@pid_eins@mastodon.social
@pid_eins@mastodon.social avatar

pid_eins

@pid_eins@mastodon.social

⛵ I write software. ⛵

This profile is from a federated server and may be incomplete. Browse more on the original instance.

pid_eins, to random
@pid_eins@mastodon.social avatar

5️⃣ Here's the 5th installment of my series of posts highlighting key new features of the upcoming v256 release of systemd.

I am pretty sure all of you are well aware of the venerable "sudo" tool that is a key component of most Linux distributions since a long time. At the surface it's a tool that allows an unprivileged user to acquire privileges temporarily, from within their existing login sessions, for just one command, or maybe for a subshell.

"sudo" is very very useful, as it…

pid_eins,
@pid_eins@mastodon.social avatar

@zeld and i mean taking at face value what you circled in red: the whole of systemd, with all its many many components, including the systemd-run tool (which is run0 under a different name) and things only has a bit more than double the cves assigned than sudo. Man, we must be doing a hell of a good job then...

Learn to interpret statistics properly, man.

pid_eins, to random
@pid_eins@mastodon.social avatar

Now to one of the big questions of our times: what's better style? open("…", O_DIRECTORY|O_RDONLY|O_CLOEXEC) or open("…", O_DIRECTORY|O_CLOEXEC)?

Of course, both are entirely equivalent, because O_RDONLY on Linux is 0. But on a philosophical, conceptual level, what's the better way to write this?

(Asking because half of the systemd codebase does it one way, the other does it the other way.)

This is your time to shine, and contribute to the major philosophical discussion of today!

pid_eins, to random
@pid_eins@mastodon.social avatar

Regular reminder that we maintain a kernel API wishlist here:

https://uapi-group.org/kernel-features/

It gains new requests all the time (scroll to the bottom), and we even managed to cross some items of the list already.

pid_eins, to random
@pid_eins@mastodon.social avatar

Here's a fun new feature we are working on in systemd: userspace-only reboot. In order to reduce grey-out times on image-based OS updates to next to nothing we are making a reboot happen where kernel stays as it is, but userspace shuts down as usual, then possibly transitions into a new rootfs, and starts up again with an initial transaction as it would on a classic system boot. During the transition selected services can pass along their fds and listening sockets, to pass "live" resources…

pid_eins, to random
@pid_eins@mastodon.social avatar

1️⃣2️⃣ Here's the 12th installment of posts highlighting key new features of the upcoming v256 release of systemd.

Putting a PC to sleep is complicated business and there are different mechanisms available to achieve this on Linux. Broadly speaking there is suspend-to-ram and suspend-to-disk, as well as combinations of this: one where we suspend to both, and one where we first suspend-to-ram and then later change to suspend-to-disk, if we have slept for a long time, or the battery is running empty.

pid_eins, to random
@pid_eins@mastodon.social avatar

1️⃣5️⃣ Here's the 15th installment of posts highlighting key new features of the upcoming v256 release of systemd.

systemd integrates with many components of the OS. Due to this it links against various external libraries. Generic distributions – which typically enable all features a package provides – usually have to deal with relatively large dependency trees in cases like this.

pid_eins, to random
@pid_eins@mastodon.social avatar

Seems its that season of the year again, where I get to populate my blocklists of assholes on the Internet.

Good to get a personal refresher on how the wider audience on the Internet behaves. 🤮

pid_eins, to random
@pid_eins@mastodon.social avatar

Reminder: we maintain a kernel feature wishlist here as part of the uapi group:

https://github.com/uapi-group/kernel-features

I just added a bunch of new entries to it (at the bottom). If you are looking for something to hack on (and have some kernel expertise, or would like to acquire it), would be more than excellent to work on those!

pid_eins, to random
@pid_eins@mastodon.social avatar

Even though Fedora probably is kinda popular among developers, it sometimes baffles me what is and what isn't packaged in Fedora.

I mean come on, how is it possible that there's no meson mode packaged for emacs on Fedora?

I mean, it's pretty obvious: if Fedora wants to be taken seriously as a developer platform, I think it's pretty obvious that this is a glaring omission, like no other! 🤓

pid_eins, to random
@pid_eins@mastodon.social avatar

Busy at the Image-Based Linux Summit, Berlin!

pid_eins, to random
@pid_eins@mastodon.social avatar

Credit where credit is due! I'd really like to take a minute and thank Jia Tan how they helped us to finally get sd_notify() support merged into OpenSSH upstream!

https://bugzilla.mindrot.org/show_bug.cgi?id=2641

Thank you, Jia, you rock!

pid_eins, to random
@pid_eins@mastodon.social avatar

The excellent CCC VOC people published the AllSystemsGo! videos from this week. Here's the UKI talk I did there:

https://media.ccc.de/v/all-systems-go-2023-185-unified-kernel-images-ukis-

Enjoy!

pid_eins, to random
@pid_eins@mastodon.social avatar

Woohoo, we just released systemd v255-rc1:

https://github.com/systemd/systemd/releases/tag/v255-rc1

What an awesome release!

pid_eins, to random
@pid_eins@mastodon.social avatar

We recently added a new document to the systemd website focussing on one specific facet of the service manager: the fdstore. A concept that people should really use more to facilitate "seamless" service restarts and various other things. Please have a look:

https://systemd.io/FILE_DESCRIPTOR_STORE/

pid_eins, to random
@pid_eins@mastodon.social avatar

Lazy mastodon: anyone knows if we can enumerate passed virtiofs instances (by tag) from inside a VM userspace?

(Asking because we are pondering to add systemd-virtiofs-generator which will automatically mount virtiofs tagged by some scheme to certain dirs to simplify things)

virtiofs certainly appears as a device in sysfs when enabled, but I am a bit puzzled whether there's any scheme to enum the passed devices from userspace. (the kernel keeps a linked list of them afaics, but userspace?)

pid_eins, to random
@pid_eins@mastodon.social avatar

LWN just posted @bluca's summary of the image-base Linux summit in Berlin. Enjoy:

https://lwn.net/SubscriberLink/946526/a1c7bb28c62c9667/

pid_eins, to random
@pid_eins@mastodon.social avatar

PSA: Thou shalt not write udev rules with ACTION="add|change". Thou shalt use ACTION!="remove" instead.

If you look for "positive" events (i.e. that the device is present when it happens) then this is what you have to do. Why does this matter? Various kernel subsystems nowadays issue additional action event types (bind, unbind, …) that fire as part of device bring-up (usb…), and if your rule doesn't match on those the effect of your rules will likely be undone as these new actions are fired.

pid_eins, to random
@pid_eins@mastodon.social avatar

Are you coming to FOSDEM? There are a bunch of systemd and systemd adjacent talks at the conference (including two of yours truly). Make sure to attend these:

https://fosdem.org/2024/schedule/event/fosdem-2024-1987-systemd-boot-systemd-stub-ukis/
https://fosdem.org/2024/schedule/event/fosdem-2024-3309-kernel-command-line-to-configure-userspace-considered-harmful/
https://fosdem.org/2024/schedule/event/fosdem-2024-3282-soft-reboot-keep-your-containers-running-while-your-image-based-linux-host-gets-updated/
https://fosdem.org/2024/schedule/event/fosdem-2024-1985-ukis-tpms-immutable-initrds-and-full-disk-encryption-what-distributions-should-keep-in-mind-when-hopping-onto-the-system-integrity-train/
https://fosdem.org/2024/schedule/event/fosdem-2024-2888-mkosi-initrd-building-initrds-out-of-distribution-packages/
https://fosdem.org/2024/schedule/event/fosdem-2024-2024-uki-addons-and-extensions-safely-extending-ukis-kernel-command-line-and-initrd/

Hope to see you there!

pid_eins, to random
@pid_eins@mastodon.social avatar

Quiz: How many inode types are there on Linux?

You might think the answer to this is 7, i.e. regular files, directories, symlinks, block device nodes, char device nodes, fifos, and sockets. But you are actually are wrong: there's an 8th one. There's the concept of an anonymous inode on Linux which has the file type of zero. You can easily acquire fds to inodes of this type via eventfd(). If you call fstat() on such fds, then (.st_mode & S_IFMT) == 0 will hold. 🤯

pid_eins, to random
@pid_eins@mastodon.social avatar

Kernel breaking userspace episode nr. 43858262:

https://github.com/torvalds/linux/commit/a1912f712188291f9d7d434fba155461f1ebef66

Hacking around it:

https://github.com/systemd/systemd/pull/32892

pid_eins, to random
@pid_eins@mastodon.social avatar

Exciting: → https://blogs.gnome.org/alatiera/2023/08/04/developing-gnome-os-systemd-sysext/

pid_eins, to random
@pid_eins@mastodon.social avatar

Look at this:

https://blogs.gnome.org/chergert/2024/05/07/system-extensions-from-flatpak/

Love it! 👌

pid_eins, to random
@pid_eins@mastodon.social avatar

Can't wait for Wednesday, for AllSystemsGo! 2023. So many exciting talks! Have a peek at the schedule:

https://cfp.all-systems-go.io/all-systems-go-2023/schedule/

pid_eins, to random
@pid_eins@mastodon.social avatar

@grawity actually i tell people usually to just implement the proto on their own, its trivial and documented. In particular non-C projects really should use something native rather than wrap libsystemd.

Interestingly, libsystemd in git main doesn't pull in liblzma anymore, as we turned all compression deps into dlopen ones.

Also note that libselinux also pulls in liblzma and libselinux is pulled in by about everything... In particular via libpam.

pid_eins, to random
@pid_eins@mastodon.social avatar

I must say, I enjoy the picture of Vienna very much, that is on the Linux Plumbers Conference page at the top. Any people from Salzburg around, who wouldn't agree with that?

I mean, Vienna or Salzburg – doesn't really matter, right, the important thing is: Bavaria, amirite? ;-)

  • All
  • Subscribed
  • Moderated
  • Favorites
  • •
  • provamag3
  • mdbf
  • ngwrru68w68
  • modclub
  • magazineikmin
  • thenastyranch
  • rosin
  • khanakhh
  • InstantRegret
  • Youngstown
  • slotface
  • Durango
  • kavyap
  • DreamBathrooms
  • JUstTest
  • GTA5RPClips
  • ethstaker
  • normalnudes
  • tester
  • osvaldo12
  • everett
  • cubers
  • tacticalgear
  • anitta
  • megavids
  • Leos
  • cisconetworking
  • lostlight
  • All magazines
    •