linux-kernel - overlayfs: upperdir and workdir on same mount but different btrfs subvolume

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Message-ID: <3838dcffca05b126f590acc1bf1733b7@myjm.de>
Date:	Tue, 28 Apr 2015 17:20:08 +0200
From:	Michael Göhler <visit@...m.de>
To:	linux-kernel@...r.kernel.org
Subject: overlayfs: upperdir and workdir on same mount but different btrfs
 subvolume

Hi,

think I found a small issue in overlayfs (kernel 4.0.0).

If I mount an overlay and specify two different subvolumes from the same 
btrfs
mount point, I don't get the expected:
overlayfs: workdir and upperdir must reside under the same mount

But any write operation on files from lowerdir fails with:
Invalid cross-device link

--
Michael Göhler
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