Troubleshooting ORA-600 [H_MK_WRITING_CR_BG] 11.2.0.3 standby instance crash

env: 11.2.0.3 RAC Dataguard ON Exadata x2, a standby instance crash, alert log show ora-600 internal error, ORA-00600: internal error code, arguments: [H_MK_WRITING_CR_BG], []