Re: 4.14 balance: kernel BUG at /home/kernel/COD/linux/fs/btrfs/ctree.c:1856!

[Tomasz Chmielewski <mangoo@wpkg.org>]

On 2017-11-18 10:08, Hans van Kranenburg wrote:
> On 11/18/2017 01:49 AM, Tomasz Chmielewski wrote:
>> I'm getting the following BUG when running balance on one of my 
>> systems:
>> 
>> 
>> [ 3458.698704] BTRFS info (device sdb3): relocating block group
>> 306045779968 flags data|raid1
>> [ 3466.892933] BTRFS info (device sdb3): found 2405 extents
>> [ 3495.408630] BTRFS info (device sdb3): found 2405 extents
>> [ 3498.161144] ------------[ cut here ]------------
>> [ 3498.161150] kernel BUG at 
>> /home/kernel/COD/linux/fs/btrfs/ctree.c:1856!
>> [ 3498.161264] invalid opcode: 0000 [#1] SMP

(...)

>> [ 3498.164523] Call Trace:
>> [ 3498.164694]  tree_advance+0x16e/0x1d0 [btrfs]
>> [ 3498.164874]  btrfs_compare_trees+0x2da/0x6a0 [btrfs]
>> [ 3498.165078]  ? process_extent+0x1580/0x1580 [btrfs]
>> [ 3498.165264]  btrfs_ioctl_send+0xe94/0x1120 [btrfs]
> 
> It's using send + balance at the same time. There's something that 
> makes
> btrfs explode when you do that.
> 
> It's not new in 4.14, I have seen it in 4.7 and 4.9 also, various
> different explosions in kernel log. Since that happened, I made sure I
> never did those two things at the same time.

Indeed, send was started when balance was running.

Thanks for the hint.


Tomasz Chmielewski
https://lxadm.com