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Subject: Re: bind mounts on btrfs cause mountinfo confusion
To: Duncan <1i5t5.duncan@cox.net>, linux-btrfs@vger.kernel.org
References: <CAJCQCtT=-YoFJgEo=BFqfiPdtMoJCYR3dJPSekf+HQ22GYGztw@mail.gmail.com>
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From: Andrei Borzenkov <arvidjaar@gmail.com>
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Date: Tue, 18 Jul 2017 21:57:40 +0300
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18.07.2017 10:24, Duncan пишет:
> 
> Before the kernel started printing that subvol= stuff, this information 
> was missing, as it still is for non-btrfs.
> 

Huh?

tail -1 /proc/self/mountinfo

215 25 8:4 /tmp/from /tmp/to rw,relatime shared:1 - ext4 /dev/sda4
rw,errors=remount-ro,data=ordered

You just need to look in the right place ...