ZFS Comment tests:

Test 1:  rpool switch to-and-from, no comments

	- Boot with baseline.

	- Reboot with zfs-comment.

	- Check for default comment value.  (And that spa_comment == NULL.)

	- Reboot with baseline.

	- Verify baseline still boots.

Test 2: rpool switch to-and-from, add comments

	- Boot with zfs-comment.

	- Verify no-comment per test 1.

	- Add comment.

	- Verify comment.

	- Reboot with zfs-comment.

	- Verify comment.

	- Reboot with baseline.

	- Reboot with zfs-comment.

	- Verify no-comment per test 1.

Test 3: datapool implicit upgrade

	- Boot with baseline.

	- Create 'datapool' pool.

	- Reboot with zfs-comment.

	- Verify default comment value like rpool with test 1.

Test 4: datapool comment to-and-from (tests baseline handling of comment, too)

	- Boot with zfs-comment.

	- Verify no-comment per test 3.

	- Add comment.

	- Verify comment.

	- Reboot with zfs-comment.

	- Verify comment.

	- Reboot with baseline.

	- Import "datapool", then export it.

	- Reboot with zfs-comment.

	- Verify no-comment per test 3.

Test 5: export/import/export with comment

	- Boot baseline, export datapool.

	- Boot with zfs-comment.

	- Add comment to datapool.

	- Export datapool.

	- Utter "zpool import" to see comment is there.

	- Import datapool.

	- Verify comment.

	- Export datapool.

Test 6: See if comment is preserved if "baseline" doesn't import, but checks.

	- Reboot with baseline.

	- Utter "zpool import".

	- Reboot with zfs-comment

	- Verify comment on datapool.

Test 7: Using -o comment=new on import.

	- Boot with zfs-comment.

	- Export datapool.

	- Import datapool with -o comment="New comment".

	- Verify comment.

Test 8: Using -o comment=new on create.

	- Boot with zfs-comment.

	- Destroy datapool.

	- Create datapool, but with -o comment="Creation."

	- Verify comment.

Test 9: Test comment size limits

	- Boot with zfs-comment.

	- Make a comment larger than 32 characters.  Should fail.

Test 10: Test comment reality checking, libzfs

	- Boot with zfs-comment.

	- Make a comment with \<nl> in it using "zpool set".  Should fail.

Test 11: Test comment reality checking, import

	- Repeat test 10, but using -o comment="foo\<cr>bar".  Should work.

	- NOTE:  If this is a problem, we need isprint() for the kernel.

Test 12: Test comment reality checking, creation.

	- Repeat test 11, but with pool creation.

	- NOTE:  If this is a problem, we need isprint() for the kernel.