Re: fakechroot + qemu user emulation

[Hector Oron <hector.oron@gmail.com>]

Hi,

2011/1/9 Johannes Schauer <j.schauer@email.de>:

> my goal is to build an armel rootfs without the need of super user
> privileges.
>
> using fakeroot, doing a debootstrap or multistrap is possible without
> the need of becoming root. using fakeroot i can even create device
> nodes and such without a problem but at some point i will have to
> chroot into the environment and execute some foreign binaries.
> (for example to execute dpkg --configure -a for a multistrap)
>
> for that i was using qemu-arm-static
> $ cp /usr/bin/qemu-arm-static $ROOTDIR/usr/bin
> and using the normal
> $ sudo chroot $ROOTDIR /bin/sh
> is working great but for that i have to have super user rights.
>
> so fakechroot comes to the rescue.
>
> in debootstrap with the same architecture as the host doing something
> like this will works:
> $ fakeroot fakechroot chroot $ROOTDIR_AMD64 /bin/sh
>
> but this does not work if $ROOTDIR contains an armel debootstrap/multistrap
> while i'm on amd64/i386.
> if i try i get (i already have qemu-arm-static copied over):
> $ fakeroot fakechroot chroot $ROOTDIR /bin/sh
> /lib/ld-linux.so.3: No such file or directory

Works for me (with warnings) with something like:

(it needs standard configuration for schroot.conf)

$ fakeroot debootstrap --foreign --arch=armel sid $ROOTDIR
$ cp /usr/bin/qemu-arm-static $ROOTDIR/usr/bin
$ sudo sh -c "echo 0 > /proc/sys/vm/mmap_min_addr"

$ fakeroot schroot -c sid_armel
ERROR: ld.so: object 'libfakeroot-sysv.so' from LD_PRELOAD cannot be
preloaded: ignored.
W: Failed to change to directory '/srv/chroot': No such file or directory
W: Failed to change to directory '/home/zumbi': No such file or directory
W: Falling back to directory '/'
I have no name!@cat:/$ uname -a
Linux cat 2.6.27.4 #1 SMP Wed Oct 29 16:47:28 UTC 2008 armv5tel GNU/Linux
I have no name!@cat:/$ exit
zumbi@cat:/srv/chroot$ uname -a
Linux cat 2.6.27.4 #1 SMP Wed Oct 29 16:47:28 UTC 2008 x86_64 GNU/Linux

Maybe, in the future, it can be integrated into schroot.

Best regards,
-- 
 Héctor Orón

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