From 10db61fb596b1382e8f5fdd8178530979fc6d135 Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Mon, 9 Apr 2012 18:39:59 +0300
Subject: [PATCH] --- yaml --- r: 307861 b: refs/heads/master c:
 1c11b37669a5209bd11fb857a103634afef971e8 h: refs/heads/master i:   307859:
 f39f21a3ac27d399fa2e883aa913b06eebb70f75 v: v3

---
 [refs]                       |  2 +-
 trunk/arch/x86/kvm/emulate.c | 30 +++++++++++++++++++++++++++++-
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index e0c7838760c3..3823f151afe8 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ae75954457eee0a608072368c5b477e40f378d7b
+refs/heads/master: 1c11b37669a5209bd11fb857a103634afef971e8
diff --git a/trunk/arch/x86/kvm/emulate.c b/trunk/arch/x86/kvm/emulate.c
index 83756223f8aa..6302e5c74341 100644
--- a/trunk/arch/x86/kvm/emulate.c
+++ b/trunk/arch/x86/kvm/emulate.c
@@ -142,6 +142,9 @@
 #define Src2FS      (OpFS << Src2Shift)
 #define Src2GS      (OpGS << Src2Shift)
 #define Src2Mask    (OpMask << Src2Shift)
+#define Aligned     ((u64)1 << 41)  /* Explicitly aligned (e.g. MOVDQA) */
+#define Unaligned   ((u64)1 << 42)  /* Explicitly unaligned (e.g. MOVDQU) */
+#define Avx         ((u64)1 << 43)  /* Advanced Vector Extensions */
 
 #define X2(x...) x, x
 #define X3(x...) X2(x), x
@@ -557,6 +560,29 @@ static void set_segment_selector(struct x86_emulate_ctxt *ctxt, u16 selector,
 	ctxt->ops->set_segment(ctxt, selector, &desc, base3, seg);
 }
 
+/*
+ * x86 defines three classes of vector instructions: explicitly
+ * aligned, explicitly unaligned, and the rest, which change behaviour
+ * depending on whether they're AVX encoded or not.
+ *
+ * Also included is CMPXCHG16B which is not a vector instruction, yet it is
+ * subject to the same check.
+ */
+static bool insn_aligned(struct x86_emulate_ctxt *ctxt, unsigned size)
+{
+	if (likely(size < 16))
+		return false;
+
+	if (ctxt->d & Aligned)
+		return true;
+	else if (ctxt->d & Unaligned)
+		return false;
+	else if (ctxt->d & Avx)
+		return false;
+	else
+		return true;
+}
+
 static int __linearize(struct x86_emulate_ctxt *ctxt,
 		     struct segmented_address addr,
 		     unsigned size, bool write, bool fetch,
@@ -621,6 +647,8 @@ static int __linearize(struct x86_emulate_ctxt *ctxt,
 	}
 	if (fetch ? ctxt->mode != X86EMUL_MODE_PROT64 : ctxt->ad_bytes != 8)
 		la &= (u32)-1;
+	if (insn_aligned(ctxt, size) && ((la & (size - 1)) != 0))
+		return emulate_gp(ctxt, 0);
 	*linear = la;
 	return X86EMUL_CONTINUE;
 bad:
@@ -3415,7 +3443,7 @@ static struct opcode group11[] = {
 };
 
 static struct gprefix pfx_0f_6f_0f_7f = {
-	N, N, N, I(Sse, em_movdqu),
+	N, N, N, I(Sse | Unaligned, em_movdqu),
 };
 
 static struct opcode opcode_table[256] = {