4 ms·

Every boring problem found in eBPF (2022)

163 points by udev4096 2y ago

deleted 2y ago
[deleted]
magicalhippo 2y ago
BPF recently got published as an RFC[1], posted here[2] today and earlier here[3][4]. [1]: https://datatracker.ietf.org/doc/html/rfc9669 https://datatracker.ietf.org/doc/html/rfc9669 [2]: https://news.ycombinator.com/item?id=42051950 https://news.ycombinator.com/item?id=42051950 [3]: https://news.ycombinator.com/item?id=42024377 https://news.ycombinator.com/item?id=42024377 [4]: https://news.ycombinator.com/item?id=42038371 https://news.ycombinator.com/item?id=42038371
- tptacek 2y ago
  This is so weird to me. It's not an interoperable standard. It isn't even interoperable on Linux, the one OS where it's popular.
  - deleted 2y ago
    [deleted]
  - kimixa 2y ago
    If you wanted it to become an interoperable standard, that's the obvious step, right?
  - maxmcd 2y ago
    There is an explanation here: https://lwn.net/ml/all/20241105035101.GD41004@maniforge/ https://lwn.net/ml/all/20241105035101.GD41004@maniforge/
    - tptacek 2y ago
      Right, for offload, but XDP programs also depend on helper definitions, which themselves have not been consistent between versions of the Linux kernel.
      - stefan_ 2y ago
        And some (most?) of the helpers end up being "read memory at X", which has some obvious problems with offloading.
        tptacek 2y ago
        I mean, there really is working XDP offload (Netronome, right?) so it can be made to work, but this spec doesn't define the hardest part of interoperability.
        _flux 2y ago
        It probably still helps to have a standardised baseline. Then the vendors can just document deviations from it, and the deviations are probably quite small, not necessating new compilers for example (just guessing here ;)).
Retr0id 2y ago
By the way, this article is published as part of the tmp.0ut zine, and the CFP for the next issue is currently open: https://tmpout.sh/blog/vol4-cfp.html https://tmpout.sh/blog/vol4-cfp.html
warambo1010 2y ago
[dead]
humanfromearth9 2y ago
Wow that's a tl;dr for me. Not only because of the length, also because of format. Not very readable on a smartphone...
remram 2y ago
I'm usually against separate "mobile versions" of websites but wow, this needs one.

163 points by udev4096 2y ago

deleted 2y ago

[deleted]

BPF recently got published as an RFC[1], posted here[2] today and earlier here[3][4]. [1]: https://datatracker.ietf.org/doc/html/rfc9669 https://datatracker.ietf.org/doc/html/rfc9669 [2]: https://news.ycombinator.com/item?id=42051950 https://news.ycombinator.com/item?id=42051950 [3]: https://news.ycombinator.com/item?id=42024377 https://news.ycombinator.com/item?id=42024377 [4]: https://news.ycombinator.com/item?id=42038371 https://news.ycombinator.com/item?id=42038371

tptacek 2y ago
This is so weird to me. It's not an interoperable standard. It isn't even interoperable on Linux, the one OS where it's popular.
- deleted 2y ago
  [deleted]
- kimixa 2y ago
  If you wanted it to become an interoperable standard, that's the obvious step, right?
- maxmcd 2y ago
  There is an explanation here: https://lwn.net/ml/all/20241105035101.GD41004@maniforge/ https://lwn.net/ml/all/20241105035101.GD41004@maniforge/
  - tptacek 2y ago
    Right, for offload, but XDP programs also depend on helper definitions, which themselves have not been consistent between versions of the Linux kernel.
    - stefan_ 2y ago
      And some (most?) of the helpers end up being "read memory at X", which has some obvious problems with offloading.
      - tptacek 2y ago
        I mean, there really is working XDP offload (Netronome, right?) so it can be made to work, but this spec doesn't define the hardest part of interoperability.
        _flux 2y ago
        It probably still helps to have a standardised baseline. Then the vendors can just document deviations from it, and the deviations are probably quite small, not necessating new compilers for example (just guessing here ;)).

Retr0id 2y ago

By the way, this article is published as part of the tmp.0ut zine, and the CFP for the next issue is currently open: https://tmpout.sh/blog/vol4-cfp.html https://tmpout.sh/blog/vol4-cfp.html

warambo1010 2y ago

[dead]

humanfromearth9 2y ago

Wow that's a tl;dr for me. Not only because of the length, also because of format. Not very readable on a smartphone...

remram 2y ago

I'm usually against separate "mobile versions" of websites but wow, this needs one.