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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 5 Apr 2012 14:55:29 -0700
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Subject: Re: [PATCH 6/7] mm: kill vma flag VM_EXECUTABLE
To: Matt Helsley <matthltc@us.ibm.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>,
        Cyrill Gorcunov <gorcunov@openvz.org>, Oleg Nesterov <oleg@redhat.com>,
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On Thu, Apr 5, 2012 at 2:44 PM, Matt Helsley <matthltc@us.ibm.com> wrote:
>
> I don't think the definition of an ABI is whether there's documentation
> for it. It's whether the interface is used or not. At least that's the
> impression I've gotten from reading Linus' rants over the years.

Yes.

That said, I *do* have some very dim memory of us having had real
issues with the /proc/<pid>/exe thing and having regressions due to
holding refcounts to executables that were a.out binaries and not
demand-loaded. And people wanting to unmount filesystems despite the
binaries being live.

That said, I suspect that whatever issues we used to have with that
are pretty long gone. I don't think people use non-mmap'ed binaries
any more. So I think we can try it and see. And revert if somebody
actually notices and has problems.

                    Linus