From: Wen Congyang Subject: Re: [PATCH v4 2/3] KVM-INTEL: Add new module vmcsinfo-intel to fill VMCSINFO Date: Fri, 06 Jul 2012 16:25:23 +0800 Message-ID: <4FF6A0F3.2010201@cn.fujitsu.com> References: <4FF413D2.4030006@cn.fujitsu.com> <4FF4155F.6070508@cn.fujitsu.com> <20120706.170410.119097767.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, 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, avi-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, ludwig.nussel-l3A5Bk7waGM@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org To: HATAYAMA Daisuke Return-path: In-Reply-To: <20120706.170410.119097767.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 At 07/06/2012 04:04 PM, HATAYAMA Daisuke Wrote: > From: Yanfei Zhang > Subject: [PATCH v4 2/3] KVM-INTEL: Add new module vmcsinfo-intel to fill VMCSINFO > Date: Wed, 4 Jul 2012 18:05:19 +0800 > >> Besides, this patch also exports vmcs revision identifier via >> /sys/devices/system/cpu/vmcs_id and offsets of fields via >> /sys/devices/system/cpu/vmcs/. >> Individual offsets are contained in subfiles named by the filed's >> encoding, e.g.: /sys/devices/cpu/vmcs/0800 > > According to the discussion starting from > > http://lkml.indiana.edu/hypermail/linux/kernel/1105.3/00749.html IIRC, kvm can not work in such environment. The vcpu can run on different cpu. If the cpu's vmcs is different, I don't know what will happen. So do we need to support for such environment now? I think that if kvm can not work in such environment, we should not provide vmcs information for each physical cpu. Thanks Wen Congyang > > system can be composed of CPUs with different steppings or differnet > microcode revisions. Becase of the nature that it's hided in the > specification, I suspect layout of vmcs could change across different > steppings or microcode revisions. Then, the interface needs to be > changed as per-cpu like > > /sys/devices/cpu/cpu0/vmcs/0800 > /sys/devices/cpu/cpu1/vmcs/0800 > ... > /sys/devices/cpu/cpuN/vmcs/0800 > > Also, processing of vmcsinfo initialization needs to be done per cpu, > and can be triggered when cpu is added not when kvm module is loaded. > > Thanks. > HATAYAMA, Daisuke > > > _______________________________________________ > kexec mailing list > kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org > http://lists.infradead.org/mailman/listinfo/kexec >