KVM: MMU: Expose the LA57 feature to VM.

This patch exposes 5 level page table feature to the VM.
At the same time, the canonical virtual address checking is
extended to support both 48-bits and 57-bits address width.

Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bdef532..b4d4f51 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -85,8 +85,8 @@
                          | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_MCE     \
                          | X86_CR4_PGE | X86_CR4_PCE | X86_CR4_OSFXSR | X86_CR4_PCIDE \
                          | X86_CR4_OSXSAVE | X86_CR4_SMEP | X86_CR4_FSGSBASE \
-                         | X86_CR4_OSXMMEXCPT | X86_CR4_VMXE | X86_CR4_SMAP \
-                         | X86_CR4_PKE))
+                         | X86_CR4_OSXMMEXCPT | X86_CR4_LA57 | X86_CR4_VMXE \
+                         | X86_CR4_SMAP | X86_CR4_PKE))
 
 #define CR8_RESERVED_BITS (~(unsigned long)X86_CR8_TPR)
 
@@ -1300,20 +1300,6 @@ static inline void kvm_inject_gp(struct kvm_vcpu *vcpu, u32 error_code)
        kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
 }
 
-static inline u64 get_canonical(u64 la)
-{
-       return ((int64_t)la << 16) >> 16;
-}
-
-static inline bool is_noncanonical_address(u64 la)
-{
-#ifdef CONFIG_X86_64
-       return get_canonical(la) != la;
-#else
-       return false;
-#endif
-}
-
 #define TSS_IOPB_BASE_OFFSET 0x66
 #define TSS_BASE_SIZE 0x68
 #define TSS_IOPB_SIZE (65536 / 8)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index f8f18f4..1cea3ff 100644 (file)
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -126,13 +126,16 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu)
                best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
 
        /*
-        * The existing code assumes virtual address is 48-bit in the canonical
-        * address checks; exit if it is ever changed.
+        * The existing code assumes virtual address is 48-bit or 57-bit in the
+        * canonical address checks; exit if it is ever changed.
         */
        best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0);
-       if (best && ((best->eax & 0xff00) >> 8) != 48 &&
-               ((best->eax & 0xff00) >> 8) != 0)
-               return -EINVAL;
+       if (best) {
+               int vaddr_bits = (best->eax & 0xff00) >> 8;
+
+               if (vaddr_bits != 48 && vaddr_bits != 57 && vaddr_bits != 0)
+                       return -EINVAL;
+       }
 
        /* Update physical-address width */
        vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
@@ -384,7 +387,8 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
 
        /* cpuid 7.0.ecx*/
        const u32 kvm_cpuid_7_0_ecx_x86_features =
-               F(AVX512VBMI) | F(PKU) | 0 /*OSPKE*/ | F(AVX512_VPOPCNTDQ);
+               F(AVX512VBMI) | F(LA57) | F(PKU) |
+               0 /*OSPKE*/ | F(AVX512_VPOPCNTDQ);
 
        /* cpuid 7.0.edx*/
        const u32 kvm_cpuid_7_0_edx_x86_features =

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index a89b595..16bf665 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -689,16 +689,18 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
        ulong la;
        u32 lim;
        u16 sel;
+       u8  va_bits;
 
        la = seg_base(ctxt, addr.seg) + addr.ea;
        *max_size = 0;
        switch (mode) {
        case X86EMUL_MODE_PROT64:
                *linear = la;
-               if (is_noncanonical_address(la))
+               va_bits = ctxt_virt_addr_bits(ctxt);
+               if (get_canonical(la, va_bits) != la)
                        goto bad;
 
-               *max_size = min_t(u64, ~0u, (1ull << 48) - la);
+               *max_size = min_t(u64, ~0u, (1ull << va_bits) - la);
                if (size > *max_size)
                        goto bad;
                break;
@@ -1749,8 +1751,8 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
                                sizeof(base3), &ctxt->exception);
                if (ret != X86EMUL_CONTINUE)
                        return ret;
-               if (is_noncanonical_address(get_desc_base(&seg_desc) |
-                                            ((u64)base3 << 32)))
+               if (emul_is_noncanonical_address(get_desc_base(&seg_desc) |
+                               ((u64)base3 << 32), ctxt))
                        return emulate_gp(ctxt, 0);
        }
 load:
@@ -2841,8 +2843,8 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt)
                ss_sel = cs_sel + 8;
                cs.d = 0;
                cs.l = 1;
-               if (is_noncanonical_address(rcx) ||
-                   is_noncanonical_address(rdx))
+               if (emul_is_noncanonical_address(rcx, ctxt) ||
+                   emul_is_noncanonical_address(rdx, ctxt))
                        return emulate_gp(ctxt, 0);
                break;
        }
@@ -3757,7 +3759,7 @@ static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt)
        if (rc != X86EMUL_CONTINUE)
                return rc;
        if (ctxt->mode == X86EMUL_MODE_PROT64 &&
-           is_noncanonical_address(desc_ptr.address))
+           emul_is_noncanonical_address(desc_ptr.address, ctxt))
                return emulate_gp(ctxt, 0);
        if (lgdt)
                ctxt->ops->set_gdt(ctxt, &desc_ptr);

diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 762cdf2..0052317 100644 (file)
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -4,7 +4,7 @@
 #define KVM_POSSIBLE_CR0_GUEST_BITS X86_CR0_TS
 #define KVM_POSSIBLE_CR4_GUEST_BITS                              \
        (X86_CR4_PVI | X86_CR4_DE | X86_CR4_PCE | X86_CR4_OSFXSR  \
-        | X86_CR4_OSXMMEXCPT | X86_CR4_PGE)
+        | X86_CR4_OSXMMEXCPT | X86_CR4_LA57 | X86_CR4_PGE)
 
 static inline unsigned long kvm_register_read(struct kvm_vcpu *vcpu,
                                              enum kvm_reg reg)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index f234bc8..31ab27e 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -122,7 +122,7 @@ module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
        (KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST | X86_CR0_PG | X86_CR0_PE)
 #define KVM_CR4_GUEST_OWNED_BITS                                     \
        (X86_CR4_PVI | X86_CR4_DE | X86_CR4_PCE | X86_CR4_OSFXSR      \
-        | X86_CR4_OSXMMEXCPT | X86_CR4_TSD)
+        | X86_CR4_OSXMMEXCPT | X86_CR4_LA57 | X86_CR4_TSD)
 
 #define KVM_PMODE_VM_CR4_ALWAYS_ON (X86_CR4_PAE | X86_CR4_VMXE)
 #define KVM_RMODE_VM_CR4_ALWAYS_ON (X86_CR4_VME | X86_CR4_PAE | X86_CR4_VMXE)
@@ -3374,7 +3374,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
                    (!msr_info->host_initiated &&
                     !guest_cpuid_has(vcpu, X86_FEATURE_MPX)))
                        return 1;
-               if (is_noncanonical_address(data & PAGE_MASK) ||
+               if (is_noncanonical_address(data & PAGE_MASK, vcpu) ||
                    (data & MSR_IA32_BNDCFGS_RSVD))
                        return 1;
                vmcs_write64(GUEST_BNDCFGS, data);
@@ -7143,7 +7143,7 @@ static int get_vmx_mem_address(struct kvm_vcpu *vcpu,
                 * non-canonical form. This is the only check on the memory
                 * destination for long mode!
                 */
-               exn = is_noncanonical_address(*ret);
+               exn = is_noncanonical_address(*ret, vcpu);
        } else if (is_protmode(vcpu)) {
                /* Protected mode: apply checks for segment validity in the
                 * following order:
@@ -7948,7 +7948,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
 
        switch (type) {
        case VMX_VPID_EXTENT_INDIVIDUAL_ADDR:
-               if (is_noncanonical_address(operand.gla)) {
+               if (is_noncanonical_address(operand.gla, vcpu)) {
                        nested_vmx_failValid(vcpu,
                                VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
                        return kvm_skip_emulated_instruction(vcpu);

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 79f5889..80eceb7 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -769,6 +769,9 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
        if (!guest_cpuid_has(vcpu, X86_FEATURE_PKU) && (cr4 & X86_CR4_PKE))
                return 1;
 
+       if (!guest_cpuid_has(vcpu, X86_FEATURE_LA57) && (cr4 & X86_CR4_LA57))
+               return 1;
+
        if (is_long_mode(vcpu)) {
                if (!(cr4 & X86_CR4_PAE))
                        return 1;
@@ -1074,7 +1077,7 @@ int kvm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
        case MSR_KERNEL_GS_BASE:
        case MSR_CSTAR:
        case MSR_LSTAR:
-               if (is_noncanonical_address(msr->data))
+               if (is_noncanonical_address(msr->data, vcpu))
                        return 1;
                break;
        case MSR_IA32_SYSENTER_EIP:
@@ -1091,7 +1094,7 @@ int kvm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
                 * value, and that something deterministic happens if the guest
                 * invokes 64-bit SYSENTER.
                 */
-               msr->data = get_canonical(msr->data);
+               msr->data = get_canonical(msr->data, vcpu_virt_addr_bits(vcpu));
        }
        return kvm_x86_ops->set_msr(vcpu, msr);
 }

diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 69de8bf..de1abf4 100644 (file)
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -97,6 +97,40 @@ static inline u32 bit(int bitno)
        return 1 << (bitno & 31);
 }
 
+static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu)
+{
+       return kvm_read_cr4_bits(vcpu, X86_CR4_LA57) ? 57 : 48;
+}
+
+static inline u8 ctxt_virt_addr_bits(struct x86_emulate_ctxt *ctxt)
+{
+       return (ctxt->ops->get_cr(ctxt, 4) & X86_CR4_LA57) ? 57 : 48;
+}
+
+static inline u64 get_canonical(u64 la, u8 vaddr_bits)
+{
+       return ((int64_t)la << (64 - vaddr_bits)) >> (64 - vaddr_bits);
+}
+
+static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_X86_64
+       return get_canonical(la, vcpu_virt_addr_bits(vcpu)) != la;
+#else
+       return false;
+#endif
+}
+
+static inline bool emul_is_noncanonical_address(u64 la,
+                                               struct x86_emulate_ctxt *ctxt)
+{
+#ifdef CONFIG_X86_64
+       return get_canonical(la, ctxt_virt_addr_bits(ctxt)) != la;
+#else
+       return false;
+#endif
+}
+
 static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu,
                                        gva_t gva, gfn_t gfn, unsigned access)
 {