4 ms·

I'd love to have this in-depth level of knowledge of kernel inner workings. Super interesting writeup.

AshamedCaptain 2y ago
Binder is actually something that was designed for BeOS and PalmOS, so ironically it is not very tied to Linux and IMHO one of these technologies that Google uses to abstract themselves from Linux. (It still has something to do with the early implementations since I recognize some of the #define names..)
- pjmlp 2y ago
  It also provides a way for a pseudo-microkernel like architecture despite Linux, as many services run on their own process talking with the Linux kernel via Binder.
  - p_l 2y ago
    IIRC, Binder also still includes "passing" the scheduler quanta between procese6when making a call - meaning that when you make a call from process A to process B, instead of waiting for process B to be scheduled for execution, it is swapped in place of process A in scheduling - effectively, process A "pays" for the CPU tone that process B needs to service the call.
    - kaszanka 2y ago
      How do they ensure this under Linux?
      - fooblaster 2y ago
        They don't. There is some notion of priority boosting but with everything running as sched_other it does essentially nothing.
        p_l 2y ago
        After extra checking, yes, they hack around a lack of infrastructure on kernel through tricks with setting nice values - I do know of patches that implement more, but they ultimate never got upstreamed
- a-dub 2y ago
  that's right. i believe an internet famous 90s female beos engineer was behind it. diane hakbod?
  - saagarjha 2y ago
    Dianne (Hackborn, hackbod@) is still working on Android :)
    - sillywalk 2y ago
      From 2006(!) Interview and introduction to openbinder. https://www.osnews.com/story/13674/introduction-to-openbinder-and-interview-with-dianne-hackborn/ https://www.osnews.com/story/13674/introduction-to-openbinde...
- lmz 2y ago
  Or maybe they were referring to the exploitation parts needing to know about kernel allocator behavior etc.
giancarlostoro 2y ago
Which makes me wonder how does one read up on kernel internals outside of just perusing all the code, how do you get all the wonderful history that is just lost unless you talk to someone who worked on it or find an insightful comment on HN. The one thing version control should emphasize more of is a way to go back through commits and let people (probably approved people) comb through and comment the code in a metadata way that the version control software can display without affecting commits. Would be neat to peruse code, hover (if you have a good editor / IDE ;) and see commentary by others on said code.

Binder is actually something that was designed for BeOS and PalmOS, so ironically it is not very tied to Linux and IMHO one of these technologies that Google uses to abstract themselves from Linux. (It still has something to do with the early implementations since I recognize some of the #define names..)

pjmlp 2y ago
It also provides a way for a pseudo-microkernel like architecture despite Linux, as many services run on their own process talking with the Linux kernel via Binder.
- p_l 2y ago
  IIRC, Binder also still includes "passing" the scheduler quanta between procese6when making a call - meaning that when you make a call from process A to process B, instead of waiting for process B to be scheduled for execution, it is swapped in place of process A in scheduling - effectively, process A "pays" for the CPU tone that process B needs to service the call.
  - kaszanka 2y ago
    How do they ensure this under Linux?
    - fooblaster 2y ago
      They don't. There is some notion of priority boosting but with everything running as sched_other it does essentially nothing.
      - p_l 2y ago
        After extra checking, yes, they hack around a lack of infrastructure on kernel through tricks with setting nice values - I do know of patches that implement more, but they ultimate never got upstreamed
a-dub 2y ago
that's right. i believe an internet famous 90s female beos engineer was behind it. diane hakbod?
- saagarjha 2y ago
  Dianne (Hackborn, hackbod@) is still working on Android :)
  - sillywalk 2y ago
    From 2006(!) Interview and introduction to openbinder. https://www.osnews.com/story/13674/introduction-to-openbinder-and-interview-with-dianne-hackborn/ https://www.osnews.com/story/13674/introduction-to-openbinde...
lmz 2y ago
Or maybe they were referring to the exploitation parts needing to know about kernel allocator behavior etc.

giancarlostoro 2y ago

Which makes me wonder how does one read up on kernel internals outside of just perusing all the code, how do you get all the wonderful history that is just lost unless you talk to someone who worked on it or find an insightful comment on HN. The one thing version control should emphasize more of is a way to go back through commits and let people (probably approved people) comb through and comment the code in a metadata way that the version control software can display without affecting commits. Would be neat to peruse code, hover (if you have a good editor / IDE ;) and see commentary by others on said code.