zfsonlinux/zfs — pull request #1785 by dweeezil (2013-10-12 22:48:44+00:00)
Title: Lock the DSL pool configuration in zpl_snapdir_iterate().

The new semantics introduced by the restructured sync task of illumos
3464 require this lock when calling dmu_snapshot_list_next().

Porting note:
I missed this when doing the original port because ZoL's control
directory code is Linux-specific and is in a different file than
in illumos.