Hans van Kranenburg
2019-Jan-04 01:49 UTC
[Pkg-xen-devel] Now is the time! Help testing Xen for Buster.
Hi all, The Buster freeze is approaching at full speed! [0] Now is the time to start upgrading your test environments to Buster to see how they behave with Xen 4.11 and Linux 4.19. *1) I've been using these packages for months at work (at Mendix) successfully already, but that doesn't mean that all the (packaging) bugs which are lurking in the corner of your specific situation have been found yet. Especially full upgrade reports from Stretch to Buster are interesting, since there's quite some changes made in the packaging. Does it do the right thing? Is it convenient? Right now we can still change things, after the Buster release it will be much harder. So test and report now, instead of doing so after the release, when it's too late. While everything is in pretty good shape (especially after the packaging rewrite by Ian in September, yay), there are still a few issues which would be nice to improve. The first one, the init scripts one is the biggest, and if we want to make changes there, it should happen ASAP. ---- 8< ---- "Review init scripts in the package and see if we can drop modified old versions and use upstream ones." The init scripts that we currently ship are some old debian-baked ones, which are not the ones that are in the upstream source. While things seem to work (tm) this sounds a bit worrying. The task here would be to find out what the differences between the init script collections are, find out that (hopefully) the debian ones can be thrown in the trash can and be replaced with the upstream ones, and then test everything and also have it work properly with systemd. And, the stop/start init scripts need to deal with There are some related complaints about "warning: something called deprecated script /usr/lib/xen-common/bin/xen-toolstack" and confusing "[warn] Not running within Xen or no compatible utils ... (warning)." that could maybe be solved by this. ---- 8< ---- Command line tab completion doesn't work properly. Well, it does something, but it completes file paths, which doesn't make any sense: -# xen [TAB][TAB] .bash_aliases .bashrc .profile .vim/ .vimrc .bash_history .lesshst .ssh/ .viminfo I'd rather have it do nothing than this. The task here is to find out if we actually ship the right bash-completion files in the right place and if so, find out why they're not picked up. ---- 8< ---- pygrub is borken. See https://bugs.debian.org/912381 We either need to drop pygrub support or fix it. This one is probably best done by Ian, who touched all of this in september. ---- 8< ---- Have grub (dom0) do the right thing for booting with and without Xen. The new packaging contains some changes to input files for grub in /etc/default, which make it possible to have bit of a difference between linux kernel command line options when starting with and without Xen. E.g. console settings can be either ttyS0 or hvc0. I'm planning to look into this one myself, but don't hesitate to explore when interested. ---- 8< ---- For the Linux kernel part, there's an open issue with live migration [1] and there's also still an idea to provide better error reporting for the infamous max grant frames case where domUs stall without any proper error message for the user. The latter one will maybe happen later (adding hints which show up in dmesg) but not now. ---- 8< ---- Feel free to reply, and #debian-xen on OFTC IRC is of course also available for a chat (I'm Knorrie). Thanks, Hans [0] https://release.debian.org/buster/freeze_policy.html [1] https://lists.xenproject.org/archives/html/xen-devel/2018-12/msg02167.html *1) I'm using stretch-backports packages of both Xen and the Linux kernel that I make myself and use them on Stretch dom0s. The stretch-backports for Linux 4.19 will be available soon, and if you don't need to boot PVH with grub, the current ones are also ok. If anyone wants to use Xen 4.11 (without qemu/HVM) on stretch and doesn't know how to do that, just ask me.