From: Avi Kivity <avi@redhat.com>
Date: Wed, 13 Jun 2012 13:33:29 +0000 (+0300)
Subject: KVM: x86 emulator: implement LTR
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=80890006167ec3e570bfd7cee7a05db17d339726;p=linux-beck.git

KVM: x86 emulator: implement LTR

Opcode 0F 00 /3.  Encountered during Windows XP secondary processor bringup.

Signed-off-by: Avi Kivity <avi@redhat.com>
---

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 92a1adde0b44..97d9a9914ba8 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3033,6 +3033,15 @@ static int em_lldt(struct x86_emulate_ctxt *ctxt)
 	return load_segment_descriptor(ctxt, sel, VCPU_SREG_LDTR);
 }
 
+static int em_ltr(struct x86_emulate_ctxt *ctxt)
+{
+	u16 sel = ctxt->src.val;
+
+	/* Disable writeback. */
+	ctxt->dst.type = OP_NONE;
+	return load_segment_descriptor(ctxt, sel, VCPU_SREG_TR);
+}
+
 static int em_invlpg(struct x86_emulate_ctxt *ctxt)
 {
 	int rc;
@@ -3579,7 +3588,7 @@ static struct opcode group6[] = {
 	DI(Prot,	sldt),
 	DI(Prot,	str),
 	II(Prot | Priv | SrcMem16, em_lldt, lldt),
-	DI(Prot | Priv,	ltr),
+	II(Prot | Priv | SrcMem16, em_ltr, ltr),
 	N, N, N, N,
 };