Re: read-only subvolumes?

[Andreas Philipp <philipp.andreas@gmail.com>]

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On 23.03.2011 11:07, Andreas Philipp wrote:
>
> On 23.03.2011 10:25, Li Zefan wrote:
>>> Hi all,
>>>
>>> When I am creating subvolumes I get this strange behavior. If I
>>> create a subvolume with a name longer than 4 characters it is
>>> read-only, if the name is shorter than 5 characters the
>>> subvolume is writeable as expected. I think it is since I
>>> upgraded to kernel version 2.6.38 (I do not create subvolumes
>>> on a regular basis.). I will compile one of the latest 2.6.37
>>> kernels to see whether there the problem exists, too. Another
>>> interesting point is that previously created subvolumes are
>>> not affected.
>>>
>>> Thanks, Andreas Philipp
>>>
>>> thor btrfs # btrfs subvolume create 123456789 Create subvolume
>>> './123456789' thor btrfs # touch 123456789/lsdkfj touch:
>>> cannot touch `123456789/lsdkfj': Read-only file system
>
>> This is really odd, but I can't reproduce it.
>
>> I created a btrfs filesystem on 2.6.37 kernel, and rebooted to
>> latest 2.6.38+, and tried the procedures as you did, but nothing
>> bad happend.
> While playing around I found the following three new points: - Now
> the length of the subvolume name does not matter. So even the ones
> with short names are read-only. - It also happens to a fresh newly
> created btrfs filesystem. - If I take a snapshot of an "old" (=
> writeable) subvolume this is writeable.
>
> I will now reboot into 2.6.37.4, check there, and then report
> back.

Well, this was fast. Everything works as expected on 2.6.37.4. See the
output of uname -a for the exact kernel version below.
I will now reboot into a differently configured kernel version 2.6.38
and look whether the problem is gone there.

Thanks,
Andreas Philipp

thor ~ # uname -a
Linux thor 2.6.37.4 #2 SMP Wed Mar 23 10:25:54 CET 2011 x86_64
Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz GenuineIntel GNU/Linux
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