Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754837AbbBONCP (ORCPT ); Sun, 15 Feb 2015 08:02:15 -0500 Received: from mail-lb0-f177.google.com ([209.85.217.177]:38591 "EHLO mail-lb0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754656AbbBONCN (ORCPT ); Sun, 15 Feb 2015 08:02:13 -0500 MIME-Version: 1.0 In-Reply-To: <20150215062755.GA2603@ywang-linux> References: <1422979097-2203-1-git-send-email-fanwenyi0529@gmail.com> <20150215062755.GA2603@ywang-linux> From: Wincy Van Date: Sun, 15 Feb 2015 21:01:51 +0800 Message-ID: Subject: Re: [PATCH resend v5 6/6] KVM: nVMX: Enable nested posted interrupt processing To: Yong Wang Cc: Paolo Bonzini , "gleb@kernel.org" , "Zhang, Yang Z" , Wanpeng Li , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Jan Kiszka Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2678 Lines: 78 On Sun, Feb 15, 2015 at 2:27 PM, Yong Wang wrote: > On Tue, Feb 03, 2015 at 11:58:17PM +0800, Wincy Van wrote: >> If vcpu has a interrupt in vmx non-root mode, we will >> kick that vcpu to inject interrupt timely. With posted >> interrupt processing, the kick intr is not needed, and >> interrupts are fully taken care of by hardware. >> >> In nested vmx, this feature avoids much more vmexits >> than non-nested vmx. >> >> This patch use L0's POSTED_INTR_NV to avoid unexpected >> interrupt if L1's vector is different with L0's. If vcpu >> is in hardware's non-root mode, we use a physical ipi to >> deliver posted interrupts, otherwise we will accomplish >> that posted interrupt in nested vm-entry manually. >> >> Signed-off-by: Wincy Van >> --- >> arch/x86/kvm/lapic.c | 13 +++- >> arch/x86/kvm/lapic.h | 1 + >> arch/x86/kvm/vmx.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++++- >> 3 files changed, 158 insertions(+), 7 deletions(-) >> > > Wincy, our QA found regressions with this patch that 64bit L2 linux guest > fails to boot up when running nested kvm on kvm. > > Environment: > ------------ > Host OS (ia32/ia32e/IA64):ia32e > Guest OS (ia32/ia32e/IA64):ia32e > Guest OS Type (Linux/Windows):Linux > kvm.git Commit:6557bada461afeaa920a189fae2cff7c8fdce39f > qemu.kvm Commit:5c697ae74170d43928cb185f5ac1a9058adcae0b > Host Kernel Version:3.19.0-rc3 > Hardware:Ivytown_EP, Haswell_EP > > > Bug detailed description: > -------------------------- > create 64bit linux guest as L2 guest, the guest boot up fail > > note: > 1. create a 32bit linux guest as L2 guest, the guest boots up fine. > 2. create a 64bit windows guest as L2 guest, the guest boots up fine. > 3. this should be a kernel bug: > kvm + qemu = result > 6557bada + 5c697ae7 = bad > 8fff5e37 + 5c697ae7 = good > > Reproduce steps: > ---------------- > 1 create L1 guest: > qemu-system-x86_64 -enable-kvm -m 8G -smp 4 -net nic,macaddr=00:12:31:34:51:31 -net tap,script=/etc/kvm/qemu-ifup nested-kvm.qcow -cpu host > > 2. create L2 guest > qemu-system-x86_64 -enable-kvm -m 2G -smp 2 -net none rhel6u5.qcow > > Current result: > ---------------- > create 64bit linux guest as L2 guest, the guest boots up fail > > Expected result: > ---------------- > create 64bit linux guest as L2 guest, the guest boots up fine > > Please take a look. > Certainly, will do. Thanks, Wincy -- 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/