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: Tue, 17 Apr 2012 10:44:06 +0300 Message-ID: <4F8D1F46.3090901@redhat.com> References: <4F84E0DF.8040206@cn.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, ludwig.nussel-l3A5Bk7waGM@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org To: zhangyanfei Return-path: In-Reply-To: <4F84E0DF.8040206-BthXqXjhjHXQFUHtdCDX3A@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 04/11/2012 04:39 AM, zhangyanfei wrote: > This patch set exports offsets of VMCS fields as note information for > kdump. We call it VMCSINFO. The purpose of VMCSINFO is to retrieve > runtime state of guest machine image, such as registers, in host > machine's crash dump as VMCS format. The problem is that VMCS > internal is hidden by Intel in its specification. So, we reverse > engineering it in the way implemented in this patch set. Please note > that this processing never affects any existing kvm logic. The > VMCSINFO is exported via sysfs to kexec-tools just like VMCOREINFO. > > Here is an example: > Processor: Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz > > $cat /sys/kernel/vmcsinfo > 1cba8c0 2000 > > crash> rd -p 1cba8c0 1000 > 1cba8c0: 0000127b00000009 53434d5600000000 ....{.......VMCS > 1cba8d0: 000000004f464e49 4e4f495349564552 INFO....REVISION > 1cba8e0: 49460a643d44495f 5f4e495028444c45 _ID=d.FIELD(PIN_ > 1cba8f0: 4d565f4445534142 4f435f434558455f BASED_VM_EXEC_CO > 1cba900: 303d294c4f52544e 0a30383130343831 NTROL)=01840180. > 1cba910: 504328444c454946 5f44455341425f55 FIELD(CPU_BASED_ > 1cba920: 5f434558455f4d56 294c4f52544e4f43 VM_EXEC_CONTROL) > 1cba930: 393130343931303d 28444c4549460a30 =01940190.FIELD( > 1cba940: 5241444e4f434553 4558455f4d565f59 SECONDARY_VM_EXE > 1cba950: 4f52544e4f435f43 30346566303d294c C_CONTROL)=0fe40 > 1cba960: 4c4549460a306566 4958455f4d562844 fe0.FIELD(VM_EXI > 1cba970: 4f52544e4f435f54 346531303d29534c T_CONTROLS)=01e4 > 1cba980: 4549460a30653130 4e455f4d5628444c 01e0.FIELD(VM_EN > 1cba990: 544e4f435f595254 33303d29534c4f52 TRY_CONTROLS)=03 > 1cba9a0: 460a303133303431 45554728444c4549 140310.FIELD(GUE > 1cba9b0: 45535f53455f5453 3d29524f5443454c ST_ES_SELECTOR)= > 1cba9c0: 4549460a30303530 545345554728444c 0500.FIELD(GUEST > 1cba9d0: 454c45535f53435f 35303d29524f5443 _CS_SELECTOR)=05 > ...... > > TODO: > 1. In kexec-tools, get VMCSINFO via sysfs and dump it as note information > into vmcore. > 2. Dump VMCS region of each guest vcpu and VMCSINFO into qemu-process > core file. To do this, we will modify kernel core dumper, gdb gcore > and crash gcore. > 3. Dump guest image from the qemu-process core file into a vmcore. > Taking a step back, can you describe the problem scenario you're fixing here? -- error compiling committee.c: too many arguments to function