As you know minifilter support beautiful lfc communication channel for user mode comm. My question is can we use this mechanism for process callback notify routine to send process detail usermode. Like usermode app wait kernel mode message(filtergetmessage) and inside minifilter we have ProcessCreateNotifyRoutine(PsSetCreateProcessNotifyRoutine) and when new process create(before created) we call FltSendMessage to usermode app and wait ReplyMessage to block or allow process ? If Yes What happen when new process created? Imagine process A created and minifilter send process detail to usermode app and wait reply while it Process B created.Can there will be problem? Can we use some of Sync menchanism? Like guard mutex apin or etc?