Methods and apparatus for tracking defective blocks such that at least
some of the defective blocks may be readily identified and tested for
usability when desirable are disclosed. According to one aspect of the
present invention, a method for identifying spare blocks within a
non-volatile memory includes subjecting at least one defective physical
block associated with the non-volatile memory to a test that is arranged
to determine if the defective physical block is usable. The method also
includes determining when the defective physical block passes the test,
and identifying the defective physical block as a usable physical block
when it is determined that the defective physical block passes the test.