KVM: x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

The patch adds in/out instructions to the x86 emulator.

The instruction was encountered while running the BIOS while using
the invalid guest state emulation patch.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 33 insertions, 2 deletions

diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
index 944f1f4d4be4..3ac2f1485223 100644
--- a/arch/x86/kvm/x86_emulate.c
+++ b/arch/x86/kvm/x86_emulate.c
@@ -177,11 +177,14 @@ static u16 opcode_table[256] = {
         /* 0xD8 - 0xDF */
         0, 0, 0, 0, 0, 0, 0, 0,
         /* 0xE0 - 0xE7 */
-        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0,
+        SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
+        SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
         /* 0xE8 - 0xEF */
         ImplicitOps | Stack, SrcImm | ImplicitOps,
         ImplicitOps, SrcImmByte | ImplicitOps,
-        0, 0, 0, 0,
+        SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
+        SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
         /* 0xF0 - 0xF7 */
         0, 0, 0, 0,
         ImplicitOps, ImplicitOps, Group | Group3_Byte, Group | Group3,
@@ -1259,6 +1262,8 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
         u64 msr_data;
         unsigned long saved_eip = 0;
         struct decode_cache *c = &ctxt->decode;
+        unsigned int port;
+        int io_dir_in;
         int rc = 0;
 
         /* Shadow copy of register state. Committed on successful emulation.
@@ -1687,6 +1692,16 @@ special_insn:
                 c->src.val = c->regs[VCPU_REGS_RCX];
                 emulate_grp2(ctxt);
                 break;
+        case 0xe4:      /* inb */
+        case 0xe5:      /* in */
+                port = insn_fetch(u8, 1, c->eip);
+                io_dir_in = 1;
+                goto do_io;
+        case 0xe6: /* outb */
+        case 0xe7: /* out */
+                port = insn_fetch(u8, 1, c->eip);
+                io_dir_in = 0;
+                goto do_io;
         case 0xe8: /* call (near) */ {
                 long int rel;
                 switch (c->op_bytes) {
@@ -1737,6 +1752,22 @@ special_insn:
                 jmp_rel(c, c->src.val);
                 c->dst.type = OP_NONE; /* Disable writeback. */
                 break;
+        case 0xec: /* in al,dx */
+        case 0xed: /* in (e/r)ax,dx */
+                port = c->regs[VCPU_REGS_RDX];
+                io_dir_in = 1;
+                goto do_io;
+        case 0xee: /* out al,dx */
+        case 0xef: /* out (e/r)ax,dx */
+                port = c->regs[VCPU_REGS_RDX];
+                io_dir_in = 0;
+        do_io:  if (kvm_emulate_pio(ctxt->vcpu, NULL, io_dir_in,
+                                   (c->d & ByteOp) ? 1 : c->op_bytes,
+                                   port) != 0) {
+                        c->eip = saved_eip;
+                        goto cannot_emulate;
+                }
+                return 0;
         case 0xf4:              /* hlt */
                 ctxt->vcpu->arch.halt_request = 1;
                 break;