Re: Crash in __btrfs_reserve_extent

Josef Bacik
2009-08-06T18:04:32Z

On Thu, Aug 06, 2009 at 07:41:49PM +0200, Tore Anderson wrote:
> * Josef Bacik
>
> > Ooookay, now that I'm awake lets try this again :). You are right, I
> > thought it was 212GB used, not 16GB used. Something has gone
> > horribly wrong, btrfs seems to think thats all the space it can use.
> > The command you need to use is btrfs-vol -b. Please try that and see
> > if it behaves better. Before you run that please do a btrfs-show and
> > post the output, I'd like to see how big the fs thinks its supposed
> > to be.
>
> It doesn't print much of anything, I'm afraid:
>
> root@echo:~/misc/btrfs-progs-unstable# ./btrfs-show /dev/mapper/vg_echo-lv_root
> failed to read /dev/sr0
> failed to read /dev/sdf
> failed to read /dev/sde
> failed to read /dev/sdd
> failed to read /dev/sdc
> failed to read /dev/sdb
> Btrfs Btrfs v0.19
>
> Same output with btrfs-progs-0.19. The devices it's complaining about
> is a USB memory card reader and my optical drive, if I disconnect
> those from the SCSI layer the output is simply "Btrfs Btrfs v0.19".
>
> I tried to run btrfsck earlier today, but it only gave me an error
> message. Perhaps that just made things worse?
>
> I've got a btrfs-image dump that I took right after the problem showed
> for the first time (before the fsck), by the way. It's available at
> <http://greed.fud.no/hosed_rootfs.btrfsimage.Z> in case you have any
> use for it.
>

What kernel are you running? I need to get a look at what code you are on.
Thanks for the image, I'm having some trouble getting it to work, but I will let
you know what I come up with.

Josef