Date: Thu, 10 Aug 2017 15:06:45 +0200
From: Michal Hocko <mhocko@kernel.org>
To: Florian Weimer <fweimer@redhat.com>
Cc: riel@redhat.com, linux-kernel@vger.kernel.org, mike.kravetz@oracle.com,
        linux-mm@kvack.org, colm@allcosts.net, akpm@linux-foundation.org,
        keescook@chromium.org, luto@amacapital.net, wad@chromium.org,
        mingo@kernel.org, kirill@shutemov.name, dave.hansen@intel.com,
        linux-api@vger.kernel.org
Subject: Re: [PATCH v2 0/2] mm,fork,security: introduce MADV_WIPEONFORK
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On Mon 07-08-17 16:19:18, Florian Weimer wrote:
> On 08/07/2017 03:46 PM, Michal Hocko wrote:
> > How do they know that they need to regenerate if they do not get SEGV?
> > Are they going to assume that a read of zeros is a "must init again"? Isn't
> > that too fragile?
> 
> Why would it be fragile?  Some level of synchronization is needed to set
> things up, of course, but I think it's possible to write a lock-free
> algorithm to maintain the state even without strong guarantees of memory
> ordering from fork.

Yeah, that is what I meant as fragile... I am not question this is
impossible.
-- 
Michal Hocko
SUSE Labs