Dan Connolly's tinkering lab notebook

Javascript on genode, genode on HP Envy 15

Genode is a microkernel operating system with capability-based security; in the 20.05 release they added capability-based security using seccomp on Linux. That got me excited enough to make some real progress on JavaScript on Genode using the Moddable XS engine and on Genode on an HP Envy laptop.

In genode-js-xs I got this JavaScript code running on genode:

export default function main() {
    let message = "Hello, world - sample";
    trace(message + "\n");

It works like this, once it's built (see below):

goa-hello$ goa run
[goa-hello:make] recursive make: make
Genode 20.02-1-gac1b2ec24e
17592186044415 MiB RAM and 8997 caps assigned to init
[init -> goa-hello] Hello before libc
[init -> goa-hello] hello via stdio
[init -> goa-hello] Hello in libc
[init -> goa-hello] lin_xs_cli: loading top-level main.js
[init -> goa-hello]  lin_xs_cli: loaded
[init -> goa-hello] lin_xs_cli: invoking main(argv)
[init -> goa-hello] Hello, world - sample
[init -> goa-hello] main() returned immediate value (not a promise). exiting
[init -> goa-hello] Warning: rtc not configured, returning 0
Warning: blocking canceled in entrypoint constructor
[init] child "goa-hello" exited with exit value 0

I started with the hello package from then Nov 2019 article introducing goa.

Then I grabbed the helloworld example from the Moddable XS SDK, generated C sources, and got it to build.

Then I worked out getting goa run to work. My artifacts is a bit of a kludge: it reaches out from var/build back to src/bin.

before goa build: gensrc, genode_platform

There's a bit of an impedence mismatch between goa build and the Moddable SDK, so use make -C src gensrc to generate C etc. before running goa build.

We also extend the Moddable SDK to add a genode platform using make -C src genode_platform.

Next Steps

  • event loop: Figure out how to integrate the port of glib to genode to turn the event loop, which is currently commented out, back on.

  • nix and dhall: Compare goa to genodepkgs

NixOS 20.03 and Genode Sculpt 20.02 on the HP Envy 15

When my son upgraded his gaming laptop last year, I got his hand-me-down HP ENVY 15z-j100 and tried to boot it from free software. I got Windows so messed up that it could neither boot nor repair itself, so I set it aside in frustration.

Prompted by my success with js on genode, I tried a Ubuntu 20.04 USB stick (that I had made for my other son, who uses linux for his gaming PC) and lo, it worked the first time. Ubuntu has gone to the trouble to get their installation media working with secure boot.

secure boot for NixOS looks really bleeding edge, but with a better understanding based on EFI Boot Loaders for Linux: Dealing with Secure Boot by Rod Smith, I managed to turn secure boot off and get NixOS installed.

With all this momentum, I did not give up when booting Sculpt OS 20.02 quit with a just screen full of (?)s. They only document support for Intel CPUs and this has an AMD A10-5750M, so it looked like an AHCI driver problem or some such. But the screen wasn't locked altogether. It responded to enter and to clear... aha! It's a grub prompt with a missing font. terminal_output console dealt with the font issue and the solution turned out to be changing hd0 to hd1 in a grub config file. Genode has no ath9k driver, so wifi isn't working, but I have plenty of ethernet ports and cables. :)