Re: How to use the L4 Microkernel with a FreeBSD userland.

From: Mario Marietto <marietto2008_at_gmail.com>
Date: Sun, 11 Feb 2024 19:43:59 UTC
ok. But what does this mean ? That I can use whatever Linux distro I want ?
Or even the FreeBSD world ?

On Sun, Feb 11, 2024 at 7:59 PM Mark Millard <marklmi@yahoo.com> wrote:

>
>
> On Feb 11, 2024, at 05:44, Mario Marietto <marietto2008@gmail.com> wrote:
>
> > I'm trying to understand how to use the L4 Microkernel with a FreeBSD
> userland. I've asked the same to a L4 developer,but he told me that he does
> not know FreeBSD,so I'm here to ask the same question. First of all I'm
> sure that it can be done,because it is written clearly on their website :
> >
> >
> > http://os.inf.tu-dresden.de/L4Re/download/snapshots/
> >
> >
> > on the section :
> > Host system requirements
> > The host system shall be a 64bit-based system with a recent Linux
> distribution installed and at least 2GB of free disk space.
> > All necessary tools required by the build are available from the
> provided packages of the Linux distributions, including cross compilers.
> But there are also other cross compiler packages available (see below). You
> might want to run make check_build_tools in the src/l4 directory to verify
> the common tools are installed.
> > You are free to use any Linux distribution you like, or even BSDs or any
> of its derivatives. But then you should know the game. Especially tool
> versions should be recent, as installed on the listed distributions below.
> > We are confident that the snapshot works on the following distributions:
> >     • Debian 11 or later
> >     • Ubuntu 22.04 or later
> >
> > Let's say I want to use the L4 microkernel + FreeBSD 14 on my Raspberry
> Pi 4,the first step I did was to build L4Re for the Rpi,according with this
> instructions :
> >
> >
> > http://os.inf.tu-dresden.de/L4Re/rpi.html
> >
> > This is the log file of the compilation,that hasn't given any  error :
> >
> >
> > https://pastebin.ubuntu.com/p/6SwN2mpJBM/
> >
> >
> > Or I could have taken a pre built image of the L4 microkernel here :
> >
> >
> > http://os.inf.tu-dresden.de/download/snapshots/pre-built-images/arm64/
> >
> >
> >
> > At this point the tutorial says that I should use a Linux distro. They
> suggest the official distro for the Raspberry Pi 4,that's RaspBian. But I
> don't want to use Linux as a userland,I want to use FreeBSD. The question
> now is : what should I do to achieve that goal ? How can I link the L4
> microkernel with the ubldr bootloader of FreeBSD ? Or should I link it to
> the kernel of FreeBSD ? Can someone explain to me the missing step ? thanks.
>
> QUOTING the "Configuring yourself" section:
> The make setup step configures predefined setups for both the L4Re
> microkernel (Fiasco) and the L4Re user-level software, and connects both
> together so the images for the target system can be built.
> END QUOTE
>
> So L4Re has its own user-level software, not just a kernel. There is no
> use of a Linux or FreeBSD user-level software
> when L4Re is booted. (They are just used for building.)
>
> "The host system" is just a host for building the L4Re parts and
> assembling the image from the parts. The "Pulling it together" section is
> about combining the parts (including the microkernel and the user-level
> software) to make the overall image that does not include Linux or FreeBSD
> code.
>
>
> ===
> Mark Millard
> marklmi at yahoo.com
>
>

-- 
Mario.