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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 4 Mar 2019 16:09:22 -0800
Message-ID: <CAHk-=wh0ikMcREn-RLh-7TEeL28wj1-bHNTRsqpW_7dPuO7cAA@mail.gmail.com>
Subject: Re: [RFC PATCH] fs: Make splice() and tee() take into account
 O_NONBLOCK flag on pipes
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Jens Axboe <axboe@kernel.dk>,
        Slavomir Kaslev <kaslevs@vmware.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
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On Mon, Mar 4, 2019 at 4:04 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> Of course, if it turns out that this breaks something that assumes
> that splice blocks purely based on the SPLICE_F_NONBLOCK flag, we'll
> have to revert it. Looking at the history of splice, it does look like
> it has always ignored O_NONBLOCK.

Note that the "arguably buggy" argument is not an actual real argument
in the presence of regressions. It's more a "I wish reality wasn't
that way" argument, but it doesn't actually _change_ reality.

Of course, in the case of sendfile() (which is where that comment is),
I don't think we ever really even tested it either way.

                 Linus