The code never returned match comparing two datasets (not snapshots).
As result, uu_avl_find(), called from zfs_callback(), never succeeded,
allowing to add same dataset into the list multiple times, for example:
# zfs get name pers pers pers@z pers@z
NAME PROPERTY VALUE SOURCE
pers name pers -
pers name pers -
pers@z name pers@z -
With the patch:
# zfs get name pers pers pers@z pers@z
NAME PROPERTY VALUE SOURCE
pers name pers -
pers@z name pers@z -
MFC after: 1 week
Sponsored by: iXsystems, Inc.
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