Downgrading libgnutls30 from 3.5.3 (current yakkety) to the previous upstream version 3.5.2 (https://launchpad.net/ubuntu/+source/gnutls28/3.5.2-2ubuntu4/) fixes this. So apparently libgnutls now does a blocking getrandom() on startup, which is rather unfriendly as you cannot use the library during early boot any more.
Downgrading libgnutls30 from 3.5.3 (current yakkety) to the previous upstream version 3.5.2 (https:/ /launchpad. net/ubuntu/ +source/ gnutls28/ 3.5.2-2ubuntu4/) fixes this. So apparently libgnutls now does a blocking getrandom() on startup, which is rather unfriendly as you cannot use the library during early boot any more.