Lukas

Full-stack engineer from solder to Gtk

GitHub: https://github.com/carrotIndustries
Languages: de, en, C++
pronouns: he\they
ECCN: EAR99

Last Notes

2026-03-03 20:08:17 UTC

Zu schade, dass der 40C3 nicht auf dem Messegelände Hannover stattfindet, sonst hätte man das Event CCCeBIT nennen können.
https://assets.chaos.social/media_attachments/files/116/167/044/542/900/297/original/dd1863f3e59e457a.png

2026-02-06 16:11:15 UTC

- reply

Looking at the changelog for 6.17.3, https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9c328f54741bd5465ca1dc717c84c04242fac2e1 was the only thing related to NFC.
Reverting this commit on the sources of the running kernel 6.18.7 and loading the patched module made NFC work again!
So it was time for my first mail to LKML: https://lore.kernel.org/lkml/[email protected]/T/#u
Let's see where this'll go.
🧵 3/3

2026-02-06 16:10:55 UTC

- reply

Being a hardware person, I did the obvious next thing an checked that the NFC waves are emanating from the touchpad which was the case. Tags however didn't react all, probably due to missing interrogation signal.
Running out of ideas, I downgraded the kernel back to the version I was running back when I got NFC to work.
Lo and behold, nfctool was detecting tags! After manually bisecting arch kernel versions, I found that NFC stoppend working from 6.17.2 to 6.17.3.
🧵 2/3
https://assets.chaos.social/media_attachments/files/116/024/556/825/652/667/original/e7ac6e9dd3ed6eaf.jpg

2026-02-06 16:10:10 UTC

- reply

The story doesn't end here. After a comment on the Arch Wiki, I tried NFC again and it didn't work anymore to the point that nfc0 was gone. After staring at the DSDT and sysfs for half an evening and subsequently wondering why NFC was absent from the "BIOS" setup, I got the idea that the technician doing a mainboard swap some weeks ago might have forgotten to reconnect the NFC module.
Turns out that was indeed the case 🤦. While the NFC reader is now detected, it still didn't read any tags 🧵 1/3
https://assets.chaos.social/media_attachments/files/116/024/455/075/402/017/original/bc436d718c1b3b56.jpg

2026-01-29 20:02:27 UTC

- reply

There you go.
https://assets.chaos.social/media_attachments/files/115/980/162/576/419/961/original/644a71ceae154b51.png

2026-01-29 18:37:31 UTC

One of them isn't like the other.
https://assets.chaos.social/media_attachments/files/115/979/835/878/439/057/original/e187fb6ba64c943a.jpg

2025-12-11 20:42:47 UTC

- reply

This! Or beat the technology connections guy with an even faster kettle.
People need to do more silly stuff now that half a megawatt of electrical power is easily accessible.

2025-07-18 18:05:54 UTC

- reply

Turns out, it's worse than this: The ipv6-literal.net shenanigans aren't limited to UNC paths.
It works in all places:
> ping 2a0e-3c0--21.ipv6-literal.net
Pinging 2a0e:3c0::21 with 32 bytes of data:
Also works in browsers: http://2a0e-3c0--21.ipv6-literal.net/
Thanks to @npub1a09…pult for asking.

2025-07-18 17:04:30 UTC

Mildly cursed factoid about UNC paths:
- UNC Paths can contain IP addresses such as \\192.168.1.1\share
- IPv6 addresses are supported as well
- IPv6 addresses contain colons
- can't have colons in Windows paths since colons are reserved for drive letters
So Microsoft came up with the the ipv6-literal.net domain that's special-cased by Windows so you can to write IPv6 addresses in UNC paths as 2a0e-3c0--21.ipv6-literal.net without it hitting any resolvers.

2025-01-11 18:52:59 UTC

Since everyone here seems to love cursed technology, I made a chart rating various interfaces by their perceived cursedness.
Some like 10G BASE-T have a reason for being cursed, whereas others like USB PD not so much.
Any additions?
https://assets.chaos.social/media_attachments/files/113/811/201/388/930/349/original/23fcba0bfa436778.png

2024-12-22 20:17:25 UTC

- reply

Epoxy a hook to the chip package:https://www.ipc.org/sites/default/files/test_methods_docs/2.4.53.pdf

2024-12-22 20:12:42 UTC

- reply

How much of a difference does it make whether you pry off the chip with a knife or rip it off perpendicular to the board with a proper fixture?

2024-11-24 21:55:10 UTC

The NFC reader on recent ThinkPads actually works more-or-less out-of-the box on Linux! Install and start https://github.com/linux-nfc/neard and detected tags pop up as D-Bus objects.
The scripts from the test directory interact with them for quick and easy testing.
Now to find something useful to do with it.

2024-11-11 21:14:44 UTC

Cursed BGA package (from https://youtu.be/rVJwcZavr9U?t=1311)
https://assets.chaos.social/media_attachments/files/113/466/185/732/344/014/original/839b74d0a653fbc5.png

2024-10-30 22:07:11 UTC

How many digits of pi do you know from the top of your head?

2024-09-26 14:40:43 UTC

Have been thinking of this for way too long, so here you go:
S-Parameters explained for public transport nerds
https://assets.chaos.social/media_attachments/files/113/200/355/752/435/763/original/37ff5ed0bab78ff9.png

2023-10-01 11:16:06 UTC

Smith charts always reminded me of the the window color mandalas we did back in kindergarten.
So I got a set of window color paint and did just that 🌈
https://assets.chaos.social/media_attachments/files/111/159/195/035/717/916/original/3f1883a835270639.jpeg