From a77ab5ead5c1fef2c6c5a9b3cf3765e52643a2aa Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 5 Jan 2009 13:27:34 +0200 Subject: KVM: x86 emulator: implement 'ret far' instruction (opcode 0xcb) Signed-off-by: Avi Kivity --- arch/x86/kvm/x86_emulate.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c index 94459f313f1..ca91749d208 100644 --- a/arch/x86/kvm/x86_emulate.c +++ b/arch/x86/kvm/x86_emulate.c @@ -178,7 +178,7 @@ static u32 opcode_table[256] = { 0, ImplicitOps | Stack, 0, 0, ByteOp | DstMem | SrcImm | ModRM | Mov, DstMem | SrcImm | ModRM | Mov, /* 0xC8 - 0xCF */ - 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, ImplicitOps | Stack, 0, 0, 0, 0, /* 0xD0 - 0xD7 */ ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM, ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM, @@ -1278,6 +1278,25 @@ static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt, return 0; } +static int emulate_ret_far(struct x86_emulate_ctxt *ctxt, + struct x86_emulate_ops *ops) +{ + struct decode_cache *c = &ctxt->decode; + int rc; + unsigned long cs; + + rc = emulate_pop(ctxt, ops, &c->eip, c->op_bytes); + if (rc) + return rc; + if (c->op_bytes == 4) + c->eip = (u32)c->eip; + rc = emulate_pop(ctxt, ops, &cs, c->op_bytes); + if (rc) + return rc; + rc = kvm_load_segment_descriptor(ctxt->vcpu, (u16)cs, 1, VCPU_SREG_CS); + return rc; +} + static inline int writeback(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { @@ -1735,6 +1754,11 @@ special_insn: mov: c->dst.val = c->src.val; break; + case 0xcb: /* ret far */ + rc = emulate_ret_far(ctxt, ops); + if (rc) + goto done; + break; case 0xd0 ... 0xd1: /* Grp2 */ c->src.val = 1; emulate_grp2(ctxt); -- cgit v1.2.3