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Comment by tripdout | Hacker News Reader

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

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..)

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.

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.

How do they ensure this under Linux?

They don't. There is some notion of priority boosting but with everything running as sched_other it does essentially nothing.

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

Or maybe they were referring to the exploitation parts needing to know about kernel allocator behavior etc.

that's right. i believe an internet famous 90s female beos engineer was behind it. diane hakbod?

Dianne (Hackborn, hackbod@) is still working on Android :)

From 2006(!) Interview and introduction to openbinder.

https://www.osnews.com/story/13674/introduction-to-openbinde...

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.

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