== root uid=0 opening /mnt/hammer/testfile
HAMMERIOC_ADD_VOLUME (non-NUL device_name): rc=-1 errno=63 (File name too long)
As expected: install failed -- kstrdup-captured leaked name is not a valid path; vol_name freed.
LIST_VOLUMES after failed ADD: rc=0 errno=0 nvols=1
  [0] vol_no=0 device_name='/dev/vn0' len=8
RUN_EXIT=0