From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guryanov Dmitry Subject: Bugs with block devices to domU - let's find solution Date: Tue, 18 Oct 2005 21:06:51 +0400 Message-ID: <43552BAB.8@dgap.mipt.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Hello I have the same bug, that've been disscussed before - domU can't find any block devices and crashes with "Unable to mount root fs". I've spend a week under heavy debugging and find, that this bug take place because dom0 backend driver can't read parameter physical-device from xenstore. For example /local/domain/0/backend/vbd/1/776/physical_device, where 1- domU id, 776=0x308 - major and minor numbers of block device, which will used by domU. This parameter must be written by script /etc/xen/scripts/block, which must start like /etc/xen/scripts/vif-bridge any time as domU starts, but it doesn't. So, there is a question to xen developers: when and how must this script must been started ? P.S. To start domU i comment out block in backend driver, where this parameter must be obtained and give explicitly value for that variable: file - linux-.../drivers/xen/blkback/xenbus.c function - backend_changed replace --------------------- err = xenbus_scanf(NULL, dev->nodename, "physical-device", "%li", &pdev); if (XENBUS_EXIST_ERR(err)) return; --------------------- with, for example: --------------------- pdev=0x307; //hda7 - physical device err=1; --------------------- -- Guryanov Dmitry