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Radiant Computer
@radiant.computer

Work has started on the Radiant Kernel. * It’s an exokernel. Very minimal. * It uses ring buffers as the only syscall interface (think io_uring). * There is no virtual memory — protection works via static analysis. * There are no device drivers, software has direct hardware access.

2 reposts18 likes

Radiant Computer
@radiant.computer

The kernel loader only accepts typed binaries (Radiance IL) that it can statically verify. Pointer fabrication or laundering can therefore be rejected at load time. The trade-off is that raw RV64 binaries are not accepted by the kernel.

Radiant Computer
@radiant.computer

This in turn means that virtual memory and paging are not necessary. For protection from untrusted binaries, it’s possible to use PMP (Physical Memory Protection) still, but this won’t be the default.

bryan english
@bengl.dev

This is certainly an interesting approach, though, with (I assume) an IL interpreter in the kernel and no virtual memory... what's left that needs a user mode? (Or are you just not using user mode?)

Superimposition
@superimposition.bsky.social

This feels very similar to an [bad?] idea I had after reading the singularity paper in my masters! My thought was that processes (almost) never trap into the kernel and instead communicate by some asynchronous message channel. Thanks for your work! It's inspiring to see

Radiant Computer
@radiant.computer

Yes, it’s possible to reduce traps as well as scheduler time to a bare minimum with clever kernel ABI design. All this research exists and sadly has not been put to use. You’re welcome!