[buildd-tools-devel] Bug#626826: Bug#626826: Bug#626826: sbuild: /var/lock being absolute symlink -> "Another sbuild process (...) is currently using the build chroot"

[Roger Leigh]

On Sun, May 15, 2011 at 06:46:59PM +0100, Roger Leigh wrote:
> On Sun, May 15, 2011 at 07:25:19PM +0200, Jakub Wilk wrote:
> > Due to the advent of /run, I manually changed layout of my chroots,
> > so that they look like this:
> > 
> > $ ls -ld /srv/chroots/unstable-i386/{var,run}/lock
> > drwxrwxrwt 2 root root 4096 May 15 01:19 /srv/chroots/unstable-i386/run/lock
> > lrwxrwxrwx 1 root root    9 May 15 14:59 /srv/chroots/unstable-i386/var/lock -> /run/lock
> > 
> > Unfortunately, sbuild is not happy with such a layout, and I cannot
> > build more than one package in parallel (even though I use cloned
> > chroots, so it should be possible). I get this message instead:
> > 
> > Another sbuild process (job zlib_1.2.3.4.dfsg-3, pid 5534 by user sbuild) is currently using the build chroot; waiting...
> > 
> > It looks like sbuild uses /run/lock from the outside of the chroot.
> > When I changed the symlink to a relative one, the problem
> > disappeared.
> 
> Thanks for bringing this up.  I think that, by default, initscripts
> will leave the chroot /var/run and /var/lock in place, which implies
> that they will be separate from the host unless you switch to using
> /run with /var/run and /var/lock as symlinks (as you have done).
> However, this won't be the case for newly-debootstrapped chroots once
> base-files is updated.
> 
> I would certainly prefer to use relative symlinks--I took this up on
> debian-policy last week.  This is because relative symlinks between
> top-level directories must be absolute according to section 10.5.
> I'll certainly bring this issue to their attention.
> 
> sbuild could switch to using /run/lock directly.  However... if it's
> set up using the default scheme, it will be symlinked to /var/lock
> which will again be the host's /var/lock.

Alternatively, we can switch to using /var/lib/sbuild/chroot-lock
(for example).  This has the advantage of not using /var/lock.
However, while it would fix the immediate issue, it doesn't solve
the general problem of absolute symlinks and chroots.


Regards,
Roger

-- 
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