On Tue, Dec 20, 2022 at 08:42:14PM +0100, Björn Persson wrote: > > Main motivation for this move is to make the distro more robust and more > > secure. > > Improving security would be great, but it must be done in a way that > allows the sysadmin to configure and repair the system and authorize > the new configuration. > > > Switching the whole distro over to unified kernels quickly is not > > realistic though. Too many features are depending on the current > > workflow with a host-specific initrd (and host-specific kernel command > > line), which is fundamentally incompatible with unified kernels where > > everybody will have the same initrd and command line. Thats why there > > is 'Phase 1' in title, so we can have more Phases in future releases > > 😃 > > Whew! So usable kernels won't go away in F38. I only have to worry > about being forced to build my own kernels in some unspecified future > phase. Doom is still coming but no one knows when. That's *such* a > relief. > > > A host-specific initrd / command line is needed today for: > [...] > > * configuration being specified on the kernel command line. > > ** root filesystem being the most important one. > > [https://systemd.io/DISCOVERABLE_PARTITIONS/ Discoverable partitions] > > allow to remove this. > > Why link to a page that only contains a link to another page? Why not > link directly to > https://uapi-group.org/specifications/specs/discoverable_partitions_specification/ > > That page makes it clear that omitting root= from the kernel command > line is only an *option* which is proposed only "for simpler, > appliance-like installations". My workstation and my laptop aren't > appliance-like in the slightest. And on appliances you want a stable, > reliable operating system, not a fast-moving, unstable one like Fedora. > > ** Troubleshooting being the second most important one. When the system > won't boot, it's necessary to remove "quiet" and "rhgb" from the kernel > command line to see how far the boot process gets and what error > messages are printed. It may also be necessary to configure a serial > console for example.
Current UKIs only support a single embedded cmdline, but I've proposed supporting multiple. The intent would be to ship with two cmdlines, one for "normal" production usage which would be 'quiet rhgb' and one for debug usage, which would omit 'quiet rhgb'. The bootloader would need to allow the user to pick between the two options, but this would allow SecureBoot to be sustained. > The root filesystem is also relevant for troubleshooting, when I take a > storage device out of a broken computer and connect it to another > computer to inspect it. Suddenly there are two "discoverable" root > partitions, and the kernel parameter is necessary to specify which one > is the root filesystem, as stated under "Doesn’t this break multi-boot > scenarios?": > https://uapi-group.org/specifications/specs/discoverable_partitions_specification/#doesnt-this-break-multi-boot-scenarios This proposal for UKIs is targetting VM usage where multi-boot is not something that is important. You can take the guest disk image and access it using tools like 'guestfish' to access data, and discoverable partitions won't make that aspect of it harder. Note that when systemd discovers partitions, it only discovers partitions on the same physical disk that the kernel is booting from. So even in the bare metal case, it wouldn't even consider the discoverable partitions on your second disk. The problems only arise if you have multiple OS installs on the same disk. > > Phase 2/3 goals (longer-term stuff which is not realistic to complete for > > F38). > > > > * Move away from using the kernel command line for configuration. > > I note that taking away the kernel command line is indeed a clearly > stated goal, which will limit Fedora to simple, appliance-like uses. That bullet point is a little open to mis-interpretation. If it is possible to do something on the kernel command line today, it isn't proposing to remove that ability. This point is rather about providing an alternative way to achieve the same goal without relying on the command line. IOW there would be a choice, with the right answer picked depending on the usage scenario. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| _______________________________________________ devel mailing list -- devel@lists.fedoraproject.org To unsubscribe send an email to devel-le...@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
