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Date:   Mon, 7 Jun 2021 10:28:37 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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        Anton Altaparmakov <anton@tuxera.com>,
        David Howells <dhowells@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Pavel Begunkov <asml.silence@gmail.com>
Subject: Re: [RFC][PATCHSET] iov_iter work
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On Sun, Jun 06, 2021 at 03:46:37PM -0700, Linus Torvalds wrote:
> And yes, I realize that 'uaccess_kernel()' is hopefully always false
> on any architectures we care about and so the compiler would just pick
> one at compile time rather than actually having both those
> initializers.
> 
> But I think that "the uaccess_kernel() KVEC case is legacy for
> architectures that haven't converted to the new world order yet" thing
> is just even more of an argument for not duplicating and writing the
> code out in full on a source level (and making that normal case be
> ".iov = iov").

It can't even happen for the legacy architectures, given that the
remaining set_fs() areas are small and never do iov_iter based I/O.