linux: Btrfs goes forced readonly when qgroup already exists

[Joseph Salisbury]

On 12/23/2014 09:34 AM, Sebastiaan L. Zoutendijk wrote:
> Dear Ubuntu Kernel Team,
>
> I would like to request an upstream patch [1] to be applied to the 3.16
> kernel.  This patch prevents Btrfs filesystems from going readonly when
> a subvolume ID is reused but the corresponding qgroup wasn't destroyed
> when the original subvolume was deleted.  This patch has been applied by
> upstream to 3.17 [2], but not to 3.16 before it went EOL.  For more
> details on the bug, please have a look at the Debian bug log [3].  That
> log also contains instructions to reproduce the bug, dmesg output, and
> my tests of the patch on various kernel versions.
>
>   [1] https://patchwork.kernel.org/patch/4739211/
>   [2] https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=fe9133f10ca56e54c5f5075a802bc08e61ad8456
>   [3] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=769576
>
> [Please keep 769576-forwarded at bugs.debian.org in the CC, this will log
> your reply in the Debian bug tracker.  If you also want your reply to be
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>
Would it be possible for you to also open a bug in Launchpad for this?  
It can be done by running the following from a terminal:

ubuntu-bug linux

Thanks,

Joe