[lxc-users] 'Failed to whiteout' error in Trusty with 3.19 kernel

[Serge Hallyn]

Quoting overlay fs (overlayfs at gmail.com):
> > On Fri Aug 14 Thomas Müller wrote:
> > Hi everyone,
> >
> > I'm running Ubuntu trusty and recently upgraded to the new kernel (3.19).
> > When creating a snapshotted clone of a regular LXC container using
> > overlayfs, I'm now seeing the kernel error 'failed to whiteout'.
> >
> > Has anyone experienced a similar problem, is this a known issue already?
> >
> > Below some debug information:
> >
> > - Kernel error: http://pastebin.com/iajXHbHZ
> > - Kernel version: 3.19.0-25-generic #26~14.04.1-Ubuntu SMP Fri Jul 24
> > 21:16:20 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
> > - Executed LXC command: lxc-clone -s -B overlayfs orig test (both
> > unprivileged containers)
> > - LXC version: 1.0.7
> >
> > Any help/pointers would be appreciated.
> >
> > Best
> > Thomas
> 
> I can reproduce the 'failed to whiteout' error message, though not the
> kernel oops, in kvm.

Hi,

this isn't an lxc error, but a kernel bug.  You can't reproduce it with
a privileged container, right?  So I think it's a bug in the patches
supporting unprivileged use of overlayfs in the trusty sources for
linux-lts-vivid.  Can you open a bug or bring this up in #ubuntu-kernel?
(The error message shows up in ovl_do_whiteout_v1()).

-serge