[Qemu-devel] user emulation status?

[Tomasz Chmielewski]

According to the list of supported guest OSes on 
http://bellard.org/qemu/status.html, these architectures have "OK/green" 
status for user emulation:

x86, ARM, SPARC, PPC, MIPS, m68k, SH-4.

If these architectures are really fully supported by Qemu, it should be 
possible to run a chroot of another architecture (i.e. on x86 we chroot 
to ARM base filesystem/pcakages).

I thought I'd give it a try, with current Qemu SVN, by installing Debian 
for different architectures with debootstrap command (debootstrap allows 
to install base filesystem/packages).


Debian Etch supports ARM, SPARC, PPC and MIPS, so I only tested those on 
x86 PC.


Results:

1. ARM - support is really great.
debootstrap installs base filesystem/packages without any errors in an 
ARM chroot made on x86 PC.
It's even possible to start some GUI applications.


2. MIPS - support is not so great.
It's not possible to install a base filesystem.
Chrooting from x86 to an already existing MIPS filesystem works, but 
lots of commands just break (i.e., dpkg exits with "Invalid argument"; 
some stracing reveals more details).


3. PPC
Chrooting from x86 to a PPC filesystem ends with a segmentation fault.


4. SPARC
Chrooting from x86 to a SPARC filesystem works, but it's only possible 
to start one command. After that, qemu-sparc process dies with HELPME... 
(I used the default --sparc_cpu).


Are you people interested in running processes in a foreign chroot (i.e. 
ARM chroot on x86 PC)?


I wanted to set up some daily automated tests which would fetch current 
SVN, build for ARM, MIPS, PPC and SPARC targets, try to install Debian 
with debootstrap in a chroot.


So far I see though, that only ARM would get "OK" result, MIPS would get 
"partial"; PPC and SPARC would fail.

Does it make sense to trace it on a daily basis?



--
Tomasz Chmielewski
http://wpkg.org