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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun, 27 Dec 2020 15:14:49 -0800
Message-ID: <CAHk-=wiXQVE_jGN0ajk+Km925WSbCL16mAZ-UXNkp+nkc1nuQw@mail.gmail.com>
Subject: Re: LXC broken with 5.10-stable?, ok with 5.9-stable (Re: Linux 5.10.3)
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Jussi Kivilinna <jussi.kivilinna@iki.fi>,
        Christoph Hellwig <hch@lst.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        stable <stable@vger.kernel.org>, lwn@lwn.net,
        Jiri Slaby <jslaby@suse.cz>
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On Sun, Dec 27, 2020 at 1:25 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
>
> Is there any point in not doing the same (scripted, obviously) for
> all instances with .read == seq_read?  IIRC, Christoph even posted
> something along those lines, but it went nowhere for some reason...

I'd rather limit splice (and kernel_read too, for that matter) as much
as possible. It was a mistake originally to allow it everywhere, and
it's come back to bite us.

So I'd rather have people notice these odd corner cases and get them
fixed one by one than just say "anything goes".

There's hopefully not any actually left anyway...

                  Linus