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Date:   Tue, 28 Jun 2022 19:36:37 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christian Brauner <brauner@kernel.org>
Cc:     linux-fsdevel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
        Matthew Wilcox <willy@infradead.org>,
        David Howells <dhowells@redhat.com>,
        Dominique Martinet <asmadeus@codewreck.org>
Subject: Re: [PATCH 08/44] copy_page_{to,from}_iter(): switch iovec variants
 to generic
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On Tue, Jun 28, 2022 at 02:32:05PM +0200, Christian Brauner wrote:
> On Wed, Jun 22, 2022 at 05:15:16AM +0100, Al Viro wrote:
> > we can do copyin/copyout under kmap_local_page(); it shouldn't overflow
> > the kmap stack - the maximal footprint increase only by one here.
> > 
> > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> > ---
> 
> Assuming the WARN_ON(1) removals are intentional,
> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>

Deliberate - it shouldn't be any different from what _copy_to_iter() and
_copy_from_iter() are ready to handle.