From 91269b8f94eedce1767b2f208d656e5a5683326a Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Sun, 25 Jul 2010 14:51:16 +0300 Subject: [PATCH] KVM: x86 emulator: fix handling for unemulated instructions If an instruction is present in the decode tables but not in the execution switch, it will be emulated as a NOP. An example is IRET (0xcf). Fix by adding default: labels to the execution switches. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 66ca98aafdd6..70e47d3593d8 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3028,6 +3028,8 @@ special_insn: if (c->modrm_reg == 5) goto jump_far; goto grp45; + default: + goto cannot_emulate; } writeback: @@ -3353,6 +3355,8 @@ twobyte_insn: if (rc != X86EMUL_CONTINUE) goto done; break; + default: + goto cannot_emulate; } goto writeback; -- 2.20.1