MDK:MDK-ARM-V2.50, CPU:STR71x.
I found one task A is hangging for ever(blocked waiting for a mutex named i2cMutex) but its tcb has the state=RUNNING and i2cMutex can be now used by other tasks. So at any moment,there are two tasks(one is A) have the state=RUNNING! It's really weard. Who knows why?
http://www.keil.com/forum/docs/thread15346.asp