Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757282AbaKSVk6 (ORCPT ); Wed, 19 Nov 2014 16:40:58 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:57283 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933211AbaKSVOd (ORCPT ); Wed, 19 Nov 2014 16:14:33 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nadav Amit , Paolo Bonzini Subject: [PATCH 3.14 093/122] KVM: x86: Dont report guest userspace emulation error to userspace Date: Wed, 19 Nov 2014 12:52:23 -0800 Message-Id: <20141119205211.915143085@linuxfoundation.org> X-Mailer: git-send-email 2.1.3 In-Reply-To: <20141119205208.812884198@linuxfoundation.org> References: <20141119205208.812884198@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nadav Amit commit a2b9e6c1a35afcc0973acb72e591c714e78885ff upstream. Commit fc3a9157d314 ("KVM: X86: Don't report L2 emulation failures to user-space") disabled the reporting of L2 (nested guest) emulation failures to userspace due to race-condition between a vmexit and the instruction emulator. The same rational applies also to userspace applications that are permitted by the guest OS to access MMIO area or perform PIO. This patch extends the current behavior - of injecting a #UD instead of reporting it to userspace - also for guest userspace code. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/x86.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4911,7 +4911,7 @@ static int handle_emulation_failure(stru ++vcpu->stat.insn_emulation_fail; trace_kvm_emulate_insn_failed(vcpu); - if (!is_guest_mode(vcpu)) { + if (!is_guest_mode(vcpu) && kvm_x86_ops->get_cpl(vcpu) == 0) { vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; vcpu->run->internal.ndata = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/