Fedora 41 mini-review on the Blackbird and Talos II

It's Fedora upgrade time again! And in the same way I preface all these mini-reviews (see our last for Fedora 40), Fedora was one of the first mainstream distributions to support POWER9 out of the box, it's still one of the top distributions OpenPOWER denizens use and its position closest to the bleeding, ragged edge is where we see problems emerge first and get fixed (hopefully) before they move further downstream. That's why it's worth caring about it even if you yourself don't run it. Also, as always, recall both my Talos II and Blackbird are configured to come up in a text boot instead of gdm and I start the GUI manually from there. I always recommend a non-graphical boot as a recovery mechanism in case your graphics card gets whacked by something or other, and on Fedora this is easily done by ensuring the symlink /etc/systemd/system/default.target points to /lib/systemd/system/multi-user.target.

I'll also give a quick shout out here to Dan Horák at Red Hat, who responds to our user issues and maintains some additional Fedora packages in copr. Read his newly updated blog for information.

Irritatingly, dnf continues to fail to update grub2's config (bug 1921479, showing messages like 0ed84c0-p94177c1: integer expression expected during the process), so the process remains largely unchanged from F39 and F40:

dnf upgrade --refresh # upgrade prior system and DNF
grub2-mkconfig -o /boot/grub2/grub.cfg # force grub to update
dnf install dnf-plugin-system-upgrade # install upgrade plugin if not already done
dnf system-upgrade download --refresh --releasever=41 # download F41 packages
dnf system-upgrade reboot # reboot into upgrader

Again there was no installation screen on either the Blackbird or T2 this time around; for both systems I needed to log in as root on an alternate VTY (Ctrl-Alt-F2 or as appropriate) and either dnf system-upgrade log --number=-1 intermittently to watch the updates, or just do journalctl -f if you want a live feed and don't mind the scrollspam. You can probably also still monitor it on the virtual TTY in the BMC web interface. Both systems then rebooted (fast reboot is disabled on both) and came up clean, again with no XFS burp on the T2! I think we can conclude the updated Petitboot firmware has resolved that issue. As usual, one more grub2-mkconfig -o /boot/grub2/grub.cfg was needed to get Petitboot's menu looking right and the install was complete.

I should also note that two people on the Raptor forums reported that their systems were unbootable after this update. However, both the Blackbird and the T2 upgraded with no hitches except for a really old F33 package on the T2 I had to blow away, so I can't replicate that here and neither can Dan.

Let's proceed with testing out the Blackbird, which is my proving ground system before upgrading my regular T2 workstation. The biggest update is that in the most recent kernel versions, especially if you haven't done any updates between the F40 upgrade and now, we finally have 1920x1200 support on the built-in BMC HDMI video!

Yes, much as it pains me to say it, Wayland has finally progressed to the point where it's useable with the ASPEED BMC framebuffer. This is a crucial point to make if you're running a GPU-less configuration, especially if you're trying to achieve a fully libre machine with no firmware blobs: you can now use Wayland with it with little obvious compromise, if you really really want.

All resolutions up to 1920x1200 are supported, including 1920x1080. This works in both GNOME and KDE Plasma 6.2, though I'll have something bad to say about GNOME in a moment.

Now, there's still reasons not to use Wayland with BMC graphics, and the big one is that the fans just ran continuously in Wayland because everything is getting crammed through llvmpipe. This is a little 4-core Blackbird and it could keep up with it, but it certainly earned its money doing so. When I switched back to Xorg using plasma6-x11-unsupported, all was quiet again.

X11 modelines never had any problems supporting BMC video, but here it is for the record.

I also commented on the Chromium build now available for ppc64le in the F40 mini-review, so it's only fair to see how far it's come. And, well, it's come a long way. Many more things work and the previous graphical glitches in Xorg seem gone now. It's still somewhat rickety and crash reports pop up intermittently as its subprocesses fart and die, and really big Wasm apps like (oh the irony) Google Earth will bring it to its knees, but casual browsing largely works fine and it can run MAME from the Internet Archive's online arcade now with reasonable performance. I still find my personal builds of Firefox with Baseline JIT to be faster with browsing and I retain my philosophical objections to Chrome and Chromium, but I can't deny the progress, so this will make others of you happy.

Something that won't make you happy was GNOME. Whether it was Wayland or Xorg, there were tons of graphical artifacts on the blob-free Blackbird (these are photographs of the screen since the framebuffer didn't always reflect the issue):

The Plasma 6.2 update doesn't seem to break anything major, so if you're blob-free, I'd just use KDE with the unsupported X11 support. It's easier on the cores and it generally works. Xfce would probably be okay too.

On the T2, other than that weir-dass F33 remainder package, the upgrade was similarly smooth. Nothing so far has seemed to regress. However, the Talos II has a Raptor-BTO AMD WX7100 card, unlike the Blackbird.

Regular readers know very well I'll complain when it's time to complain, but this time around the F41 upgrade worked well and the system seems solid. I'm sorry to hear about the problems some others have had, but I couldn't replicate them here. So far this has been one of the smoother updates, which was a profound relief.

CHRP support gone from Linux kernel

UPDATE: The patch has been retracted, see comments.

There weren't that many Common Hardware Reference Platform PowerPC systems anyway, but if you have one of them (notably systems like IBM's RS/6000 7046 Model B50, the Total Impact briQ, Motorola PowerStacks or the PegasosPPC or Pegasos II from Genesi), your days are numbered as CHRP support will be removed from the next Linux kernel release. CHRP never got much market traction; Apple, then the largest seller of PowerPC machines, only partially supported it (Old World Macs are sui generis and New World Macs are a combination of CHRP and PReP), and as a result Linux support for Power Macs — at least what remains — never completely depended on it.

At least for the Genesi machines, however, you have better and more supported options in MorphOS and AmigaOS 4, and while Power Macs should still work, they're (IMHO) more usefully served by one of the BSDs. For the real oddball machines, though, if you were running a bleeding-edge kernel this is the end of the line — unless you'd like to step in and maintain it.

Updated Baseline JIT OpenPOWER patches for Firefox 128ESR

I updated the Baseline JIT patches to apply against Firefox 128ESR, though if you use the Mercurial rebase extension (and you should), it will rebase automatically and only one file had to be merged — which it did for me also. Nevertheless, everything is up to date against tip again, and this patchset works fine for both Firefox and Thunderbird. I kept the fix for bug 1912623 because I think Mozilla's fix in bug 1909204 is wrong (or at least suboptimal) and this is faster on systems without working Wasm. Speaking of, I need to get back into porting rr to ppc64le so I can solve those startup crashes.

Fedora 41

Just a quick note that Fedora 41 is out, the standard Linux distro we use here on our two Raptor systems. Based on kernel 6.11, he big updates are updated packaging with DNF 5 and RPM 4.20 plus Perl 5.40, Python 3.13, LLVM 19 and gcc 14.1/glibc 2.40. Fortunately there are apparently still optional Xorg support packages for GNOME and KDE Plasma. Once the package repos have stabilized a bit, I'll have the usual minireview. For now, refresh your memory with how things went with Fedora 40, and of course Fedora 38 will be EOL in about a month based on their standard schedule.