On Tue, 30 Jul 2019 at 10:29, Jan Kara <jack@xxxxxxx> wrote:
>
> Thanks for the notice and the references. What's your version of
> util-linux? What your test script does is indeed racy. You have there:
>
> echo Running:
> for i in {a..z}{a..z}; do
> mount $i.squash /mnt/$i &
> done
>
> So all mount(8) commands will run in parallel and race to setup loop
> devices with LOOP_SET_FD and mount them. However util-linux (at least in
> the current version) seems to handle EBUSY from LOOP_SET_FD just fine and
> retries with the new loop device. So at this point I don't see why the patch
> makes difference... I guess I'll need to reproduce and see what's going on
> in detail.
We've observed this in arch with util-linux 2.34, and ubuntu 19.10
(eoan ermine) with util-linux 2.33.
just to be clear, the initial reports didn't involve a zany loop of
mounts, but were triggered by effectively the same thing as systemd
booted a system with a lot of snaps. The reroducer tries to makes
things simpler to reproduce :-). FWIW, systemd versions were 244 and
242 for those systems, respectively.
