Can we prefix this list?
Can you guys prefix the subject line of this list like other lists do? Would make managing/filtering this list into folders much easier. Example Subject: [grub-devel] Can we prefix this list? -- Shaun Reitan Network Data Center Host, Inc. ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
PV-Grub2 works here but doesnt work their...
I posted this to the Xen Mailing Lists too but figured i should post
here as well.
We are experiencing a odd issue after we built grub2 support. The image
we built works fine on some hosts and then just hangs on others.
I built grub2 as follows...
-
git clone http://git.savannah.gnu.org/cgit/grub.git
cd grub
wget http://prgmr.com/~srn/grub2/xen-linux16.patch
patch -p1 < xen-linux16.patch
./autogen.sh
./configure --target=x86_64 --with-platform=xen --prefix=/opt/grub2
make
make install
export PATH=/opt/grub2/bin:/opt/grub2/sbin:$PATH
Next I built the image as follows...
---
cat > grub-bootstrap.cfg << EOF
normal (memdisk)/grub.cfg
EOF
cat > grub.cfg << EOF
for grubcfg in /boot/grub2/grub.cfg /boot/grub2/grub2.cfg
/boot/grub/grub2.cfg /boot/grub/grub.cfg /grub2/grub2.cfg /grub/grub.cfg
/etc/grub2.cfg /etc/grub.cfg ; do
if search -s -f $grubcfg ; then
echo "Reading (${root}$grubcfg"
configfile $grubcfg
fi
done
EOF
tar cf memdisk.tar grub.cfg
/opt/grub2/bin/grub-mkimage -O x86_64-xen -c grub-bootstrap.cfg -m
memdisk.tar -o grub2-x86_64 /opt/grub2/lib/grub/x86_64-xen/*.mod
This works fine on some of our hosts, but then just seams to hang on
others. When starting the guest i see the following...
[root@devhostxxx ~]# xm create -c /home/username/vs.config
Using config file "/home/username/vs.config".
Started domain username (id=34)
[root@devhostxxx ~]#
Then it just hangs from their.
These hosts are CentOS 6 using the CentOS-Xen RPMS. Hosts are running
Xen version 4.4.1-8el6 and still using xend with xm commands
Any idea what may be going on here? Or how i should go about debugging
this issue?
--
Shaun___
Grub-devel mailing list
Grub-devel@gnu.org
https://lists.gnu.org/mailman/listinfo/grub-devel
grub2 + xen + lz4 kernels
I currently use XEN to boot PV (paravirt) virtual server instances for our customers. Grub2 introduced support for booting a xen kernel directly from a guests disk image which has worked great for years. We use the following command to build our image grub-mkstandalone -O x86_64-xen -o grub2-x86_64.gz boot/grub/grub.cfg What we have been seeing more and more is newer distros like Ubuntu 20.04 using lz4 compressed kernel images which will not boot and displays the error "not xen image." If i use the https://raw.githubusercontent.com/torvalds/linux/master/scripts/extract-vmlinux utility to decompress the kernel image I am able to boot it without any issues using our current grub2 xen loader. My question is how can I get lz4 support added into grub2 for xen? We are willing to pay for a dev to add this support if needed as I have limited time to really dig into this. There are a few workarounds out their, most involve a hook that decompresses the kernel after an update but I'm not wanting to add complexity to the kernel update process. It leaves too much room for error and the possibility of a clients server failing to boot after what should of been a simple kernel upgrade. Any help, even if just pointing me in the right direction would be appreciated! -- Shaun Reitan NDCHost.com ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
Re[2]: grub2 + xen + lz4 kernels
Hi Daniel thanks for your reply! You mentioned finding a new LZ4 library but grub2 already looks to support lz4 compressed kernels. The issue is that they don't look to be supported under the Xen platform with a target of x86_64. I'm going to poke around on this today and see what I can figure out. I was able to get this working by converting the domU to pvh but that has introduced a few new issues that will require changes to our back-end. -- Shaun Reitan NDCHost.com -- Original Message -- From: "Daniel Kiper" To: "Shaun Reitan" Cc: "Juergen Gross" ; grub-devel@gnu.org Sent: 11/30/2021 9:33:20 AM Subject: Re: grub2 + xen + lz4 kernels On Tue, Nov 30, 2021 at 07:21:42AM +0100, Juergen Gross via Grub-devel wrote: On 30.11.21 00:25, Shaun Reitan wrote: > I currently use XEN to boot PV (paravirt) virtual server instances for > our customers. Grub2 introduced support for booting a xen kernel > directly from a guests disk image which has worked great for years. We > use the following command to build our image > > grub-mkstandalone -O x86_64-xen -o grub2-x86_64.gz boot/grub/grub.cfg > > What we have been seeing more and more is newer distros like Ubuntu > 20.04 using lz4 compressed kernel images which will not boot and > displays the error "not xen image." > > If i use the https://raw.githubusercontent.com/torvalds/linux/master/scripts/extract-vmlinux <https://raw.githubusercontent.com/torvalds/linux/master/scripts/extract-vmlinux> utility > to decompress the kernel image I am able to boot it without any issues > using our current grub2 xen loader. > > My question is how can I get lz4 support added into grub2 for xen? We > are willing to pay for a dev to add this support if needed as I have > limited time to really dig into this. > > There are a few workarounds out their, most involve a hook that > decompresses the kernel after an update but I'm not wanting to add > complexity to the kernel update process. It leaves too much room for > error and the possibility of a clients server failing to boot after what > should of been a simple kernel upgrade. > > Any help, even if just pointing me in the right direction would be > appreciated! Hmm, Grub2 already supports some compression methods, so adding LZ4 shouldn't be that hard. Especially as there already is some LZ4 support hidden in the ZFS handling. I guess this LZ4 support wants to be put into a grub module of its own and then be added to the filter list. You should have a look at: - GRUB_FILE_FILTER_GZIO for an example how a compression filter is added via grub_file_filter_register() - the file grub-core/fs/zfs/zfs_lz4.c for current LZ4 support in Grub2 This should basically do the job. I've added Daniel to Cc: as he might have some more thoughts. Yeah, in general I agree. However, I would look for an LZ4 library which could be merged with the GRUB code, licensing compatibility is important here, and is under active development/maintenance. If there is no such we can reuse ZFS LZ4 code. Daniel ___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
Load grub from grub (XEN-PVH)
I run a Xen virtual environment of with PVH guests. I've built a grub2 image that loads the grub config from the guests disk so that grub can boot the correct kernel from that guests disk. This works great with distro's that use unmodified versions of grub2 but if I try to use a distro like CentOS 8 I run into problems because they look to have patched in something called blscfg and what ends up happening is I get the error /boot/grub/i386-xen_pvh/blscfg.mod not found. I'm curious if there is a way to build a grub2 PVH image that would load grub2, it's config and modules from the disk? -- Shaun R___ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
