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Date:   Sat, 14 Aug 2021 01:57:31 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: [PATCH v1 0/7] Remove in-tree usage of MAP_DENYWRITE
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On Fri, Aug 13, 2021 at 02:58:57PM -1000, Linus Torvalds wrote:
> On Fri, Aug 13, 2021 at 2:54 PM Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > And nobody really complained when we weakened it, so maybe removing it
> > entirely might be acceptable.
> 
> I guess we could just try it and see... Worst comes to worst, we'll
> have to put it back, but at least we'd know what crazy thing still
> wants it..

Umm...  I'll need to go back and look through the thread, but I'm
fairly sure that there used to be suckers that did replacement of
binary that way (try to write, count on exclusion with execve while
it's being written to) instead of using rename.  Install scripts
of weird crap and stuff like that...