zfs test vdev_zaps_007_pos can fail
The zfs test vdev_zaps_007_pos can fail with:
13:39:10.02 SUCCESS: zpool create -f testpool mirror c3t0d0 c4t0d0 13:39:10.03 ASSERTION: Per-vdev ZAPs persist correctly on the original pool after split. 13:39:17.07 SUCCESS: zpool split testpool testpool2 c4t0d0 13:39:17.39
The blank line in the output is unfortunately is probably meant to be the actual error encountered that fails the test, but is not being saved for some reason.