On Sat, 3 Jun 2017, Thomas Gleixner wrote:

If the to be woken task has state TASK_TRACED then the wakeup state check
should not match. But for some stupid reason wake_up_lock_sleeper() should
not use TASK_ALL. The lock sleepers are in state UNINTERRUPTIBLE, so the
wake state should be UNINTERRUPTIBLE as well.

The extra check in try_to_wake_up() should stay though as it prevents
spurious wake ups in general.

Further experimentation shows that it's not worth it. I'll send a V2 of
that patch with the proper fix.

Thanks,

	tglx