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Date:   Tue, 3 Nov 2020 20:02:53 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Christoph Hellwig <hch@lst.de>, Al Viro <viro@zeniv.linux.org.uk>,
        Greg KH <gregkh@linuxfoundation.org>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: support splice reads on seq_file based procfs files
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References: <20201029100950.46668-1-hch@lst.de> <20201103184815.GA24136@lst.de> <CAHk-=wha+F9-my8=3KO7TNJ7r-fVobMrXRdUuSs5c2bbqk1edA@mail.gmail.com>
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On Tue, Nov 03, 2020 at 10:57:10AM -0800, Linus Torvalds wrote:
> On Tue, Nov 3, 2020 at 10:48 AM Christoph Hellwig <hch@lst.de> wrote:
> >
> > ping?
> 
> It looked fine by me, although honestly, I'd prefer that last patch to
> be the minimum possible if we want this for 5.10.
> 
> Yeah, that might technically be just cpuinfo, but I'd be ok with the
> other read-only core proc files (ie I would *not* add it to anything
> that has a .proc_write operation like the ones in proc_net.c).
> 
> IOW, I'd start with just cpuinfo_proc_ops, proc_seq_ops,
> proc_single_ops, and stat_proc_ops.

I think Greg reported another test case hitting /proc/version

> 
> Because honestly, I'd rather restrict splice() as much as possible
> than try to say "everything should be able to do splice".

sure.