Re: [PATCH 1/1] btrfs: btrfs_calc_avail_data_space cope with no read/write devices V2

Li Zefan
2011-11-29T01:24:13Z

Andy Whitcroft wrote:
> On Mon, Nov 28, 2011 at 06:11:06AM -0600, Jonathan Nieder wrote:
>> Hi,
>>
>> Andy Whitcroft wrote:
>>
>>> When we mount a btrfs filesystem from read-only media there will be no
>>> read/write devices; for example mounting an SD card with its lock enabled.
>>> This triggers an immediate BUG during mount:
>>>
>>> kernel BUG at .../fs/btrfs/super.c:984!
>> [...]
>>> BugLink: http://bugs.launchpad.net/bugs/816770
>>> Signed-off-by: Andy Whitcroft <apw@canonical.com>
>>> ---
>>
>> Fixes http://bugs.debian.org/649847
>> Tested-by: Ivan Vilata i Balaguer <ivan@selidor.net>
>>
>> This patch fixes a regression introduced by 6d07bcec969a ("btrfs: fix
>> wrong free space information of btrfs"), which hit mainline in
>> v2.6.38-rc1. Josef Bacik acked the patch, but I can't seem to find it
>> in linux-next, linux-btrfs, or Josef's btrfs-work tree. Maybe it was
>> just forgotten.
>>
>> What can I do to help this patch get unstuck?
>
> I had completely forgotten about this one. I wonder where it did get
> to. I seem to remember testing this in house successfully.
>

This patch has the same problem with your previous one, that it will set
f_bavail to 0. I've sent out a new patch yesterday.