On 05/01, Peter Zijlstra wrote: > > The only code I found that seems to care is ptrace_attach(), where we > wait for JOBCTL_TRAPPING to get cleared. That same function has a > comment about hiding the STOPPED -> RUNNING -> TRACED transition. So I'm > assuming it needs to observe TRACED if it observes !TRAPPING.
Yes, exactly. > But I don't think there's enough barriers on that end to guarantee this. > Any ->state load after wait_on_bit() is, afact, free to have happened > before the ->jobctl load. do_wait() does set_current_state() before it checks ->state or anything else. Oleg.
