have you considered forking existing OS and implementing changes that you needed instead?
it's hard for me to justify the tremendous effort of implementing the OS from scratch, instead of adding the functionality that you need to for example linux or xv6.
> (it) exposes primitives that let a single experiment switch privilege levels at runtime while executing the same instructions in the same address space.
i think that it can be achieved by following linux modifications:
- make all executable pages executable both in user and kernel mode
- define a new syscall number, let's call it 'fractal'
- upon 'svc' trap (syscall), if it's a fractal syscall, just branch to instruction after the 'svc' (still in kernel mode! no 'eret', as opposed to no-fractal syscalls)
their costs are bound to compute anyway, they don't mind huge compensations also - it's not much of a cost saving to re-build, even cheaply, inhouse Slack or whatever?
it's hard for me to justify the tremendous effort of implementing the OS from scratch, instead of adding the functionality that you need to for example linux or xv6.
> (it) exposes primitives that let a single experiment switch privilege levels at runtime while executing the same instructions in the same address space.
i think that it can be achieved by following linux modifications:
- make all executable pages executable both in user and kernel mode
- define a new syscall number, let's call it 'fractal'
- upon 'svc' trap (syscall), if it's a fractal syscall, just branch to instruction after the 'svc' (still in kernel mode! no 'eret', as opposed to no-fractal syscalls)
and.. that's it?