KVM: x86 emulator: Use opcode::execute for MOV to cr/dr

MOV: 0F 22 (move to control registers)
MOV: 0F 23 (move to debug registers)

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 30 insertions, 22 deletions

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 6b7a03b18f89..7fe5ed126f6f 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2638,6 +2638,34 @@ static int em_mov(struct x86_emulate_ctxt *ctxt)
         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))
+                return emulate_gp(ctxt, 0);
+
+        /* Disable writeback. */
+        ctxt->dst.type = OP_NONE;
+        return X86EMUL_CONTINUE;
+}
+
+static int em_dr_write(struct x86_emulate_ctxt *ctxt)
+{
+        unsigned long val;
+
+        if (ctxt->mode == X86EMUL_MODE_PROT64)
+                val = ctxt->src.val & ~0ULL;
+        else
+                val = ctxt->src.val & ~0U;
+
+        /* #UD condition is already handled. */
+        if (ctxt->ops->set_dr(ctxt, ctxt->modrm_reg, val) < 0)
+                return emulate_gp(ctxt, 0);
+
+        /* Disable writeback. */
+        ctxt->dst.type = OP_NONE;
+        return X86EMUL_CONTINUE;
+}
+
 static int em_mov_rm_sreg(struct x86_emulate_ctxt *ctxt)
 {
         if (ctxt->modrm_reg > VCPU_SREG_GS)
@@ -3304,8 +3332,8 @@ static struct opcode twobyte_table[256] = {
         /* 0x20 - 0x2F */
         DIP(ModRM | DstMem | Priv | Op3264, cr_read, check_cr_read),
         DIP(ModRM | DstMem | Priv | Op3264, dr_read, check_dr_read),
-        DIP(ModRM | SrcMem | Priv | Op3264, cr_write, check_cr_write),
-        DIP(ModRM | SrcMem | Priv | Op3264, dr_write, check_dr_write),
+        IIP(ModRM | SrcMem | Priv | Op3264, em_cr_write, cr_write, check_cr_write),
+        IIP(ModRM | SrcMem | Priv | Op3264, em_dr_write, dr_write, check_dr_write),
         N, N, N, N,
         N, N, N, N, N, N, N, N,
         /* 0x30 - 0x3F */
@@ -4080,26 +4108,6 @@ twobyte_insn:
         case 0x21: /* mov from dr to reg */
                 ops->get_dr(ctxt, ctxt->modrm_reg, &ctxt->dst.val);
                 break;
-        case 0x22: /* mov reg, cr */
-                if (ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val)) {
-                        emulate_gp(ctxt, 0);
-                        rc = X86EMUL_PROPAGATE_FAULT;
-                        goto done;
-                }
-                ctxt->dst.type = OP_NONE;
-                break;
-        case 0x23: /* mov from reg to dr */
-                if (ops->set_dr(ctxt, ctxt->modrm_reg, ctxt->src.val &
-                                ((ctxt->mode == X86EMUL_MODE_PROT64) ?
-                                 ~0ULL : ~0U)) < 0) {
-                        /* #UD condition is already handled by the code above */
-                        emulate_gp(ctxt, 0);
-                        rc = X86EMUL_PROPAGATE_FAULT;
-                        goto done;
-                }
-
-                ctxt->dst.type = OP_NONE;       /* no writeback */
-                break;
         case 0x30:
                 /* wrmsr */
                 msr_data = (u32)ctxt->regs[VCPU_REGS_RAX]