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Date:   Thu, 19 Aug 2021 00:24:47 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Sidong Yang <realwakka@gmail.com>
Cc:     linux-btrfs <linux-btrfs@vger.kernel.org>
Subject: Re: [PATCH] btrfs: reflink: Assure length != 0 in btrfs_extent_same()
Message-ID: <20210818222447.GX5047@twin.jikos.cz>
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On Wed, Aug 18, 2021 at 04:08:15PM +0000, Sidong Yang wrote:
> btrfs_extent_same() cannot be called with zero length. Because when
> length is zero, it would be filtered by condition in
> btrfs_remap_file_range(). But if this function is used in other case in
> future, it can make ret as uninitialized.

Do you have a specific future in mind? Adding the assert won't hurt so
ok.