A couple of things to note:

* Despite the earlier title; this does not just apply to VMs; any system with a potentially-blocking getrandom() (including all Linux 3.17+ and Solaris 11+) is affected.

* It's true that getrandom() only blocks on Linux when called before the RNG entropy pool is initialized. However, Python should not be limited to only being called after this initialization.

* In particular, systemd-cron relies on a Python script being called very early in the boot process (before the urandom pool is initialized), this is now prevalent on the Debian testing track; causing a 90-second boot delay.

* The patch I supplied causes getrandom() to be only called in nonblocking mode; this seems consistent with the desired semantics of os.urandom and _PyRandomInit.

Hope this helps.

Colm