Comment # 12 on bug 1207243 from Daniel Wagner

Sorry for the delay. My take on this is that the hang is not caused by nvme.
The message is a red herring. Your current up to date userspace is doing
reading 

  /sys/class/nvme/nvme0/nvme0n1/uuid

from the older kernel as well. The only difference is that the older kernel
doesn't show the warning as it is silenced. The newer kernel is using
a different 'printf' function which is now visible. On my system I see
it behave exactly the same.

That means we have to look at other things. Do you happen to gather
any other logs?