_STATE, ENTRY_FAIL_DEFAULT); + return 1; + } + } + + /* + * If the load IA32_EFER VM-exit control is 1, bits reserved in the + * IA32_EFER MSR must be 0 in the field for that register. In addition, + * the values of the LMA and LME bits in the field must each be that of + * the host address-space size VM-exit control. + */ + if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_EFER) { + ia32e = (vmcs12->vm_exit_controls & + VM_EXIT_HOST_ADDR_SPACE_SIZE) != 0; + if (!kvm_valid_efer(vcpu, vmcs12->host_ia32_efer) || + ia32e != !!(vmcs12->host_ia32_efer & EFER_LMA) || + ia32e != !!(vmcs12->host_ia32_efer & EFER_LME)) { + nested_vmx_entry_failure(vcpu, vmcs12, + EXIT_REASON_INVALID_STATE, ENTRY_FAIL_DEFAULT); + return 1; + } + } + + /* * We're finally done with prerequisite checking, and can start with * the nested entry. */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 50e2e10..482784d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -845,23 +845,17 @@ static const u32 emulated_msrs[] = { MSR_IA32_MCG_CTL, }; -static int set_efer(struct kvm_vcpu *vcpu, u64 efer) +bool kvm_valid_efer(struct kvm_vcpu *vcpu, u64 efer) { - u64 old_efer = vcpu->arch.efer; - if (efer & efer_reserved_bits) - return 1; - - if (is_paging(vcpu) - && (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME)) - return 1; + return false; if (efer & EFER_FFXSR) { struct kvm_cpuid_entry2 *feat; feat = kvm_find_cpuid_entry(vcpu, 0x80000001, 0); if (!feat || !(feat->edx & bit(X86_FEATURE_FXSR_OPT))) - return 1; + return false; } if (efer & EFER_SVME) { @@ -869,9 +863,24 @@ static int set_efer(struct kvm_vcpu *vcpu, u64 efer) feat = kvm_find_cpuid_entry(vcpu, 0x80000001, 0); if (!feat || !(feat->ecx & bit(X86_FEATURE_SVM))) - return 1; + return false; } + return true; +} +EXPORT_SYMBOL_GPL(kvm_valid_efer); + +static int set_efer(struct kvm_vcpu *vcpu, u64 efer) +{ + u64 old_efer = vcpu->arch.efer; + + if (!kvm_valid_efer(vcpu, efer)) + return 1; + + if (is_paging(vcpu) + && (vcpu->arch.efer & EFER_LME) != (efer & EFER_LME)) + return 1; + efer &= ~EFER_LMA; efer |= vcpu->arch.efer & EFER_LMA;
As we may emulate the loading of EFER on VM-entry and VM-exit, implement the checks that VMX performs on the guest and host values on vmlaunch/ vmresume. Factor out kvm_valid_efer for this purpose which checks for set reserved bits. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> --- Changes in v2: - refactored if clauses as requested by Paolo - fixed typo in comment found my Marcelo arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/vmx.c | 40 +++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/x86.c | 29 ++++++++++++++++++--------- 3 files changed, 60 insertions(+), 10 deletions(-)