Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/tcg/decode-new.h     |  3 +++
 target/i386/tcg/decode-new.c.inc | 21 ++++++++++-----------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/target/i386/tcg/decode-new.h b/target/i386/tcg/decode-new.h
index 92822969003..c974ca9d7c5 100644
--- a/target/i386/tcg/decode-new.h
+++ b/target/i386/tcg/decode-new.h
@@ -181,6 +181,9 @@ typedef enum X86InsnCheck {
     /* Vendor-specific checks for Intel/AMD differences */
     X86_CHECK_i64_amd = 2048,
     X86_CHECK_o64_intel = 4096,
+
+    /* No REX2 prefix allowed */
+    X86_CHECK_no_rex2 = 8192,
 } X86InsnCheck;
 
 typedef enum X86InsnSpecial {
diff --git a/target/i386/tcg/decode-new.c.inc b/target/i386/tcg/decode-new.c.inc
index 6fab597fafc..b968db2b8ad 100644
--- a/target/i386/tcg/decode-new.c.inc
+++ b/target/i386/tcg/decode-new.c.inc
@@ -481,9 +481,9 @@ static void decode_group15(DisasContext *s, CPUX86State *env, X86OpEntry *entry,
         [1] = X86_OP_ENTRYr(FXRSTOR,    M,y, cpuid(FXSR) p_00),
         [2] = X86_OP_ENTRYr(LDMXCSR,    E,d, vex5 chk(VEX128) p_00),
         [3] = X86_OP_ENTRYw(STMXCSR,    E,d, vex5 chk(VEX128) p_00),
-        [4] = X86_OP_ENTRYw(XSAVE,      M,y, cpuid(XSAVE) p_00),
-        [5] = X86_OP_ENTRYr(XRSTOR,     M,y, cpuid(XSAVE) p_00),
-        [6] = X86_OP_ENTRYw(XSAVEOPT,   M,b, cpuid(XSAVEOPT) p_00),
+        [4] = X86_OP_ENTRYw(XSAVE,      M,y, cpuid(XSAVE) p_00 chk(no_rex2)),
+        [5] = X86_OP_ENTRYr(XRSTOR,     M,y, cpuid(XSAVE) p_00 chk(no_rex2)),
+        [6] = X86_OP_ENTRYw(XSAVEOPT,   M,b, cpuid(XSAVEOPT) p_00 chk(no_rex2)),
         [7] = X86_OP_ENTRYw(NOP,        M,b, cpuid(CLFLUSH) p_00),
     };
 
@@ -2963,15 +2963,14 @@ static void disas_insn(DisasContext *s, CPUState *cpu)
                 goto illegal_op;
             }
         }
-        if (decode.e.check & X86_CHECK_prot_or_vm86) {
-            if (!PE(s)) {
-                goto illegal_op;
-            }
+        if ((decode.e.check & X86_CHECK_prot_or_vm86) && !PE(s)) {
+            goto illegal_op;
         }
-        if (decode.e.check & X86_CHECK_no_vm86) {
-            if (VM86(s)) {
-                goto illegal_op;
-            }
+        if ((decode.e.check & X86_CHECK_no_vm86) && VM86(s)) {
+            goto illegal_op;
+        }
+        if ((decode.e.check & X86_CHECK_no_rex2) && (s->prefix & PREFIX_REX2)) {
+            goto illegal_op;
         }
         if ((decode.e.check & X86_CHECK_VEX128) && s->vex_l) {
             goto illegal_op;
-- 
2.52.0