Comment 2 for bug 1908855

A bisect against the test suite shows this was caused by the recent update:

078708192bba5337afbec0952e104bd587824e65
Add support for user defined mount options

$ sudo git bisect log
git bisect start
# good: [7e2a4dbfac7c51415f6d3875a50e1c93bf3eae9d] Support metacopy with nested overlay configuration
git bisect good 7e2a4dbfac7c51415f6d3875a50e1c93bf3eae9d
# bad: [95be14ee4dd75c5a2b2ae4d05df6c8810ac09737] Allow user provided options with or without -o
git bisect bad 95be14ee4dd75c5a2b2ae4d05df6c8810ac09737
# bad: [078708192bba5337afbec0952e104bd587824e65] Add support for user defined mount options
git bisect bad 078708192bba5337afbec0952e104bd587824e65
# good: [019085f43d7e6426378ccfd3deeb23e127449e3e] Relax layers check for older kernels
git bisect good 019085f43d7e6426378ccfd3deeb23e127449e3e
# first bad commit: [078708192bba5337afbec0952e104bd587824e65] Add support for user defined mount options