From mboxrd@z Thu Jan 1 00:00:00 1970 From: listmail Subject: Re: Xen Dom U kernel Date: Mon, 19 Apr 2010 17:29:36 -0400 Message-ID: <4BCCCB40.9080803@triad.rr.com> References: <4BC60244.5070300@goop.org> <20100417122221.GI1878@reaktio.net> <20100419192755.GT1878@reaktio.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20100419192755.GT1878@reaktio.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: =?ISO-8859-1?Q?Pasi_K=E4rkk=E4inen?= Cc: xen-devel@lists.xensource.com, xen-users@lists.xensource.com, kishore kumar List-Id: xen-devel@lists.xenproject.org I don't have any issues using my dom0 kernel & initrd to boot pv domU, =20 config has CONFIG_XEN_BLKDEV_FRONTEND=3Dm as well. However, thats when passing through file based images & LVM from the=20 dom0 to the domU. Is this more of an issue when LVM is implemented on=20 the domU itself??? That's what I am seeing here. Should he be adding a=20 break=3Dpremount option to initrd and checking visibility of the LVM root= =20 from busybox? Pasi K=E4rkk=E4inen wrote: > On Mon, Apr 19, 2010 at 12:08:35PM -0700, kishore kumar wrote: > =20 >> I included >> kernel =3D "/boot/vmlinuz-2.6.32.10" >> ramdisk =3D "/boot/initrd-2.6.32.10.img" (This is the same as my Do= m 0. As >> I am trying to boot the same Dom 0 as my Dom U without any changes) >> >> =20 > > You cannot use the dom0 initrd/ramdisk for domU! > > dom0 initrd contains drivers for the physical hardware, while in the do= mU initrd > you need to have drivers for the _virtual_ hardware! > > In the log below root was not found because the drivers for the xen blo= ck devices > are not loaded. > > -- Pasi > > > =20 >> disk =3D ['phy:sda2,sda2,w'] >> root=3D "/dev/VolGroup01/LogVol00 ro" >> >> I see my .config and I have >> CONFIG_XEN_BLKDEV_FRONTEND=3Dm >> CONFIG_XEN_BLKDEV_BACKEND=3Dy >> CONFIG_XEN_BACKEND=3Dy >> >> Below is the output pasted. Any help please on what is going wrong= here? >> >> XENBUS: Device with no driver: device/vbd/2050 >> >> XENBUS: Device with no driver: device/vif/0 >> >> XENBUS: Device with no driver: device/console/0 >> >> Magic number: 1:252:3141 >> >> drivers/rtc/hctosys.c: unable to open rtc device (rtc0) >> >> Initalizing network drop monitor service >> >> Freeing unused kernel memory: 3392k freed >> >> Write protecting the kernel read-only data: 6912k >> >> Red Hat nash version 5.1.19.6 starting >> >> Mounting proc filesystem >> >> Mounting sysfs filesystem >> >> Creating /dev >> >> Creating initial device nodes >> >> Setting up hotplug. >> >> Creating block device nodes. >> >> Loading ehci-hcd.ko module >> >> ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver >> >> insmod used greatest stack depth: 5712 bytes left >> >> Loading ssb.ko module >> >> Loading ohci-hcd.ko module >> >> ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver >> >> Loading uhci-hcd.ko module >> >> uhci_hcd: USB Universal Host Controller Interface driver >> >> Scanning and configuring dmraid supported devices >> >> Scanning logical volumes >> >> Reading all physical volumes. This may take a while... >> >> lvm used greatest stack depth: 5328 bytes left >> >> Activating logical volumes >> >> Volume group "VolGroup01" not found >> >> Trying to resume from /dev/VolGroup01/LogVol01 >> >> Unable to access resume device (/dev/VolGroup01/LogVol01) >> >> Creating root device. >> >> Mounting root filesystem. >> >> mount: could not find filesystem '/dev/root' >> >> Setting up other filesystems. >> >> Setting up new root fs >> >> setuproot: moving /dev failed: No such file or directory >> >> no fstab.sys, mounting internal defaults >> >> setuproot: error mounting /proc: No such file or directory >> >> setuproot: error mounting /sys: No such file or directory >> >> Switching to new root and running init. >> >> unmounting old /dev >> >> unmounting old /proc >> >> unmounting old /sys >> >> switchroot: mount failed: No such file or directory >> >> init used greatest stack depth: 4888 bytes left >> >> Kernel panic - not syncing: Attempted to kill init! >> >> Pid: 1, comm: init Not tainted 2.6.32.10 #2 >> >> Call Trace: >> >> [] panic+0xa5/0x167 >> >> [] ? xen_force_evtchn_callback+0xd/0xf >> >> [] ? _write_unlock_irq+0x30/0x3c >> >> [] ? trace_hardirqs_on_caller+0x110/0x134 >> >> [] ? trace_hardirqs_on+0xd/0xf >> >> [] ? _write_unlock_irq+0x37/0x3c >> >> [] do_exit+0x7e/0x701 >> >> [] sys_exit_group+0x0/0x1b >> >> [] sys_exit_group+0x17/0x1b >> >> [] system_call_fastpath+0x16/0x1b >> >> On Sat, Apr 17, 2010 at 5:22 AM, Pasi K=E4rkk=E4inen <[1]pasik@iki.= fi> wrote: >> >> On Fri, Apr 16, 2010 at 03:24:53PM -0700, kishore kumar wrote: >> > I am using my Dom 0 kernel to boot as my Dom U. >> > I edited /etc/xen/xmexample1 file and modified only below li= nes >> > >> > kernel=3D"/boot/vmlinux-2.6.32.10" >> > memory=3D512 >> > vcpus=3D5 >> > root =3D "/dev/VolGroup01/LogVol00 ro" >> > Below is the output I pasted after freezing. Not sure what = is >> wrong. Can >> > you please help me here?? >> > I doubt if I have provided the correct root option? >> > >> >> I bet that kernel has xen block frontend driver as a module? >> >> You don't seem to have ramdisk/initrd image, >> so you simply don't have the driver loaded at all >> to access the root disk in the guest. >> >> You must create an initrd image that loads the driver module in t= he >> guest. >> > >> > VFS: Cannot open root device "VolGroup01/LogVol00" or >> unknown-block(0,0) >> > >> > Please append a correct "root=3D" boot option; here are the = available >> > partitions: >> > >> > Kernel panic - not syncing: VFS: Unable to mount root fs on >> > unknown-block(0,0) >> > >> >> Root was not found - this is usually because you don't have the x= en >> blockdev frontend driver loaded. >> -- Pasi >> >> References >> >> Visible links >> 1. mailto:pasik@iki.fi >> =20 > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel > =20