sbuild chroot cleanup failed

[Tong Sun <suntong001@users.sourceforge.net>]

Hi,

I'm following
https://wiki.debian.org/sbuild#Apt_package_caching
to setup new schroot with eatmydata & ccache, but got "chroot cleanup
failed" afterwards.

Here is what I did:

sudo rm -r /srv/chroot/unstable-amd64-sbuild/
sudo rm /etc/schroot/chroot.d/unstable-amd64-sbuild-*
/etc/sbuild/chroot/unstable-amd64-sbuild

sudo sbuild-createchroot --include=eatmydata,ccache,gnupg unstable
/srv/chroot/unstable-amd64-sbuild
http://127.0.0.1:3142/deb.debian.org/debian

AOK so far, but when I tried to do
sudo sbuild-shell source:unstable-$arch-sbuild

then quit without doing anything, I'll get:

E: 10mount: E: Failed to open mount file â/proc/mountsâ: No such file
or directory
E: unstable-amd64-sbuild-d8cd8187-9a0a-47b0-ba1b-e0f0f5668e75: Chroot
setup failed: stage=setup-stop
Chroot cleanup failed


Tried twice (from a clean Debian sid environment), and twice got the
exact same error.

What is the problem and what should I do?

Thx!