linux-kernel - Re: [PATCH v1 0/7] Remove in-tree usage of MAP

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Message-ID: <CAHk-=wiJ0u33h2CXAO4b271Diik=z4jRt64=Gt6YV2jV4ef27g@mail.gmail.com>
Date:   Fri, 13 Aug 2021 14:54:43 -1000
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     Andy Lutomirski <luto@...nel.org>
Cc:     "Eric W. Biederman" <ebiederm@...ssion.com>,
        David Laight <David.Laight@...lab.com>,
        David Hildenbrand <david@...hat.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
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Subject: Re: [PATCH v1 0/7] Remove in-tree usage of MAP_DENYWRITE

On Fri, Aug 13, 2021 at 2:49 PM Andy Lutomirski <luto@...nel.org> wrote:
>
> I’ll bite.  How about we attack this in the opposite direction: remove the deny write mechanism entirely.

I think that would be ok, except I can see somebody relying on it.

It's broken, it's stupid, but we've done that ETXTBUSY for a _loong_ time.

But you are right that we have removed parts of it over time (no more
MAP_DENYWRITE, no more uselib()) so that what we have today is a
fairly weak form of what we used to do.

And nobody really complained when we weakened it, so maybe removing it
entirely might be acceptable.

              Linus