From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: KVM call agenda for Mar 16 Date: Tue, 16 Mar 2010 10:05:40 -0500 Message-ID: <4B9F9E44.9050807@codemonkey.ws> References: <20100316070155.GK3732@x200.localdomain> <20100316092944.GB23617@redhat.com> <4B9F52D4.2030208@redhat.com> <20100316103146.GF23617@redhat.com> <4B9F5F8A.4080105@redhat.com> <20100316104537.GH23617@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Juan Quintela , Chris Wright , kvm@vger.kernel.org, qemu-devel@nongnu.org To: "Daniel P. Berrange" Return-path: Received: from mail-pw0-f46.google.com ([209.85.160.46]:62719 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966326Ab0CPPHQ (ORCPT ); Tue, 16 Mar 2010 11:07:16 -0400 Received: by pwi1 with SMTP id 1so35975pwi.19 for ; Tue, 16 Mar 2010 08:07:15 -0700 (PDT) In-Reply-To: <20100316104537.GH23617@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 03/16/2010 05:45 AM, Daniel P. Berrange wrote: > On Tue, Mar 16, 2010 at 12:38:02PM +0200, Avi Kivity wrote: > >> On 03/16/2010 12:31 PM, Daniel P. Berrange wrote: >> >>>> Polling loops are an indication that something is wrong. >>>> >>>> >>> Except when people suggest they are the right answer, qcow high >>> watermark ;-P >>> >>> >> I liked Anthony's suggestion of an lvm2 block format driver. No polling. >> > Doesn't that require giving QEMU privileges to perform LVM operations which > implies QEMU having CAP_SYS_ADMIN ? > If QEMU is able to resize an LVM partition, it needs to carry privileges. I'm not sure how this can be done safely in a lesser privileged environment. Presumably, you're over committing storage and there's not much you can do if the guests exhaust their storage all at once. Regards, Anthony Liguori > Daniel > From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NrYMZ-0008Ba-8B for qemu-devel@nongnu.org; Tue, 16 Mar 2010 11:07:19 -0400 Received: from [199.232.76.173] (port=34428 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NrYMY-0008AO-8k for qemu-devel@nongnu.org; Tue, 16 Mar 2010 11:07:18 -0400 Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1NrYMX-0004kC-0z for qemu-devel@nongnu.org; Tue, 16 Mar 2010 11:07:18 -0400 Received: from mail-pz0-f194.google.com ([209.85.222.194]:52435) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NrYMW-0004k6-Jr for qemu-devel@nongnu.org; Tue, 16 Mar 2010 11:07:16 -0400 Received: by pzk32 with SMTP id 32so478064pzk.4 for ; Tue, 16 Mar 2010 08:07:15 -0700 (PDT) Message-ID: <4B9F9E44.9050807@codemonkey.ws> Date: Tue, 16 Mar 2010 10:05:40 -0500 From: Anthony Liguori MIME-Version: 1.0 References: <20100316070155.GK3732@x200.localdomain> <20100316092944.GB23617@redhat.com> <4B9F52D4.2030208@redhat.com> <20100316103146.GF23617@redhat.com> <4B9F5F8A.4080105@redhat.com> <20100316104537.GH23617@redhat.com> In-Reply-To: <20100316104537.GH23617@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: KVM call agenda for Mar 16 List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Chris Wright , qemu-devel@nongnu.org, Avi Kivity , kvm@vger.kernel.org, Juan Quintela On 03/16/2010 05:45 AM, Daniel P. Berrange wrote: > On Tue, Mar 16, 2010 at 12:38:02PM +0200, Avi Kivity wrote: > >> On 03/16/2010 12:31 PM, Daniel P. Berrange wrote: >> >>>> Polling loops are an indication that something is wrong. >>>> >>>> >>> Except when people suggest they are the right answer, qcow high >>> watermark ;-P >>> >>> >> I liked Anthony's suggestion of an lvm2 block format driver. No polling. >> > Doesn't that require giving QEMU privileges to perform LVM operations which > implies QEMU having CAP_SYS_ADMIN ? > If QEMU is able to resize an LVM partition, it needs to carry privileges. I'm not sure how this can be done safely in a lesser privileged environment. Presumably, you're over committing storage and there's not much you can do if the guests exhaust their storage all at once. Regards, Anthony Liguori > Daniel >