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From:   David Howells <dhowells@redhat.com>
In-Reply-To: <20230202204428.3267832-5-willy@infradead.org>
References: <20230202204428.3267832-5-willy@infradead.org> <20230202204428.3267832-1-willy@infradead.org>
To:     "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc:     dhowells@redhat.com, linux-fsdevel@vger.kernel.org,
        linux-afs@lists.infradead.org, linux-btrfs@vger.kernel.org,
        linux-ext4@vger.kernel.org, linux-mm@kvack.org,
        Hugh Dickins <hughd@google.com>, linux-kernel@vger.kernel.org,
        fstests@vger.kernel.org
Subject: Re: [PATCH 4/5] afs: Zero bytes after 'oldsize' if we're expanding the file
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Date:   Mon, 27 Feb 2023 13:49:27 +0000
Message-ID: <2730679.1677505767@warthog.procyon.org.uk>
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Matthew Wilcox (Oracle) <willy@infradead.org> wrote:

> POSIX requires that "If the file size is increased, the extended area
> shall appear as if it were zero-filled".  It is possible to use mmap to
> write past EOF and that data will become visible instead of zeroes.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

That seems to work.  Do you want me to pass it on to Linus?  If not:

Acked-by: David Howells <dhowells@redhat.com>