2 files changed, 66 insertions, 5 deletions

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 78a4439bfdc5..86d5756dda07 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -222,6 +222,22 @@ static bool supported_xcr0_bit(unsigned bit)
 static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
                                    u32 func, u32 index, int *nent, int maxnent)
 {
+        switch (func) {
+        case 0:
+                entry->eax = 1;         /* only one leaf currently */
+                ++*nent;
+                break;
+        case 1:
+                entry->ecx = F(MOVBE);
+                ++*nent;
+                break;
+        default:
+                break;
+        }
+
+        entry->function = func;
+        entry->index = index;
+
         return 0;
 }
 
@@ -593,7 +609,7 @@ int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
                 return -EINVAL;
 
         r = -ENOMEM;
-        cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
+        cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
         if (!cpuid_entries)
                 goto out;
 
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 6c5cfe962b28..8e2a07bd8eac 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2961,6 +2961,46 @@ static int em_mov(struct x86_emulate_ctxt *ctxt)
         return X86EMUL_CONTINUE;
 }
 
+#define FFL(x) bit(X86_FEATURE_##x)
+
+static int em_movbe(struct x86_emulate_ctxt *ctxt)
+{
+        u32 ebx, ecx, edx, eax = 1;
+        u16 tmp;
+
+        /*
+         * Check MOVBE is set in the guest-visible CPUID leaf.
+         */
+        ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx);
+        if (!(ecx & FFL(MOVBE)))
+                return emulate_ud(ctxt);
+
+        switch (ctxt->op_bytes) {
+        case 2:
+                /*
+                 * From MOVBE definition: "...When the operand size is 16 bits,
+                 * the upper word of the destination register remains unchanged
+                 * ..."
+                 *
+                 * Both casting ->valptr and ->val to u16 breaks strict aliasing
+                 * rules so we have to do the operation almost per hand.
+                 */
+                tmp = (u16)ctxt->src.val;
+                ctxt->dst.val &= ~0xffffUL;
+                ctxt->dst.val |= (unsigned long)swab16(tmp);
+                break;
+        case 4:
+                ctxt->dst.val = swab32((u32)ctxt->src.val);
+                break;
+        case 8:
+                ctxt->dst.val = swab64(ctxt->src.val);
+                break;
+        default:
+                return X86EMUL_PROPAGATE_FAULT;
+        }
+        return X86EMUL_CONTINUE;
+}
+
 static int em_cr_write(struct x86_emulate_ctxt *ctxt)
 {
         if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val))
@@ -3893,11 +3933,11 @@ static const struct opcode twobyte_table[256] = {
 };
 
 static const struct gprefix three_byte_0f_38_f0 = {
-        N, N, N, N
+        I(DstReg | SrcMem | Mov, em_movbe), N, N, N
 };
 
 static const struct gprefix three_byte_0f_38_f1 = {
-        N, N, N, N
+        I(DstMem | SrcReg | Mov, em_movbe), N, N, N
 };
 
 /*
@@ -3907,8 +3947,13 @@ static const struct gprefix three_byte_0f_38_f1 = {
 static const struct opcode opcode_map_0f_38[256] = {
         /* 0x00 - 0x7f */
         X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N),
-        /* 0x80 - 0xff */
-        X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N)
+        /* 0x80 - 0xef */
+        X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N),
+        /* 0xf0 - 0xf1 */
+        GP(EmulateOnUD | ModRM | Prefix, &three_byte_0f_38_f0),
+        GP(EmulateOnUD | ModRM | Prefix, &three_byte_0f_38_f1),
+        /* 0xf2 - 0xff */
+        N, N, X4(N), X8(N)
 };
 
 #undef D