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Date:   Thu, 31 Jan 2019 13:08:00 +0100 (CET)
From:   Jiri Kosina <jikos@kernel.org>
To:     Daniel Gruss <daniel@gruss.cc>
cc:     Vlastimil Babka <vbabka@suse.cz>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-api@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        Jann Horn <jannh@google.com>,
        Dominique Martinet <asmadeus@codewreck.org>,
        Andy Lutomirski <luto@amacapital.net>,
        Dave Chinner <david@fromorbit.com>,
        Kevin Easton <kevin@guarana.org>,
        Matthew Wilcox <willy@infradead.org>,
        Cyril Hrubis <chrubis@suse.cz>, Tejun Heo <tj@kernel.org>,
        "Kirill A . Shutemov" <kirill@shutemov.name>
Subject: Re: [PATCH 2/3] mm/filemap: initiate readahead even if IOCB_NOWAIT
 is set for the I/O
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On Thu, 31 Jan 2019, Daniel Gruss wrote:

> If I understood it correctly, this patch just removes the advantages of 
> preadv2 over mmmap+access for the attacker.

Which is the desired effect. We are not trying to solve the timing aspect, 
as I don't think there is a reasonable way to do it, is there?

-- 
Jiri Kosina
SUSE Labs