[PATCH v4 16/21] KVM: x86: Reject EVEX-prefixed instructions

[Chang S. Bae]

Explicitly mark EVEX-prefixed opcodes (0x62) as unsupported.

Signed-off-by: Chang S. Bae <chang.seok.bae@xxxxxxxxx>
---
 arch/x86/kvm/emulate.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index efe8adca1317..31118ae3b6a1 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -5052,6 +5052,11 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len, int
 	if (ctxt->d & NoRex2 && ctxt->rex_prefix == REX2_PREFIX)
 		opcode.flags = Undefined;
 
+	/* EVEX-prefixed instructions are not implemented */
+	if (ctxt->opcode_len == 1 && ctxt->b == 0x62 &&
+	    (mode == X86EMUL_MODE_PROT64 || (ctxt->modrm & 0xc0) == 0xc0))
+		opcode.flags = NotImpl;
+
 	if (opcode.flags & ModRM)
 		ctxt->modrm = insn_fetch(u8, ctxt);
 
-- 
2.51.0