My fourth Obnam 3 development session. Put into place the scaffolding to add chunk encryption, but didn't have the time to actually implement the encryption.

Small steps and tea is the way to reach goals while having fun.

(Obnam 3 is my Sunday project to experiment with implementing fundamental components for backup software.)

https://obnam.org/blog/2025/obnam3-04

#obnam #backupImplementation

BREAKING: The C++ committee imposes tariffs on non-US locales.

Telegram asked me pin, which was 26214, which is same as the number of colors on #Amiga 1200 ;-)

That at least what I recall...

Quite cool, I have to say. fwupdmgr managed to update my HP USB-C Dock G5.

with refcount_inc_not_zero() trial in GC to fully sequence the time window of key_put(): https://lore.kernel.org/keyrings/20250403153809.213535-1-jarkko@kernel.org/

recycle is now free, the program to create .rex loops: https://www.reasonstudios.com/recycle

fun Linux fact: because MAP_SHARED|MAP_ANONYMOUS is actually a file-backed mapping under the hood, unmapping part of such a mapping does not discard the data stored in that part:

$ cat mremap.c
#define _GNU_SOURCE
#include <err.h>
#include <stdio.h>
#include <sys/mman.h>
int main(void) {
  char *p = mmap(NULL, 0x2000, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, -1, 0);
  if (p == MAP_FAILED) err(1, "mmap");
  p[0x1000] = 'X';
  if (munmap(p+0x1000, 0x1000)) err(1, "munmap");
  // that 'X' we just wrote... is it gone?
  // nope, let's bring it back!
  p = mremap(p, 0x1000, 0x2000, MREMAP_MAYMOVE);
  if (p == MAP_FAILED) err(1, "mremap");
  printf("p[0x1000]='%c'\n", p[0x1000]);
}
$ gcc -o mremap mremap.c
$ ./mremap
p[0x1000]='X'
$

It's actually somewhat similar concurrency dance as with SGX driver's page reclaimer... I think that refcount_inc_not_zero(&key->usage) should balance shit out but have to wait and see what David thinks...

@noodles Cloud access is destined to fail at some point when doing kernel testing or cap to some limitation, which you cannot simply achieve with that type of access. It does not really compare to a local machine...

@noodles This is true, not just a money question really :-) Would be nice to have something smaller scale and efficient.

refined: https://lore.kernel.org/keyrings/20250402085257.728844-1-jarkko@kernel.org/T/#u

@oleksandr i’d compare key idiomatically maybe more like task_struct because it is memory with type (like task is) 🙂 graveyard is just keys no longer used, ready for freed.

Or like, you have memory with identity (UID/PID vs serial). And in a memory reclaimer isolation is afaik more like when you pick passive victims. Here the list is a dead ramp, nothing comes back alive.

@oleksandr I just took the name from struct key for RFC. Did not give it much of thought to be honest... I.e., not something fighting for either :-)

https://lore.kernel.org/keyrings/20250329183243.719222-1-jarkko@kernel.org/T/#u

US government’s attack on free speech, science, and research is causing a brain drain

How do you create a brain drain and lose your status as eminent destination for scientists and researchers?

The United States seems to be sending out questionnaires to researchers at universities and research institutes outside of the United States, asking them about their political leanings. Dutch universities are strongly advising Dutch researches not to respond to the questionnaire

https://www.osnews.com/story/141972/us-governments-attack-on-free-speech-science-and-research-is-causing-a-brain-drain/

Antti Louhivaaran uusin kaiutin, Audio Anatomy AA5

8 Bits High live at a local museum near my home year ago:

https://www.youtube.com/watch?v=ioXT82QwgAo

Vapriikki (https://www.vapriikki.fi/en/) has e.g.,

1. Most extensive video game museum in Finland.
2. Some other tech stuff like the first ever IRC Server in a glass case ;-)

Great place to visit if around here.

#c64 #chiptune

This is insane:

https://www.nature.com/articles/d41586-025-00938-y

@kultpowerBot love the old school mags in any language :-)