storage/maria/ma_loghandler.c:
  Fixed bug of waiting for flush pass end: in case of two sequential flushes waiting thread can not detect end of the pass it is waiting because till the time it will check the flush in progress flag will be set on again. Solution is to have pass number and compare the number before before waits start and check it as condition of the flush pass end (of course it does not matter if the counter of pass number overflows).