Re: [PATCH] Btrfs: fix leaf corruption after __btrfs_drop_extents

["Holger Hoffstätte" <holger.hoffstaette@googlemail.com>]

On Fri, 06 Jun 2014 14:25:58 +0800, Liu Bo wrote:

> Several reports about leaf corruption has been floating on the list, one
> of them points to __btrfs_drop_extents(), and we find that the leaf
> becomes corrupted after __btrfs_drop_extents(), it's really a rare case
> but it does exist.

Out of curiosity ("..what could go wrong?" :) I applied this to 3.14.6, 
rebooted and worked a bit on my btrfs drive - rsyncs, create & delete 
snapshots etc. For the first time in ages I got two kernel messages:

Jun  6 09:20:56 tux kernel: BTRFS error (device sdb1): block group 
351872745472 has wrong amount of free space
Jun  6 09:20:56 tux kernel: BTRFS error (device sdb1): failed to load 
free space cache for block group 351872745472

I remounted without inode_cache & clear_cache, worked some more and so 
far no more messages. Could the messages be related to this patch? Or am 
I just looking at a coincidental/unrelated occurrence? Dropping the 
snapshots correctly freed up several GBs, so I assume that extents were 
dropped..

thanks
Holger