Re: [Qemu-devel] [PULL 00/24] Linux-user updates

[Laurent Vivier]

> Le 18 août 2014 à 14:45, Peter Maydell <address@hidden> a écrit :
>
>
> On 18 August 2014 13:38, Joakim Tjernlund <address@hidden> wrote:
> > Peter Maydell <address@hidden> wrote on 2014/08/18 12:58:48:
> >> Well, binfmt-misc works fine for me as it is and presumably
> >> for most people or we'd have had more complaints. So
> >> breaking all those existing working setups is really something
> >> we should avoid as much as possible.
> >
> > How do you use it? With LXC booting a VM with traditional init?
>
> No. Just a straightforward chroot environment with a
> statically linked qemu in it, and a binfmt_misc config like:
>
> e104462:trusty:qemu$ cat /proc/sys/fs/binfmt_misc/qemu-arm
> enabled
> interpreter /usr/bin/qemu-arm-static
> flags: OC
> offset 0
> magic 7f454c4601010100000000000000000002002800
> mask ffffffffffffff00fffffffffffffffffeffffff
>
> This works fine for the things I try to run in the chroot
> (mostly test programs, also bash and basic command
> line utilities).
>
> > There are complaints which dists had to solve because QEMU didn't. Usually
> > this is a separate static QEMU package/hack with a binfmt wrapper.
> > Gentoo used to have one but this got removed.
>
> I'm sure there are cases which don't work; but we should try
> to find a way which allows us to make those work (with a
> recommended change to binfmt misc registration) which
> doesn't break the old configs in the process.

If it can help:

 

I'm using qemu-linux-user in LXC containers for more than a year now without any problem and with nor wrapper neither modifications in the distro I install (to be honest, only debian etch-m68k and previous).

I like this approach because it avoids to have to maintain gcc cross-compiler (and tools). It's 10 times slower than the cross compiler but works fine.

 

I've a script in my qemu-m68k repo that can create containers for several archs (search in QEMU mailing list archives... or ask)

 

Regards,

Laurent