L4/Alpha palcodes

Goswin Brederlow goswin.brederlow at student.uni-tuebingen.de
Fri Jan 25 03:22:45 CET 2002


"Udo A. Steinberg" <reality at delusion.de> writes:

> Adam 'WeirdArms' Wiggins wrote:
> > 
> >         Dresden proposed a user mode L4 project. Ie running L4/(arch blah)
> > on top of Linux/(arch blah).
> 
> I'm currently working on something like that. Give me a few months ;)

s/month/days/ :)

Any cvs?

> > > > The idea I have in mind is to make a module for linux that catches the
> > > > L4 syscalls and throws them back into user-space. That way a L4
> > > > environment could be setup within linux.  It would be much like
> > > > user-space-linux and would save a lot of reboots just to test out a
> > > > few bytes of code.
> 
> The native Linux kernel already partly does this for you. L4 syscalls are
> reflected to user mode as SIGSEGV in the offending program. With proper
> handling of those signals it ought to work.

Hmm, at least something that gets reported as segfaults, segfault
don't (according to the siginfo structure, which isn't filled out on
alpha).

> > > heh :) That would be an interesting project. I'd be interested to know
> > > how (if) you will deal with device drivers, memory etc.
> 
> User mode linux accesses memory through mmap'd pages. It also provides
> a few basic device drivers, i.e. the ubd filesystem which can possibly be
> made to work under L4 with some tweaking.

Does user mode linux work under alpha?

MfG
        Goswin




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