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Date: Fri, 16 Jan 2015 16:20:50 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
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Subject: Re: futex(2) man page update help request
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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.

Thanks,

	tglx