varlink and the elvish shell

I recently discovered Elvish, which is a shell perfectly suited to process structured data. In my case it is perfect to be used with varlink. Too bad elvish has no numeric type and can’t feed varlink with int and float, because to-json converts them to strings. To see what I […]


varlink for dnf – a Showcase

On the varlink wiki page I showcase how to add varlink to a python project. In this case, I chose DNF, the rpm package manager of Fedora.


Varlink

Chicken and Egg For a long time we tried to solve the early boot IPC problem. IPC problem you ask? Well, in the early boot phase we cannot talk D-BUS, because the daemon is not running yet, but to bring up the system, so that the D-BUS daemon can run […]


Rust Echo Server

On modern CPUs, rust seems to perform very nicely with the thread context switches, at least when benchmarking an echo server. For that I also wrote an echo server benchmark client. The README.md of the server also contains some benchmark numbers.


dracut and CVE-2016-4484: Cryptsetup Initrd root Shell

People who want to secure their Fedora/RHEL system have to: add a BIOS password add a grub password add “rd.shell=0” to the kernel command line Anaconda does add “rd.shell=0” to the kernel command line automatically, if you setup the bootloader with a password.


GPG, Smartcard and ssh

This blog posts shows how to tweak Fedora, if you want to use a smartcard with OpenPGP and use it also as a ssh key. It also serves me as a recipe for fresh installations.


A Python Transaction Class

This is a repost of a blog post of 2008. Just for the reference 🙂 This class allows sub-classes to commit changes to an instance to a history, and rollback to previous states. The final class with an extension for __setstate__ and __getstate__ can be found here: transaction.py and transaction_test.py. […]


libtool: getting rid of 180,000 sed forks

When compiling systemd on rawhide, we noticed a significant slowdown in compile time. Investigating further, it turns out, that libtool forks an incredible amount of sed. Running perf showed 30% of the “make all” was spent in bash. strace showed an execve of sed with the same arguments 180,000 times!!!!! […]


Single UEFI executable for kernel+initrd+cmdline

Lately Kay Sievers and David Herrmann created a UEFI loader stub, which starts a linux kernel with an initrd and a kernel command line, which are COFF sections of the executable. This enables us to create single UEFI executable with a standard distribution kernel, a custom initrd and our own […]