From: Nadav Amit <namit@cs.technion.ac.il>
Date: Sun, 2 Nov 2014 09:54:55 +0000 (+0200)
Subject: KVM: x86: Combine the lgdt and lidt emulation logic
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=5b7f6a1e6f6cb6537694a9bbd43bb4ee5a6d8bc2;p=linux-beck.git

KVM: x86: Combine the lgdt and lidt emulation logic

LGDT and LIDT emulation logic is almost identical. Merge the logic into a
single point to avoid redundancy. This will be used by the next patch that
will ensure the bases of the loaded GDTR and IDTR are canonical.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 9f960b428bb2..c86b3781fca2 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3327,7 +3327,7 @@ static int em_sidt(struct x86_emulate_ctxt *ctxt)
 	return emulate_store_desc_ptr(ctxt, ctxt->ops->get_idt);
 }
 
-static int em_lgdt(struct x86_emulate_ctxt *ctxt)
+static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt)
 {
 	struct desc_ptr desc_ptr;
 	int rc;
@@ -3339,12 +3339,20 @@ static int em_lgdt(struct x86_emulate_ctxt *ctxt)
 			     ctxt->op_bytes);
 	if (rc != X86EMUL_CONTINUE)
 		return rc;
-	ctxt->ops->set_gdt(ctxt, &desc_ptr);
+	if (lgdt)
+		ctxt->ops->set_gdt(ctxt, &desc_ptr);
+	else
+		ctxt->ops->set_idt(ctxt, &desc_ptr);
 	/* Disable writeback. */
 	ctxt->dst.type = OP_NONE;
 	return X86EMUL_CONTINUE;
 }
 
+static int em_lgdt(struct x86_emulate_ctxt *ctxt)
+{
+	return em_lgdt_lidt(ctxt, true);
+}
+
 static int em_vmmcall(struct x86_emulate_ctxt *ctxt)
 {
 	int rc;
@@ -3358,20 +3366,7 @@ static int em_vmmcall(struct x86_emulate_ctxt *ctxt)
 
 static int em_lidt(struct x86_emulate_ctxt *ctxt)
 {
-	struct desc_ptr desc_ptr;
-	int rc;
-
-	if (ctxt->mode == X86EMUL_MODE_PROT64)
-		ctxt->op_bytes = 8;
-	rc = read_descriptor(ctxt, ctxt->src.addr.mem,
-			     &desc_ptr.size, &desc_ptr.address,
-			     ctxt->op_bytes);
-	if (rc != X86EMUL_CONTINUE)
-		return rc;
-	ctxt->ops->set_idt(ctxt, &desc_ptr);
-	/* Disable writeback. */
-	ctxt->dst.type = OP_NONE;
-	return X86EMUL_CONTINUE;
+	return em_lgdt_lidt(ctxt, false);
 }
 
 static int em_smsw(struct x86_emulate_ctxt *ctxt)