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Date: Fri, 13 Jan 2017 04:00:52 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Alan J. Wylie" <alan@wylie.me.uk>,
        Thorsten Leemhuis <regressions@leemhuis.info>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: 4.9.0 regression in pipe-backed iov_iter with systemd-nspawn
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On Thu, Jan 12, 2017 at 03:28:32PM -0800, Linus Torvalds wrote:
> On Thu, Jan 12, 2017 at 2:46 PM, Alan J. Wylie <alan@wylie.me.uk> wrote:
> >
> > I'm off to bed now with a stinking head cold I'm afraid.
> 
> So assuming Al hasn't figured it out by the time you get back, can you
> try to send us the same strace for the working case?

That, and check if it is reproducible on commit 523ac9afc73a with
commit 8e54cadab447 cherry-picked on top of that.