Comment 9 for bug 1636467

Also I wanted to report that I can test and verify the issue on s390x:

$ lsscsi --wwn | grep sde
[1:0:0:1073889316]disk 0x6005076306ffd6b60000000000002 /dev/sde
$ ll /dev/disk/by-id/* | grep 'wwn.*sde'
/dev/disk/by-id/wwn-0x6005076306ffd6b60000000000002402 -> ../../sde

"402" is the lost info.

One more reason which makes this even less important IMHO is that usually those disks are driven with multipathing and as soon as that is set up the wwn is linked to the device mapper object.
=> /dev/disk/by-id/wwn-0x6005076306ffd6b60000000000002402 -> ../../dm-0

After that "lsscsi" is no more seeing anything in regard to the wwn:
lsscsi --wwn | grep sde
[1:0:0:1073889316]disk /dev/sde

An extra bug - I don't think so, just the fact that the WWN is not represented by a single disk anymore. Even before multipath only one of many "disks" to the same WWN owns the wwn.
[1:0:0:1073889316]disk 0x6005076306ffd6b60000000000002 /dev/sde
[1:0:0:1073954852]disk /dev/sdf
[1:0:1:1073889316]disk /dev/sdg
[1:0:1:1073954852]disk /dev/sdh

Anyway all that might be a reason not to SRU it, but clearly it should be fixed still.
Once that is resolved it might be a good trigger to pull a newer version into Debian and Ubuntu.
While development is super slow there are at least a few fixes.
We should help to push a newer one to Debian soon in the aa-cycle so we can sync it into aa.
At that time we can look at the progress of this fix.