From patchwork Wed Aug 19 13:02:25 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Avi Kivity X-Patchwork-Id: 42642 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 n7JDCrWx022716 for ; Wed, 19 Aug 2009 13:12:57 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752463AbZHSNHk (ORCPT ); Wed, 19 Aug 2009 09:07:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752267AbZHSNEh (ORCPT ); Wed, 19 Aug 2009 09:04:37 -0400 Received: from mx2.redhat.com ([66.187.237.31]:50585 "EHLO mx2.redhat.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752020AbZHSNCt (ORCPT ); Wed, 19 Aug 2009 09:02:49 -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 n7JD2pFk006045; Wed, 19 Aug 2009 09:02:51 -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 n7JD2nXo003292; 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 n7JD2lcF023110; 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 188DA25004D; Wed, 19 Aug 2009 16:02:45 +0300 (IDT) From: Avi Kivity To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH 29/47] KVM: x86 emulator: Add sysenter emulation Date: Wed, 19 Aug 2009 16:02:25 +0300 Message-Id: <1250686963-8357-30-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 Handle #UD intercept of the sysenter instruction in 32bit compat mode on an AMD host. Setup the segment descriptors for CS and SS and the EIP/ESP registers according to the manual. Signed-off-by: Christoph Egger Signed-off-by: Amit Shah Signed-off-by: Andre Przywara Signed-off-by: Avi Kivity --- arch/x86/kvm/x86_emulate.c | 70 +++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 69 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c index 4d7256d..7a9bddb 100644 --- a/arch/x86/kvm/x86_emulate.c +++ b/arch/x86/kvm/x86_emulate.c @@ -1476,6 +1476,71 @@ emulate_syscall(struct x86_emulate_ctxt *ctxt) return 0; } +static int +emulate_sysenter(struct x86_emulate_ctxt *ctxt) +{ + struct decode_cache *c = &ctxt->decode; + struct kvm_segment cs, ss; + u64 msr_data; + + /* inject #UD if LOCK prefix is used */ + if (c->lock_prefix) + return -1; + + /* inject #GP if in real mode or paging is disabled */ + if (ctxt->mode == X86EMUL_MODE_REAL || + !(ctxt->vcpu->arch.cr0 & X86_CR0_PE)) { + kvm_inject_gp(ctxt->vcpu, 0); + return -1; + } + + /* XXX sysenter/sysexit have not been tested in 64bit mode. + * Therefore, we inject an #UD. + */ + if (ctxt->mode == X86EMUL_MODE_PROT64) + return -1; + + setup_syscalls_segments(ctxt, &cs, &ss); + + kvm_x86_ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_CS, &msr_data); + switch (ctxt->mode) { + case X86EMUL_MODE_PROT32: + if ((msr_data & 0xfffc) == 0x0) { + kvm_inject_gp(ctxt->vcpu, 0); + return -1; + } + break; + case X86EMUL_MODE_PROT64: + if (msr_data == 0x0) { + kvm_inject_gp(ctxt->vcpu, 0); + return -1; + } + break; + } + + ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF); + cs.selector = (u16)msr_data; + cs.selector &= ~SELECTOR_RPL_MASK; + ss.selector = cs.selector + 8; + ss.selector &= ~SELECTOR_RPL_MASK; + if (ctxt->mode == X86EMUL_MODE_PROT64 + || is_long_mode(ctxt->vcpu)) { + cs.db = 0; + cs.l = 1; + } + + kvm_x86_ops->set_segment(ctxt->vcpu, &cs, VCPU_SREG_CS); + kvm_x86_ops->set_segment(ctxt->vcpu, &ss, VCPU_SREG_SS); + + kvm_x86_ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_EIP, &msr_data); + c->eip = msr_data; + + kvm_x86_ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_ESP, &msr_data); + c->regs[VCPU_REGS_RSP] = msr_data; + + return 0; +} + int x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { @@ -2144,7 +2209,10 @@ twobyte_insn: c->dst.type = OP_NONE; break; case 0x34: /* sysenter */ - goto cannot_emulate; + if (emulate_sysenter(ctxt) == -1) + goto cannot_emulate; + else + goto writeback; break; case 0x35: /* sysexit */ goto cannot_emulate;