From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richie Subject: Re: /etc/grub.d/09-xen for generating grub.cfg for hypervisor boot entries. Date: Tue, 18 May 2010 20:24:11 -0400 Message-ID: <4BF32FAB.7050900@triad.rr.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Bruce Edge Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org I like the idea myself and I haven't seen anything in the wiki's other than manual creation steps. Just an opinion here, but why not use "dummy=dummy" as opposed to first parameter duplication? My understanding is that dummy is used to avoid this same bug. Either way we it avoids having to hardcode root= into the kernel cmdline .config parameter :) I don't know if parameter duplication would break things when the bug is fixed or not, but the dummy parameter shouldn't. I also think it might be viewed as something more familiar, perhaps self explanatory, whereas the parameter duplication may cause confusion. I skimmed the code and have not tested it. I don't see that it is specifically trying to ensure that the kernel is Xenlinux or pvops... Not that I know of a proper way to do such or if its even pratical. Aren't most kernels now pvops (thus bootable under xen) but not necessarily dom0 capable? I think a spin on this would be if one wanted to limit the Xen entries to kernels with "xen" (ie. --append-to-version) in the name. Perhaps the code would change as follows? list=`for i in /boot/vmlinu[xz]-*xen* /vmlinu[xz]-*xen* ; do if grub_file_is_not_garbage "$i" ; then echo -n "$i " ; fi done` Bruce Edge wrote: > If this has already been done, please forgive me. However, if not, I'd > like to submit this as a mechanism for generating a bootable grub2 > stanza for hypervisors. > > As the /etc/grub.d/* files rely on defaults in /etc/default/grub, I > added the following Xen specific variable: > > GRUB_CMDLINE_XEN_DEFAULT="console=com1 115200,8n1 dom0_mem=512M > dom0_max_vcpus=1 dom0_vcpus_pin=true iommu=1,passthrough,no-intremap > loglvl=all loglvl_guest=all loglevl=10 debug acpi=force apic=on > apic_verbosity=verbose numa=on" > > The script itself is a hacked version of the10-linux that comes with > grub2. This is 09-xen so it places it's boot entries ahead of the > non-xen entries. > The resulting grub.cfg entry looks like: > > ### BEGIN /etc/grub.d/09_xen ### > insmod lvm > set root=(system-dom0_0) > menuentry "Xen osa-dom0 6.0.13-05, linux 2.6.32.12" { > multiboot /boot/xen.gz /boot/xen.gz console=com1 115200,8n1 > dom0_mem=512M dom0_max_vcpus=1 dom0_vcpus_pin=true > iommu=1,passthrough,no-intremap loglvl=all loglvl_guest=all loglevl=10 > debug acpi=force apic=on apic_verbosity=verbose numa=on > module /boot/vmlinuz-2.6.32.12 /boot/vmlinuz-2.6.32.12 > root=UUID=a3764d7d-6292-4f08-8ece-480e54c77229 ro earlyprintk=xen > loglevel=10 debug acpi=force console=hvc0,115200n8 > module /boot/initrd.img-2.6.32.12 /boot/initrd.img-2.6.32.12 > } > ### END /etc/grub.d/09_xen ### > > Note the duplication of the first params. I believe there's a bug that > drops the 1st param so this could be changed later. > > #! /bin/sh -e > > prefix=/usr > exec_prefix=${prefix} > libdir=${exec_prefix}/lib > . ${libdir}/grub/update-grub_lib > > if [ "x${GRUB_DISTRIBUTOR}" = "x" ] ; then > OS=GNU/Linux > else > OS="${GRUB_DISTRIBUTOR}" > fi > > # Source grub defaults > . /etc/default/grub > > # loop-AES arranges things so that /dev/loop/X can be our root device, but > # the initrds that Linux uses don't like that. > case ${GRUB_DEVICE} in > /dev/loop/*|/dev/loop[0-9]) > GRUB_DEVICE=`losetup ${GRUB_DEVICE} | sed -e > "s/^[^(]*(\([^)]\+\)).*/\1/"` > ;; > esac > > if [ "x${GRUB_DEVICE_UUID}" = "x" ] || [ "x${GRUB_DISABLE_LINUX_UUID}" > = "xtrue" ] \ > || ! test -e "/dev/disk/by-uuid/${GRUB_DEVICE_UUID}" ; then > LINUX_ROOT_DEVICE=${GRUB_DEVICE} > else > LINUX_ROOT_DEVICE=UUID=${GRUB_DEVICE_UUID} > fi > > test_gt () > { > local a=`echo $1 | sed -e > "s,.*/vmlinu[zx]-,,g;s/[._-]\(pre\|rc\|test\|git\|old\)/~\1/g"` > local b=`echo $2 | sed -e > "s,.*/vmlinu[zx]-,,g;s/[._-]\(pre\|rc\|test\|git\|old\)/~\1/g"` > if [ "x$b" = "x" ] ; then > return 0 > fi > dpkg --compare-versions "$a" gt "$b" > return $? > } > > find_latest () > { > local a="" > for i in $@ ; do > if test_gt "$i" "$a" ; then > a="$i" > fi > done > echo "$a" > } > > list=`for i in /boot/vmlinu[xz]-* /vmlinu[xz]-* ; do > if grub_file_is_not_garbage "$i" ; then echo -n "$i " ; fi > done` > > while [ "x$list" != "x" ] ; do > linux=`find_latest $list` > echo "Found linux image: $linux" >&2 > basename=`basename $linux` > dirname=`dirname $linux` > rel_dirname=`make_system_path_relative_to_its_root $dirname` > version=`echo $basename | sed -e "s,^[^0-9]*-,,g"` > alt_version=`echo $version | sed -e "s,\.old$,,g"` > linux_root_device_thisversion="${LINUX_ROOT_DEVICE}" > > initrd= > for i in "initrd.img-${version}" "initrd-${version}.img" \ > "initrd.img-${alt_version}" "initrd-${alt_version}.img"; do > if test -e "${dirname}/${i}" ; then > initrd="$i" > break > fi > done > if test -n "${initrd}" ; then > echo "Found initrd image: ${dirname}/${initrd}" >&2 > else > # "UUID=" magic is parsed by initrds. Since there's no initrd, it > can't work here. > linux_root_device_thisversion=${GRUB_DEVICE} > fi > > cat << EOF > insmod lvm > set root=(system-dom0_0) > menuentry "Xen ${OS}, linux ${version}" { > multiboot /boot/xen.gz /boot/xen.gz $GRUB_CMDLINE_XEN_DEFAULT > module ${rel_dirname}/${basename} ${rel_dirname}/${basename} > root=${linux_root_device_thisversion} $GRUB_CMDLINE_LINUX_DEFAULT > EOF > if test -n "${initrd}" ; then > cat << EOF > module ${rel_dirname}/${initrd} ${rel_dirname}/${initrd} > EOF > fi > cat << EOF > } > EOF > > list=`echo $list | tr ' ' '\n' | grep -vx $linux | tr '\n' ' '` > done > > > -Bruce > ------------------------------------------------------------------------ > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel >