The mariadbd process hangs at startup when the config file my.cnf asks for server_audit to be loaded, when this plugin has already been loaded via SQL statement.

Expected behaviour

Server startup proceeds with a warning, e.g.: plugin server_audit already loaded

Actual behaviour

Server becomes unresponsive during startup. There is no error message and the process doesn't react to signals. Only kill -9 will terminate it.

Steps to reproduce

1. execute sql: INSTALL SONAME 'server_audit'
2. add lines to my.cnf:

   [mysqld]
   plugin_load_add = server_audit
   server_audit = FORCE_PLUS_PERMANENT

3. stop the server
4. (try to) start the server

Further Information

The error log shows a partial startup: "InnoDB buffer pool(s) load completed" is the last message.

When the server is run through strace, some threads repeatedly call futex(...) and receive ETIMEDOUT, others are stuck at "futex(..., FUTEX_WAIT_PRIVATE, ...", a call that never returns.