SQL> connect / as sysdba
Connected.
SQL> SHUTDOWN ABORT
ORACLE instance shut down.
SQL> STARTUP
ORACLE instance started.

Total System Global Area  603979776 bytes
Fixed Size                  1260292 bytes
Variable Size             192939260 bytes
Database Buffers          406847488 bytes
Redo Buffers                2932736 bytes
Database mounted.
ORA-01172: recovery of thread 1 stuck at block 89 of file 2
ORA-01151: use media recovery to recover block, restore backup if needed