From patchwork Wed Aug 19 13:02:21 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Avi Kivity X-Patchwork-Id: 42647 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n7JDCrX4022716 for ; Wed, 19 Aug 2009 13:12:58 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752498AbZHSNI7 (ORCPT ); Wed, 19 Aug 2009 09:08:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752569AbZHSNIn (ORCPT ); Wed, 19 Aug 2009 09:08:43 -0400 Received: from mx2.redhat.com ([66.187.237.31]:50572 "EHLO mx2.redhat.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751978AbZHSNCs (ORCPT ); Wed, 19 Aug 2009 09:02:48 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n7JD2o3h005993; Wed, 19 Aug 2009 09:02:50 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n7JD2mjC003275; Wed, 19 Aug 2009 09:02:49 -0400 Received: from cleopatra.tlv.redhat.com (cleopatra.tlv.redhat.com [10.35.255.11]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n7JD2ldT023108; Wed, 19 Aug 2009 09:02:47 -0400 Received: from localhost.localdomain (cleopatra.tlv.redhat.com [10.35.255.11]) by cleopatra.tlv.redhat.com (Postfix) with ESMTP id D5D71250ADD; Wed, 19 Aug 2009 16:02:44 +0300 (IDT) From: Avi Kivity To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH 25/47] KVM: Allow emulation of syscalls instructions on #UD Date: Wed, 19 Aug 2009 16:02:21 +0300 Message-Id: <1250686963-8357-26-git-send-email-avi@redhat.com> In-Reply-To: <1250686963-8357-1-git-send-email-avi@redhat.com> References: <1250686963-8357-1-git-send-email-avi@redhat.com> X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Andre Przywara Add the opcodes for syscall, sysenter and sysexit to the list of instructions handled by the undefined opcode handler. Signed-off-by: Christoph Egger Signed-off-by: Amit Shah Signed-off-by: Andre Przywara Signed-off-by: Avi Kivity --- arch/x86/kvm/x86.c | 33 ++++++++++++++++++++++++++------- 1 files changed, 26 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 892a7a6..57e76b3 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2667,14 +2667,33 @@ int emulate_instruction(struct kvm_vcpu *vcpu, r = x86_decode_insn(&vcpu->arch.emulate_ctxt, &emulate_ops); - /* Reject the instructions other than VMCALL/VMMCALL when - * try to emulate invalid opcode */ + /* Only allow emulation of specific instructions on #UD + * (namely VMMCALL, sysenter, sysexit, syscall)*/ c = &vcpu->arch.emulate_ctxt.decode; - if ((emulation_type & EMULTYPE_TRAP_UD) && - (!(c->twobyte && c->b == 0x01 && - (c->modrm_reg == 0 || c->modrm_reg == 3) && - c->modrm_mod == 3 && c->modrm_rm == 1))) - return EMULATE_FAIL; + if (emulation_type & EMULTYPE_TRAP_UD) { + if (!c->twobyte) + return EMULATE_FAIL; + switch (c->b) { + case 0x01: /* VMMCALL */ + if (c->modrm_mod != 3 || c->modrm_rm != 1) + return EMULATE_FAIL; + break; + case 0x34: /* sysenter */ + case 0x35: /* sysexit */ + if (c->modrm_mod != 0 || c->modrm_rm != 0) + return EMULATE_FAIL; + break; + case 0x05: /* syscall */ + if (c->modrm_mod != 0 || c->modrm_rm != 0) + return EMULATE_FAIL; + break; + default: + return EMULATE_FAIL; + } + + if (!(c->modrm_reg == 0 || c->modrm_reg == 3)) + return EMULATE_FAIL; + } ++vcpu->stat.insn_emulation; if (r) {