qemu-s390x-static: segmentation fault entering chroot

[Ken Sharp]

Host: Ubuntu Trusty i386
Guest: Debian Sid s390x

When attempting to debootstrap a Debian Sid s390x guest the second stage process immediately fails with a segmentation fault, and any subsequent attempts to run any command while in the chroot.

I: Running command: chroot s390x /debootstrap/debootstrap --second-stage
Segmentation fault (core dumped)
# chroot s390x/
# ps
Segmentation fault (core dumped)
# ls
Segmentation fault (core dumped)
# exit
exit

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: qemu-user-static 1.6.0+dfsg-2ubuntu4
ProcVersionSignature: Ubuntu 3.12.0-4.12-generic 3.12.1
Uname: Linux 3.12.0-4-generic i686
ApportVersion: 2.12.7-0ubuntu1
Architecture: i386
Date: Sat Nov 30 18:19:59 2013
InstallationDate: Installed on 2013-11-29 (1 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha i386 (20131126)
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: qemu
UpgradeStatus: No upgrade log present (probably fresh install)

[Serge Hallyn (serge-hallyn)]

Thanks for reporting this bug - could you please re-test with the 1.7
version now in trusty and let us know if that fixes it?

Could you please give the precise full command you used?

[Ken Sharp (kennybobs)]

Version: 1.7.0+dfsg-2ubuntu3

No change.

[Serge Hallyn (serge-hallyn)]

reproduced with:

sudo qemu-debootstrap --verbose --components=main,universe --arch=s390x stable x

[Serge Hallyn (serge-hallyn)]

Also reproduced with today's git HEAD, after doing

git clone git://git.qemu.org/qemu.git
cd qemu
./configure --target-list=s390x-linux-user --static --disable-system
make clean && make -j4
sudo cp s390x-linux-user/qemu-s390x /usr/bin/qemu-s390x-static
sudo qemu-debootstrap --verbose --components=main,universe --arch=s390x stable y

[Ken Sharp (kennybobs)]

Version: 1.5.0+dfsg-3ubuntu5.2

This doesn't occur in version 1.5.0 in Saucy. Regression?

The second stage fails anyway because it claims it cannot find /debootstrap/debootstrap which is similar to other open bugs, but there is no segfault.

[Peter Maydell (pmaydell)]

Does this patch fix this issue? http://patchwork.ozlabs.org/patch/309529/

[Ken Sharp (kennybobs)]

It certainly does!

[Serge Hallyn (serge-hallyn)]

This fix is upstream, so it will be pulled in when we switch to qemu 2.0 in 14.04.