When check the source code for version 6.1.1, I notice in the implemen of function xTaskRemoveFromEventList(), it has following notes:
/* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED OR THE
SCHEDULER SUSPENDED. It can also be called from within an ISR. */
I think when call this fuction, if just scheduler is suspened, it is not enough, because this function access xPendingReadyList, this list is also accessed by some ISR API function.
Fortunately, in current source code, evey time xTaskRemoveFromEventList() is called, the interrupion is disabled. So here is not prolem at present. It maybe more better to change above note, so let it is more easy to understand.