Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751662Ab2KPKOp (ORCPT ); Fri, 16 Nov 2012 05:14:45 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:31597 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751469Ab2KPKOo convert rfc822-to-8bit (ORCPT ); Fri, 16 Nov 2012 05:14:44 -0500 X-IronPort-AV: E=Sophos;i="4.83,263,1352044800"; d="scan'208";a="6214410" Message-ID: <50A611AA.6030903@cn.fujitsu.com> Date: Fri, 16 Nov 2012 18:12:58 +0800 From: zhangyanfei User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.8) Gecko/20121012 Thunderbird/10.0.8 MIME-Version: 1.0 To: "x86@kernel.org" , "kexec@lists.infradead.org" , Avi Kivity , Marcelo Tosatti CC: "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" Subject: Re: [PATCH v4 0/2] x86: clear vmcss on all cpus when doing kdump if necessary References: <50A3645F.60302@cn.fujitsu.com> In-Reply-To: <50A3645F.60302@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/11/16 18:14:33, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/11/16 18:14:34 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1921 Lines: 50 Hello Marcelo, Any thoughts? 于 2012年11月14日 17:29, zhangyanfei 写道: > Currently, kdump just makes all the logical processors leave VMX operation by > executing VMXOFF instruction, so any VMCSs active on the logical processors may > be corrupted. But, sometimes, we need the VMCSs to debug guest images contained > in the host vmcore. To prevent the corruption, we should VMCLEAR the VMCSs before > executing the VMXOFF instruction. > > The patch set provides a way to VMCLEAR vmcss related to guests on all cpus before > executing the VMXOFF when doing kdump. This is used to ensure the VMCSs in the > vmcore updated and non-corrupted. > > Changelog from v3 to v4: > 1. add a new percpu variable vmclear_skipped to skip > vmclear in kdump in some conditions. > > Changelog from v2 to v3: > 1. remove unnecessary conditions in function > cpu_emergency_clear_loaded_vmcss as Marcelo suggested. > > Changelog from v1 to v2: > 1. remove the sysctl and clear VMCSs unconditionally. > > Zhang Yanfei (2): > x86/kexec: VMCLEAR vmcss on all cpus if necessary > KVM: set/unset crash_clear_loaded_vmcss and vmclear_skipped in > kvm_intel module > > arch/x86/include/asm/kexec.h | 3 +++ > arch/x86/kernel/crash.c | 32 ++++++++++++++++++++++++++++++++ > arch/x86/kvm/vmx.c | 32 ++++++++++++++++++++++++++++++++ > 3 files changed, 67 insertions(+), 0 deletions(-) > > > -- > 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/ > -- 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/