[systemd-devel] [PATCH] nspawn: allow 32-bit chroots from 64-bit hosts

[H. Peter Anvin]

On 02/18/2014 11:52 AM, Dave Reisner wrote:
> On Tue, Feb 18, 2014 at 02:44:14PM -0500, Dave Reisner wrote:
>> Arch Linux uses nspawn as a container for building packages and needs
>> to be able to start a 32bit chroot from a 64bit host. 24fb11120756
>> disrupted this feature when seccomp handling was added.
>> ---
>> Lennart suggested this approach, and it works nicely.
> 
> I suppose it's also possible to run an x32 chroot from an x86_64 host,
> so we might want to allow that. Alternatively, it seems we can just
> change the default action to allow (instead of kill) when a bad
> architecture is encountered. I don't know if there's side effects with
> that change that we'd want to avoid.
> 

And if you're on a 64-bit kernel with a 32-bit userspace (either i386 or
x32), you can launch a 64-bit chroot if you want to.  As such #ifdef
__x86_64__ seems wrong.

	-hpa