On 01/16/2015 04:20 PM, Thomas Gleixner wrote: > On Fri, 16 Jan 2015, Michael Kerrisk (man-pages) wrote: > >> Hello Thomas, >> >> On 01/15/2015 11:23 PM, Thomas Gleixner wrote: >>> On Thu, 15 Jan 2015, Michael Kerrisk (man-pages) wrote: >>>>> [EINVAL] uaddr equal uaddr2. Requeue to same futex. >>>> >>>> ??? I added this, but does this error not occur only for PI requeues? >>> >>> It's equally wrong for normal futexes. And its actually the same code >>> checking for this for all variants. >> >> I don't understand "equally wrong" in your reply, I'm sorry. Do you >> mean: >> >> a) This error text should be there for both normal and PI requeues > > It is there for both. The requeue code has that check independent of > the requeue type (normal/pi). It never makes sense to requeue > something to itself whether normal or pi futex. We added this for PI, > because there it is harmful, but we did not special case it. So normal > futexes get the same treatment. Hello Thomas, Color me stupid, but I can't see this in futex_requeue(). Where is that check that is "independent of the requeue type (normal/pi)"? When I look through futex_requeue(), all the likely looking sources of EINVAL are governed by a check on the 'requeue_pi' argument. Thanks, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html