diff options
Diffstat (limited to 'arch/x86/kvm/x86.h')
| -rw-r--r-- | arch/x86/kvm/x86.h | 48 |
1 files changed, 46 insertions, 2 deletions
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index a84c48ef5278..ec623d23d13d 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -8,6 +8,7 @@ #include <asm/pvclock.h> #include "kvm_cache_regs.h" #include "kvm_emulate.h" +#include "cpuid.h" struct kvm_caps { /* control of guest tsc rate supported? */ @@ -233,9 +234,52 @@ static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu) return kvm_is_cr4_bit_set(vcpu, X86_CR4_LA57) ? 57 : 48; } -static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu) +static inline u8 max_host_virt_addr_bits(void) { - return !__is_canonical_address(la, vcpu_virt_addr_bits(vcpu)); + return kvm_cpu_cap_has(X86_FEATURE_LA57) ? 57 : 48; +} + +/* + * x86 MSRs which contain linear addresses, x86 hidden segment bases, and + * IDT/GDT bases have static canonicality checks, the size of which depends + * only on the CPU's support for 5-level paging, rather than on the state of + * CR4.LA57. This applies to both WRMSR and to other instructions that set + * their values, e.g. SGDT. + * + * KVM passes through most of these MSRS and also doesn't intercept the + * instructions that set the hidden segment bases. + * + * Because of this, to be consistent with hardware, even if the guest doesn't + * have LA57 enabled in its CPUID, perform canonicality checks based on *host* + * support for 5 level paging. + * + * Finally, instructions which are related to MMU invalidation of a given + * linear address, also have a similar static canonical check on address. + * This allows for example to invalidate 5-level addresses of a guest from a + * host which uses 4-level paging. + */ +static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu, + unsigned int flags) +{ + if (flags & (X86EMUL_F_INVLPG | X86EMUL_F_MSR | X86EMUL_F_DT_LOAD)) + return !__is_canonical_address(la, max_host_virt_addr_bits()); + else + return !__is_canonical_address(la, vcpu_virt_addr_bits(vcpu)); +} + +static inline bool is_noncanonical_msr_address(u64 la, struct kvm_vcpu *vcpu) +{ + return is_noncanonical_address(la, vcpu, X86EMUL_F_MSR); +} + +static inline bool is_noncanonical_base_address(u64 la, struct kvm_vcpu *vcpu) +{ + return is_noncanonical_address(la, vcpu, X86EMUL_F_DT_LOAD); +} + +static inline bool is_noncanonical_invlpg_address(u64 la, struct kvm_vcpu *vcpu) +{ + return is_noncanonical_address(la, vcpu, X86EMUL_F_INVLPG); } static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu, |