1) Check TPL<=TPL_CALLBACK prior to invoking SerialIO protocol. 2) Check TPL <= TPL_NOTIFY prior to allocate memory in datahub status code driver. 3) Add lock to prevent the critical data. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@2225 6f19259b-4bc3-4df7-8a09-765794883524