OpenJDK Client VM warning: INFO: os::commit_memory

[tschaffter]

If SELinux is enabled and its mode is set to enforcing, the controller should
have failed to start. A look at /var/log/messages should reveal the following
error:

OpenJDK Client VM warning: INFO: os::commit_memory(0xb31ab000, 163840, 1) failed; error='Permission denied' (errno=13)

The command sudo audit2allow -w -a can be used to translates the SELinux audit
messages into a description of why the access was denied.

The current solution is to enable the boolean allow_execmem. This solution is
probably too permissive and should ideally be more restrictive, for example by
targetting a single Java program.

sudo setsebool -P allow_execmem 1
getsebool -a | grep allow_execmem  # should be "on"

Restart the container (docker restart unifi-controller) and then check its logs
to check that the controller has successfully started (docker logs unifi-controller).