From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Albert Cahalan" <acahalan@gmail.com>
Subject: Re: [RFC/PATCH] revoke/frevoke system calls
Date: Mon, 7 Aug 2006 11:19:47 -0400
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To: "Pekka Enberg" <penberg@cs.helsinki.fi>
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On 8/7/06, Pekka Enberg <penberg@cs.helsinki.fi> wrote:
> [Albert Cahalan]
>> Edgar Toernig writes:

> > > Urgs, so any user may remove mappings from another process and
> > > let it crash?
> > Two good solutions come to mind:
> >
> > a. substitute the zero page
> > b. make the mapping private and touch it as if C-O-W happened
>
> Actually, I think revokeat() and frevoke() should be consistent with
> mmap which will make a process go SIGBUS if it attempts to write to
> truncated shared mapping.

You're right. Apps must already be tolerant of SIGBUS.
There is thus no additional risk.