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Date:   Tue, 9 Nov 2021 01:49:07 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Linux FS Devel <linux-fsdevel@vger.kernel.org>,
        Miklos Szeredi <miklos@szeredi.hu>
Subject: Re: FUSE: anyway to return different stat::st_dev inside one
 filesystem?
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On Mon, Nov 08, 2021 at 10:22:16AM +0800, Qu Wenruo wrote:
> For kernel btrfs, it's not a big deal, as we will return different
> st_dev for each subvolume.

It is a big deal, as that behavior does break things and has been the
source of constant troubnle and discussion.  It needs to be fixed in
btrfs eventually and absolutely not spread any further.