Re: [Qemu-devel] Target-agnostic virtio?

[Rob Landley]

On 04/20/2013 05:36:46 AM, Blue Swirl wrote:
> > I plan to add a sparc64 target built from source to Aboriginal  
> Linux.
> >
> > For a lot of the 64-bit targets, actual 64 bit userspace support is
> > strangely lacking. For ppc64 they say to use ppc32, and I've been  
> told that
> > about sparc64 as well. I don't know if this is an optimization or a
> > requirement. I have a 32 bit image, I'd like to test the 64 bit  
> codepaths as
> > well...
>
> It's a sort of optimization, the pointers are smaller. OpenBSD/sparc64
> takes a different approach, every binary is 64 bits. Would it be hard
> to make Aboriginal *BSD? ;-)

Not _that_ hard, but I'm not sure it's interesting?

Aboriginal Linux is basically 7 packages: linux, gcc, binutils, uClibc,  
make, bash, and busybox. (I also add distcc so the native toolchain can  
move some of the heavy lifting of compilation outside the emulator, but  
that's optional.)

This is the smallest system capable of not only rebuilding itself under  
itself, but building Linux From Scratch under the result (and thus  
natively bootstrapping up to an arbitrary set of packages).

I'm gradually replacing busybox with toybox, and I'm migrating from  
uClibc to musl. I vaguely plan to read the various klibc arch support  
bits to add new architectures to musl, but my day job doesn't have  
anything to do with my hobby programming so there's a chronic shortage  
of time, and toybox 1.0 is my priority right now for reasons I blatered  
at length about at ELC a month or so back (http://youtu.be/SGmtP5Lg_t0).

In theory swapping in a bsd kernel and libc, and beating the toolchain  
into accepting it, might not be too hard. But what I'm more likely to  
do is try to add sparc64 support to musl and convince the toolchain  
it's just going to have to cope with the idea of a 64 bit sparc  
userspace.

Rob