From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1SKq9k-0000iL-Jo for kexec@lists.infradead.org; Thu, 19 Apr 2012 12:08:14 +0000 Message-ID: <4F900020.5010702@redhat.com> Date: Thu, 19 Apr 2012 15:08:00 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [PATCH 0/4] Export offsets of VMCS fields as note information for kdump References: <4F8FEC22.400@redhat.com> <20120419.202707.276752866.d.hatayama@jp.fujitsu.com> <4F8FF7AC.1060309@redhat.com> <20120419.210119.246504497.d.hatayama@jp.fujitsu.com> In-Reply-To: <20120419.210119.246504497.d.hatayama@jp.fujitsu.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: HATAYAMA Daisuke Cc: dzickus@redhat.com, luto@mit.edu, gregkh@suse.de, kvm@vger.kernel.org, joerg.roedel@amd.com, mtosatti@redhat.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, paul.gortmaker@windriver.com, zhangyanfei@cn.fujitsu.com, ebiederm@xmission.com, ludwig.nussel@suse.de On 04/19/2012 03:01 PM, HATAYAMA Daisuke wrote: > >> It would be not helpful for the qemu crash case you are concerned > >> about. We want to use the guest state data to look into guest > >> machine's image in the crasshed qemu. > > > > Why? > > > > It seems natural to check the situation from guest machine's side when > qemu crashs. Suppose a service is running on the guest machine, and > then the qemu crash. Then, we may need to know the details of the > progress of the service if it's important. What has been successfully > done, and what has not yet. How can a service on the guest be related to a qemu crash? And how would guest registers help? You can extract the list of running processes from a qemu crash dump without looking at guest registers. And most vcpus are running asynchronously to qemu, so their register contents is irrelevant (if a vcpu is running synchronously with qemu - it just exited to qemu and is waiting for a response - then you'd see the details in qemu's call stack). -- error compiling committee.c: too many arguments to function _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 0/4] Export offsets of VMCS fields as note information for kdump Date: Thu, 19 Apr 2012 15:08:00 +0300 Message-ID: <4F900020.5010702@redhat.com> References: <4F8FEC22.400@redhat.com> <20120419.202707.276752866.d.hatayama@jp.fujitsu.com> <4F8FF7AC.1060309@redhat.com> <20120419.210119.246504497.d.hatayama@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: dzickus-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, luto-3s7WtUTddSA@public.gmane.org, gregkh-l3A5Bk7waGM@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, joerg.roedel-5C7GfCeVMHo@public.gmane.org, mtosatti-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, paul.gortmaker-CWA4WttNNZF54TAoqtyWWQ@public.gmane.org, zhangyanfei-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, ludwig.nussel-l3A5Bk7waGM@public.gmane.org To: HATAYAMA Daisuke Return-path: In-Reply-To: <20120419.210119.246504497.d.hatayama-+CUm20s59erQFUHtdCDX3A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kexec-bounces-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: kvm.vger.kernel.org On 04/19/2012 03:01 PM, HATAYAMA Daisuke wrote: > >> It would be not helpful for the qemu crash case you are concerned > >> about. We want to use the guest state data to look into guest > >> machine's image in the crasshed qemu. > > > > Why? > > > > It seems natural to check the situation from guest machine's side when > qemu crashs. Suppose a service is running on the guest machine, and > then the qemu crash. Then, we may need to know the details of the > progress of the service if it's important. What has been successfully > done, and what has not yet. How can a service on the guest be related to a qemu crash? And how would guest registers help? You can extract the list of running processes from a qemu crash dump without looking at guest registers. And most vcpus are running asynchronously to qemu, so their register contents is irrelevant (if a vcpu is running synchronously with qemu - it just exited to qemu and is waiting for a response - then you'd see the details in qemu's call stack). -- error compiling committee.c: too many arguments to function From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755307Ab2DSMIU (ORCPT ); Thu, 19 Apr 2012 08:08:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:65274 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755240Ab2DSMIR (ORCPT ); Thu, 19 Apr 2012 08:08:17 -0400 Message-ID: <4F900020.5010702@redhat.com> Date: Thu, 19 Apr 2012 15:08:00 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:11.0) Gecko/20120329 Thunderbird/11.0.1 MIME-Version: 1.0 To: HATAYAMA Daisuke CC: zhangyanfei@cn.fujitsu.com, mtosatti@redhat.com, ebiederm@xmission.com, luto@mit.edu, joerg.roedel@amd.com, dzickus@redhat.com, paul.gortmaker@windriver.com, gregkh@suse.de, ludwig.nussel@suse.de, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH 0/4] Export offsets of VMCS fields as note information for kdump References: <4F8FEC22.400@redhat.com> <20120419.202707.276752866.d.hatayama@jp.fujitsu.com> <4F8FF7AC.1060309@redhat.com> <20120419.210119.246504497.d.hatayama@jp.fujitsu.com> In-Reply-To: <20120419.210119.246504497.d.hatayama@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/19/2012 03:01 PM, HATAYAMA Daisuke wrote: > >> It would be not helpful for the qemu crash case you are concerned > >> about. We want to use the guest state data to look into guest > >> machine's image in the crasshed qemu. > > > > Why? > > > > It seems natural to check the situation from guest machine's side when > qemu crashs. Suppose a service is running on the guest machine, and > then the qemu crash. Then, we may need to know the details of the > progress of the service if it's important. What has been successfully > done, and what has not yet. How can a service on the guest be related to a qemu crash? And how would guest registers help? You can extract the list of running processes from a qemu crash dump without looking at guest registers. And most vcpus are running asynchronously to qemu, so their register contents is irrelevant (if a vcpu is running synchronously with qemu - it just exited to qemu and is waiting for a response - then you'd see the details in qemu's call stack). -- error compiling committee.c: too many arguments to function