Comment 2 for bug 1529449

Instead of requiring a serial of arbitrary length/format, I think a WWN/EUI-64 is more useful/important, not to mention that the WWN/EUI-64 can pretty much always be used as the serial at the same time.

Unlike Linux, Windows consider the WWN/EUI-64 as the "serial":

"C:\Windows\system32>sg_vpd -i PD1
Device Identification VPD page:
  Addressed logical unit:
    designator type: SCSI name string, code set: UTF-8
      SCSI name string:
      8086QEMU NVMe Ctrl 00012BDAC262CF831698

C:\Windows\system32>sg_vpd -p sn PD1
Unit serial number VPD page:
  Unit serial number: 0000_0000_0000_0000."

(https://bugs.launchpad.net/qemu/+bug/1576347/+attachment/4650553/+files/02.PNG)

UEFI also makes use of the WWN/EUI-64 to generate boot entries for NVMe devices:
https://bugs.launchpad.net/qemu/+bug/1576347/+attachment/4650554/+files/03.png
https://bugs.launchpad.net/qemu/+bug/1576347/+attachment/4650555/+files/04.png