From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753954Ab2KZBwE (ORCPT ); Sun, 25 Nov 2012 20:52:04 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:6969 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753501Ab2KZBwC convert rfc822-to-8bit (ORCPT ); Sun, 25 Nov 2012 20:52:02 -0500 X-IronPort-AV: E=Sophos;i="4.83,317,1352044800"; d="scan'208";a="6272129" Message-ID: <50B2CACD.2000103@cn.fujitsu.com> Date: Mon, 26 Nov 2012 09:50:05 +0800 From: Zhang Yanfei User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.8) Gecko/20121012 Thunderbird/10.0.8 MIME-Version: 1.0 To: Gleb Natapov CC: "x86@kernel.org" , "kexec@lists.infradead.org" , Marcelo Tosatti , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" Subject: Re: [PATCH v8 0/2] x86: vmclear vmcss on all cpus when doing kdump if necessary References: <50ADE0C2.1000106@cn.fujitsu.com> <20121125142642.GC25516@redhat.com> In-Reply-To: <20121125142642.GC25516@redhat.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/11/26 09:51:35, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/11/26 09:51:37 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 于 2012年11月25日 22:26, Gleb Natapov 写道: > On Thu, Nov 22, 2012 at 04:22:26PM +0800, Zhang Yanfei wrote: >> 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. >> > Looks fine to me, but kexec part should get acks from exec maintainers. Thanks. I will ask the exec maintainer. > >> Changelog from v7 to v8: >> 1. KEXEC: regression for using name crash_notifier_list >> and remove comments related to KVM >> and just call function atomic_notifier_call_chain directly. >> >> Changelog from v6 to v7: >> 1. KVM-INTEL: in hardware_disable, we needn't disable the >> vmclear, so remove it. >> >> Changelog from v5 to v6: >> 1. KEXEC: the atomic notifier list renamed: >> crash_notifier_list --> vmclear_notifier_list >> 2. KVM-INTEL: provide empty functions if CONFIG_KEXEC is >> not defined and remove unnecessary #ifdef's. >> >> Changelog from v4 to v5: >> 1. use an atomic notifier instead of function call, so >> have all the vmclear codes in vmx.c. >> >> 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: add a new atomic notifier list for kdump >> KVM-INTEL: add a notifier and a bitmap to support VMCLEAR in kdump >> >> arch/x86/include/asm/kexec.h | 2 + >> arch/x86/kernel/crash.c | 9 +++++ >> arch/x86/kvm/vmx.c | 70 ++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 81 insertions(+), 0 deletions(-) > > -- > Gleb. >