KVM: Implement emulation of "pop reg" instruction (opcode 0x58-0x5f)

For use in real mode.

Signed-off-by: Nitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
index a4a8481..46c3806 100644 (file)
--- a/drivers/kvm/x86_emulate.c
+++ b/drivers/kvm/x86_emulate.c
@@ -98,8 +98,11 @@ static u8 opcode_table[256] = {
        0, 0, 0, 0,
        /* 0x40 - 0x4F */
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-       /* 0x50 - 0x5F */
-       0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+       /* 0x50 - 0x57 */
+       0, 0, 0, 0, 0, 0, 0, 0,
+       /* 0x58 - 0x5F */
+       ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
+       ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
        /* 0x60 - 0x6F */
        0, 0, 0, DstReg | SrcMem32 | ModRM | Mov /* movsxd (x86/64) */ ,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
@@ -1153,6 +1156,16 @@ special_insn:
        case 0xf4:              /* hlt */
                ctxt->vcpu->halt_request = 1;
                goto done;
+       case 0x58 ... 0x5f: /* pop reg */
+               dst.ptr = (unsigned long *)&_regs[b & 0x7];
+
+               if ((rc = ops->read_std(register_address(ctxt->ss_base,
+                       _regs[VCPU_REGS_RSP]), dst.ptr, op_bytes, ctxt)) != 0)
+                       goto done;
+
+               register_address_increment(_regs[VCPU_REGS_RSP], dst.bytes);
+               dst.orig_val = dst.val; /* Disable writeback. */
+               break;
        }
        goto writeback;