From patchwork Fri Oct 12 06:43:43 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yanfei Zhang X-Patchwork-Id: 1585441 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 34E2ADFF71 for ; Fri, 12 Oct 2012 06:44:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755788Ab2JLGow (ORCPT ); Fri, 12 Oct 2012 02:44:52 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:30950 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752864Ab2JLGou (ORCPT ); Fri, 12 Oct 2012 02:44:50 -0400 X-IronPort-AV: E=Sophos;i="4.80,576,1344182400"; d="scan'208";a="5988210" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 12 Oct 2012 14:43:23 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id q9C6imld005764; Fri, 12 Oct 2012 14:44:48 +0800 Received: from localhost.localdomain ([10.167.226.121]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2012101214443669-444312 ; Fri, 12 Oct 2012 14:44:36 +0800 Message-ID: <5077BC1F.7050108@cn.fujitsu.com> Date: Fri, 12 Oct 2012 14:43:43 +0800 From: Zhang Yanfei User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.9) Gecko/20100921 Fedora/3.1.4-1.fc14 Thunderbird/3.1.4 MIME-Version: 1.0 To: x86@kernel.org, kexec@lists.infradead.org, linux-doc@vger.kernel.org, Avi Kivity , mtosatti@redhat.com CC: linux-kernel@vger.kernel.org, "kvm@vger.kernel.org" Subject: [PATCH 1/3] x86/kexec: clear vmcss on all cpus if necessary References: <5077BB7B.4030203@cn.fujitsu.com> In-Reply-To: <5077BB7B.4030203@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/10/12 14:44:36, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/10/12 14:44:37, Serialize complete at 2012/10/12 14:44:37 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch provides an alternative way to clear vmcss related to guests on all cpus when doing kdump. Signed-off-by: zhangyanfei --- arch/x86/include/asm/kexec.h | 3 +++ arch/x86/kernel/crash.c | 23 +++++++++++++++++++++++ 2 files changed, 26 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 317ff17..0692921 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -163,6 +163,9 @@ struct kimage_arch { }; #endif +extern int clear_loaded_vmcs_enabled; +extern void (*crash_clear_loaded_vmcss)(void); + #endif /* __ASSEMBLY__ */ #endif /* _ASM_X86_KEXEC_H */ diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 13ad899..947550e 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -30,6 +31,24 @@ int in_crash_kexec; +/* + * If clear_loaded_vmcs_enabled is set, vmcss + * that are loaded on all cpus will be cleared + * via crash_clear_loaded_vmcss. + */ +int clear_loaded_vmcs_enabled; +void (*crash_clear_loaded_vmcss)(void) = NULL; +EXPORT_SYMBOL_GPL(crash_clear_loaded_vmcss); + +static void cpu_emergency_clear_loaded_vmcss(void) +{ + if (clear_loaded_vmcs_enabled && + crash_clear_loaded_vmcss && + cpu_has_vmx() && cpu_vmx_enabled()) { + crash_clear_loaded_vmcss(); + } +} + #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) static void kdump_nmi_callback(int cpu, struct pt_regs *regs) @@ -46,6 +65,8 @@ static void kdump_nmi_callback(int cpu, struct pt_regs *regs) #endif crash_save_cpu(regs, cpu); + cpu_emergency_clear_loaded_vmcss(); + /* Disable VMX or SVM if needed. * * We need to disable virtualization on all CPUs. @@ -88,6 +109,8 @@ void native_machine_crash_shutdown(struct pt_regs *regs) kdump_nmi_shootdown_cpus(); + cpu_emergency_clear_loaded_vmcss(); + /* Booting kdump kernel with VMX or SVM enabled won't work, * because (among other limitations) we can't disable paging * with the virt flags.