Subject: Re: + sys_getppid-oopses-on-debug-kernel.patch added to -mm tree
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: =?ISO-8859-1?Q?Bj=F6rn?= Steinbrink <B.Steinbrink@gmx.de>,
       linux-kernel@vger.kernel.org, dev@sw.ru, dev@openvz.org,
       stable@kernel.org
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Date: Tue, 08 Aug 2006 16:22:27 +0100
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Ar Maw, 2006-08-08 am 17:57 +0300, ysgrifennodd Muli Ben-Yehuda:
> On Tue, Aug 08, 2006 at 04:51:38PM +0200, Björn Steinbrink wrote:
> 
> > There's a note right above the function that explains it:
> >  * NOTE! This depends on the fact that even if we _do_
> >  * get an old value of "parent", we can happily dereference
> >  * the pointer (it was and remains a dereferencable kernel pointer
> >  * no matter what): we just can't necessarily trust the result
> >  * until we know that the parent pointer is valid.
> 
> Even without getting into just how ugly this is, is it really worth
> it?

It never was in my opinion but I lost that battle to Linus in 1.3.40 or
so timescales. Given how critical getppid _isnt_ I don't see the point
in being clever.
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