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Quite disappointing someone would enable that kernel option without fully considering the ramifications :/. Do some distributions use systemd-coredump by defau

by _flux 4y ago

Quite disappointing someone would enable that kernel option without fully considering the ramifications :/. Do some distributions use systemd-coredump by default? I not just learned about systemd-coredump and I'm wondering if it could be actually useful for develoment purposes; apport doesn't seem to be.

rwmj 4y ago
I use systemd-coredump all the time on Fedora, it's pretty convenient. When a program crashes, run "coredumpctl gdb" to launch gdb on the latest coredump.
rollcat 4y ago
systemd-coredump is vuln, systemd-oomd kills the wrong stuff, and you don't even learn that these programs exist (and are running on your system) until you find out from a CVE or a blog post detailing how to mitigate the problem[1]. [1]: https://utcc.utoronto.ca/~cks/space/blog/linux/SystemdOomdNowDisabled https://utcc.utoronto.ca/~cks/space/blog/linux/SystemdOomdNo... And then, there are very few alternatives, because more and more software requires systemd (and even if most things still don't, so much stuff requires glibc so Alpine or OpenBSD aren't always very good as alternatives).
- jwilk 4y ago
  The systemd-oomd post discussed on HN: https://news.ycombinator.com/item?id=33894469 https://news.ycombinator.com/item?id=33894469 (2 weeks ago, 134 comments)
- blueflow 4y ago
  You can turn the situation around: Pick some non-systemd OS, stick to it, and avoid software that does not run on it. You will end up with the old and boring tech, but it will be robust and run more reliable in the long term. I've been running Alpine Linux in production for 4 years now.
  - CameronNemo 4y ago
    You will end up with the old and boring tech Not always. I have sway and pipewire running smooth as can be on my systemd-free workstation. As well as recent releases of Linux, glibc, Mesa, and Firefox. All the essentials are there and up to date for me!
    - adrian_b 4y ago
      That's true. I am using Gentoo with no systemd and with the latest versions of all programs that I am interested in.
  - rollcat 4y ago
    Unfortunately systemd & glibc (or even macOS) are usually the more pragmatic choice. I'd love to have the freedom to ignore them, but even outside of work, there is software (like games) that I want to run that doesn't play nice with anything more sane.
    - blueflow 4y ago
      The glibc 2.26 breakages (including the ucontext thing) were what made me stick to musl/Alpine. This was in 2017, around the same time poettering did the "i don't consider this much of a problem"-things on github.
  - 4khilles 4y ago
    Alpine's great. My entire homelab runs on it. Only complaint I have is its IPv6 support sucks. I have to hack together a bunch of scripts to get a reasonable network configuration.
    - blueflow 4y ago
      I had no trouble with IPv6. For static config i add it to /etc/network/interfaces, for dynamic config i use dhcpcd without issues.
  - zajio1am 4y ago
kirbyfan64sos 4y ago
systemd-coredump is honestly incredibly useful. Any time an application randomly crashes in the background, you can easily pop it in a debugger to look through the backtrace without having to re-run it. Very handy for when the crashes are not easily reproducible, or you didn't expect something to fail and are not sure how to make it fail again.
- ghostpepper 4y ago
  As far as I can tell all the magic you're describing is provided by the kernel's core dumper and not systemd. You can achieve the same effect by creating /tmp/cores and setting a meaningful pattern in /proc/sys/kerne/core_pattern.
- hansel_der 4y ago
  coredumping crashed applications (or the kernel) was not invented by systemd
- eqvinox 4y ago
  It's also incredibly annoying, because it changes longstanding cross-platform common behavior regarding this exact functionality. "A coredump is written to the crashing process's current working directory, named 'core' or 'core.<pid>'" - that used to be true on Linux and all the BSDs. Several setups of ours rely on that fact, and since we're developing software that is supposed to work on Linux and {Free,Open,Net}BSD, we were happy to be able to reuse a bunch of crash-capture logic. systemd kneecapped us out of the blue, it took us some time to figure out where the coredumps were going. Now we disable systemd-coredump on all systems. Which works, except when something reenables it or we add a new platform and someone forgets to disable it. Sigh. Yes, we can deal with it, by disabling it. But crash captures went from being reliable to "did systemd-coredump creep back in?" - a definite regression.
  - ciupicri 4y ago
    > except when something reenables it Have you tried masking it? (https://www.freedesktop.org/software/systemd/man/systemctl.html#mask%20UNIT%E2%80%A6 https://www.freedesktop.org/software/systemd/man/systemctl.h...)
bdhcuidbebe 4y ago
systemd-coredump is on my arch and i dont remember setting it up, anyway its rather cool, it even collects core dumps from podman
mhitza 4y ago
Fedora has it bundled by default. I've used it once, recently, to report a pipewire crash with bluetooth headphones.

by _flux 4y ago

rwmj 4y ago

I use systemd-coredump all the time on Fedora, it's pretty convenient. When a program crashes, run "coredumpctl gdb" to launch gdb on the latest coredump.

rollcat 4y ago

systemd-coredump is vuln, systemd-oomd kills the wrong stuff, and you don't even learn that these programs exist (and are running on your system) until you find out from a CVE or a blog post detailing how to mitigate the problem[1]. [1]: https://utcc.utoronto.ca/~cks/space/blog/linux/SystemdOomdNowDisabled https://utcc.utoronto.ca/~cks/space/blog/linux/SystemdOomdNo... And then, there are very few alternatives, because more and more software requires systemd (and even if most things still don't, so much stuff requires glibc so Alpine or OpenBSD aren't always very good as alternatives).

jwilk 4y ago
The systemd-oomd post discussed on HN: https://news.ycombinator.com/item?id=33894469 https://news.ycombinator.com/item?id=33894469 (2 weeks ago, 134 comments)
blueflow 4y ago
You can turn the situation around: Pick some non-systemd OS, stick to it, and avoid software that does not run on it. You will end up with the old and boring tech, but it will be robust and run more reliable in the long term. I've been running Alpine Linux in production for 4 years now.
- CameronNemo 4y ago
  You will end up with the old and boring tech Not always. I have sway and pipewire running smooth as can be on my systemd-free workstation. As well as recent releases of Linux, glibc, Mesa, and Firefox. All the essentials are there and up to date for me!
  - adrian_b 4y ago
    That's true. I am using Gentoo with no systemd and with the latest versions of all programs that I am interested in.
- rollcat 4y ago
  Unfortunately systemd & glibc (or even macOS) are usually the more pragmatic choice. I'd love to have the freedom to ignore them, but even outside of work, there is software (like games) that I want to run that doesn't play nice with anything more sane.
  - blueflow 4y ago
    The glibc 2.26 breakages (including the ucontext thing) were what made me stick to musl/Alpine. This was in 2017, around the same time poettering did the "i don't consider this much of a problem"-things on github.
- 4khilles 4y ago
  Alpine's great. My entire homelab runs on it. Only complaint I have is its IPv6 support sucks. I have to hack together a bunch of scripts to get a reasonable network configuration.
  - blueflow 4y ago
    I had no trouble with IPv6. For static config i add it to /etc/network/interfaces, for dynamic config i use dhcpcd without issues.
- zajio1am 4y ago

kirbyfan64sos 4y ago

systemd-coredump is honestly incredibly useful. Any time an application randomly crashes in the background, you can easily pop it in a debugger to look through the backtrace without having to re-run it. Very handy for when the crashes are not easily reproducible, or you didn't expect something to fail and are not sure how to make it fail again.

ghostpepper 4y ago
As far as I can tell all the magic you're describing is provided by the kernel's core dumper and not systemd. You can achieve the same effect by creating /tmp/cores and setting a meaningful pattern in /proc/sys/kerne/core_pattern.
hansel_der 4y ago
coredumping crashed applications (or the kernel) was not invented by systemd
eqvinox 4y ago
It's also incredibly annoying, because it changes longstanding cross-platform common behavior regarding this exact functionality. "A coredump is written to the crashing process's current working directory, named 'core' or 'core.<pid>'" - that used to be true on Linux and all the BSDs. Several setups of ours rely on that fact, and since we're developing software that is supposed to work on Linux and {Free,Open,Net}BSD, we were happy to be able to reuse a bunch of crash-capture logic. systemd kneecapped us out of the blue, it took us some time to figure out where the coredumps were going. Now we disable systemd-coredump on all systems. Which works, except when something reenables it or we add a new platform and someone forgets to disable it. Sigh. Yes, we can deal with it, by disabling it. But crash captures went from being reliable to "did systemd-coredump creep back in?" - a definite regression.
- ciupicri 4y ago
  > except when something reenables it Have you tried masking it? (https://www.freedesktop.org/software/systemd/man/systemctl.html#mask%20UNIT%E2%80%A6 https://www.freedesktop.org/software/systemd/man/systemctl.h...)

bdhcuidbebe 4y ago

systemd-coredump is on my arch and i dont remember setting it up, anyway its rather cool, it even collects core dumps from podman

mhitza 4y ago

Fedora has it bundled by default. I've used it once, recently, to report a pipewire crash with bluetooth headphones.