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Re: splice vs execve lockdep trace.

To: Dave Chinner <david@xxxxxxxxxxxxx>
Subject: Re: splice vs execve lockdep trace.
From: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Date: Wed, 17 Jul 2013 09:03:11 -0700
Cc: Ben Myers <bpm@xxxxxxx>, Peter Zijlstra <peterz@xxxxxxxxxxxxx>, Oleg Nesterov <oleg@xxxxxxxxxx>, Linux Kernel <linux-kernel@xxxxxxxxxxxxxxx>, Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>, Dave Jones <davej@xxxxxxxxxx>, xfs@xxxxxxxxxxx
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On Tue, Jul 16, 2013 at 10:51 PM, Dave Chinner <david@xxxxxxxxxxxxx> wrote:
>
> But When i say "stale data" I mean that the data being returned
> might not have originally belonged to the underlying file you are
> reading.

We're still talking at cross purposes then.

How the hell do you handle mmap() and page faulting?

Because if you return *that* kind of stale data, than you're horribly
horribly buggy. And you cannot *possibly* blame
generic_file_splice_read() on that.

                  Linus

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