On Thu, Nov 19, 2015 at 07:47:32PM +0100, Oleg Nesterov wrote: > ptrace_attach() can hang waiting for STOPPED -> TRACED transition if the > tracee gets frozen in between, change wait_on_bit() to use TASK_KILLABLE. > > This doesn't really solve the problem(s) and we probably need to fix the > freezer. In particular, note that this means that pm freezer will fail if > it races attach-to-stopped-task. > > And otoh perhaps we can just remove JOBCTL_TRAPPING_BIT altogether, it is > not clear if we really need to hide this transition from debugger, WNOHANG > after PTRACE_ATTACH can fail anyway if it races with SIGCONT. > > Reported-by: Andrey Ryabinin <[email protected]> > Signed-off-by: Oleg Nesterov <[email protected]>
Acked-by: Tejun Heo <[email protected]> Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
