Posts

Latest Posts

Rocky Linux 9.2 is rocky


Although Rocky Linux 9.2 emerged on Tuesday, one of the architectures wasn't ppc64le - the release was held back. This seems to be due to a Power-specific bug in the provided build of Python 3.9, and also affects RHEL 9.2 (but not, near as I can tell, Fedora 38, which ships with Python 3.11 and runs fine on my systems). There are also no build artifacts available and there is currently no ETA for repair. Because Rocky Linux's mirrorlist can't hold back just one architecture, you'll need to add --releasever 9.1 (or change /etc/dnf/vars/releasever) to ensure dnf update doesn't get polluted with later metadata until the revised architecture spin is available.

Firefox 113 on POWER


Yes, I skipped a version, sosumi. I'm running a little low on development space on the NVMe drive, but still managed to squeeze in Firefox 113 which introduces enhanced video Picture-in-Picture, more secure private windows and password generation, support for AVIS images, debugger improvements and additional CSS and API features. As usual you'll need to deal with bug 1775202 either with this patch — but without the line containing desktop_capture/desktop_capture_gn, since that's long gone — or put --disable-webrtc in your .mozconfig if you don't need WebRTC. The browser otherwise builds and works with the PGO-LTO patch for Firefox 110 and the .mozconfigs from Firefox 105.

Fedora 38 mini-review on the Blackbird and Talos II


This article would have come out sooner except I also wanted to test building Firefox in Fedora 38, and then when I tried to run libnxz/power-gzip to test out the POWER9 nest accelerator make check made my daily driver Talos II machine check and caused Hostboot to guard out the entire CPU with the NVMe drives attached (and fixing that caused Petitboot to barf on a stuck XFS log entry again, requiring a trip to the Blackbird to mount and repair it). But here we are.

As I always say in these mini-reviews, 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 usual, recall both my T2 and Blackbird are configured to come up in a text boot instead of gdm and I start KDE manually from there. I still test GNOME on both systems, but I've pretty much entirely migrated over to KDE Plasma, and you should never have considered my GNOME testing to be exhaustive anyway. I strongly recommend a non-graphical boot as a recovery mechanism in case your graphics card gets whacked by something or other. On Fedora this is easily done by ensuring the symlink /etc/systemd/system/default.target points to /lib/systemd/system/multi-user.target.

Because of issues with dnf kernel updates still sometimes not updating the grub config (basically bug 1921479, showing messages like 0ed84c0-p94177c1: integer expression expected during the process), I've added a little extra paranoia to the usual install dance. To wit:

dnf upgrade --refresh # upgrade prior system and DNF
grub2-mkconfig -o /boot/grub2/grub2.cfg # force grub to update
dnf install dnf-plugin-system-upgrade # install upgrade plugin if not already done
dnf system-upgrade download --refresh --releasever=38 # download F38 packages
dnf system-upgrade reboot # reboot into upgrader

This went fairly smoothly on both systems. Other than a copr package with a stale prerequisite I had to remove, there were no issues or conflicts with the 38 packages. As long as you manually select the new kernel in Petitboot before the system starts, you'll get some sort of installation screen. On the Blackbird's HDMI output from the ASPEED BMC framebuffer, the same friendly GUI installer will appear as in prior releases:

But even without using BMC video, like on the T2 with the Raptor-BTO WX7100 workstation card, as before you'll still get to see the install log live as text (which by now I've found more useful anyway). If you forget to manually select the kernel and the system comes up to an apparently black screen, you can either monitor on the serial port, or from a connected system viewing the serial console over the BMC's web server, or by logging into another VTY with CTRL-ALT-F2 or as appropriate as root and periodically issuing dnf system-upgrade log --number=-1 to watch log updates.

The update did not cause a stuck XFS log entry this time on either the Blackbird or the T2, but after the reboot I did need to do one more grub2-mkconfig -o /boot/grub2/grub2.cfg and a restart to ensure the right kernel and version were being used. Currently the kernel version as of this writing is 6.2.14.

Our first stop on the BMC-only Blackbird is GNOME on Wayland, started (awkwardly) with XDG_SESSION_TYPE=wayland /usr/libexec/gnome-session-binary --builtin. This configuration hasn't visibly improved any from Fedora 37; there are still prominent artifacts moving windows around and display through the HDMI adapter is still limited to 1024x768.

Performance wasn't hideous but the artifacts were distracting. I couldn't get a screenshot of it in Spectacle so I just grabbed a picture on my Pixel 7 Pro. However, the story isn't a whole lot better in GNOME on X11:
While we now have a full 1920x1020, you can see that the title bar still isn't being painted correctly. This occurred with most of the applications I tried. I consider this a critical fault due to the smearing, so I can't really recommend GNOME at all under any window system if you're using baseline BMC graphics. And KDE?
Well, it works fine. I use KDE on the T2, so now I'm using it on the Blackbird as well. If you really prefer a Gtk default, Xfce should also serve you well.

On the T2 with its AMD GPU, however, I dumped GNOME because of libadwaita encroaching on my customizations; even my shell theme has stopped working now. But the basics are fine: there are no more obvious problems with CTM, and performance seems similar to 37 with no obvious issues in Wayland or X11. On KDE, my customizations persisted without having to rework any of them, which is why I've converted fully over to KDE.

Overall, the F38 update was smooth and it runs pretty much like F37. If you had no problems with F37, you'll probably have no problems with this; you just won't see much improvement in some of the longstanding annoyances either.

Fedora 38


Fedora 38 is out — a week early, for a change. Fedora matters to us here at Orbiting Floodgap HQ because it's what we run on our Talos II and Blackbird systems and it should matter to you because, being a bleeding edge distro, changes occur there first that tricke down to other distributions. That's why we make efforts to do mini-reviews of each release. With F38's release F36 will be End of Life in one month.

The changeset for 38 is typically extensive. Possibly the most controversial was the change to globally build with -fno-omit-frame-pointer to facilitate better profiling and debugging, particularly where debugging information is not available, but at a cost as this also takes a register out of circulation to hold the frame pointer. The performance impact seems to be limited on x86_64 but I doubt much testing was done on ppc64le, and it should be noted that PowerPC is one of the gcc targets where leaf functions wouldn't use a frame pointer anyway. Time will tell if this pays off. Builds are also now made with _FORTIFY_SOURCE=3 (up from 2) for better security, and another interesting though probably irrelevant change for most is reducing the shutdown timer in systemd to 45 seconds from 2 minutes.

On the back-end F38 ships with kernel 6.2.x and gcc 13, LLVM 16, gmake 4.4, binutils 2.39, glibc 2.37 and gdb 12.1. F38 also has a major upgrade to microdnf as dnf5, the "future of package management" that may ultimately replace dnf entirely. On the front-end F38 updates GNOME to version 44, finally with grid thumbnail view in the file picker, a big overhaul to the Settings app and many new applications, as well as more apps moving to the unthemable libadwaita (but I run KDE Plasma now, and haven't looked back). Xfce also updates to 4.18, there's a new spin for the Sway window manager, and the SDDM display manager now also defaults to Wayland (we use a text boot to log in and start X11 manually, avoiding any display manager completely).

This is the first release to include the change that blocks clients with different endianness from connecting to the X server, including XWayland, which means that the compositor has to support the configurable option too (GNOME 44 Mutter does, others may not). At least you still have the option!

We'll give the mirrors a week or two to catch up on builds and then start the transition on our own machines, with the usual mini-review to follow. Stay tuned.

FreeBSD 13.2


And hot on the heels of the latest OpenBSD release is the latest FreeBSD iteration, 13.2-RELEASE. FreeBSD has a longer track record on OpenPOWER and in my cursory estimates is the most commonly installed BSD on modern Power ISA. One big jump is that the bhyve hypervisor now supports more than 16 virtual CPUs and by default can create the same number of vCPUs as physical CPUs, which is quite useful to us once you get away from the smallest single-4 machines given all our cores are SMT-4. Additionally, for those of you running FreeBSD on a VM (such as an LPAR or under KVM), nested POWER9 radix MMU mappings are now supported on the pseries flavour, substantially reducing hypercall overhead. The Linux compatibility ABI has also been expanded and on the security side ASLR is now enabled for all 64-bit executables by default, configurable through proccontrol. Downloads are available for big-endian and little-endian. Note that the release notes indicate that all PowerPC and Power ISA releases right now must run kldxref /boot/kernel manually after an upgraded successful kernel and world installation.

OpenBSD 7.3


OpenBSD 7.3 is released. While most of the improvements are not specific to Power ISA, there's a lot we benefit from, including many kernel calls which are now "lock-free" (improving SMP performance) like mmap(2) and select(2), more device support, immutable permissions on address ranges to prevent permissions from being changed in the future — much of a running program's static address space like stack, code and most libraries is now automatically immutable — and support for execute-only memory on both Power ISA and the PowerPC 970 ("G5"). LibreSSL is updated to 3.7.2, OpenSSH is updated to 9.3, and the OS ships with LLVM/clang 13.0.0 and Perl 5.36.0. Download and install when ready, Puffy.