Martin Matuska ceac02f8e6 Import fix for Illumos bug #1475 to reduce diff against upstream.
Panic caused by this bug was already partially fixed by pjd@
in p4 CH 185940 and 185942.

Reference:
1475 zfs spill block hold can access invalid spill blkptr
https://www.illumos.org/issues/1475

Reviewed by:	delphij
Obtained from:	Illumos (issue 1475, changeset 13469:b8e89e5c4167)
MFC after:	1 week
2011-10-18 13:58:22 +00:00
..