Unable to boot btrfs filesystem, and btrfsck aborts

Unable to boot btrfs filesystem, and btrfsck aborts

[Matthew Booth]

My laptop crashed hard earlier today. It reset immediately to a black
screen followed by the BIOS. I have no idea why.

However, it now fails to boot. I took a picture of the kernel panic
that results from trying to mount the root filesystem:
https://plus.google.com/107763699965053810188/posts/QZZt7GYzBZi

To make things worse, btrfsck aborts with a double free, without
fixing it. I took a picture of that, too:
https://plus.google.com/107763699965053810188/posts/gKYqGgFhWyT

As the kernel panic mentions btrfs_remove_free_space, I also tried
mounting with clear_cache. Unfortunately it didn't dislodge anything.

This is on a fully updated Fedora 18 system. I would really like to
get this data back. If anybody could offer a suggestion I'd be very
grateful.

Thanks,

Matt

Re: Unable to boot btrfs filesystem, and btrfsck aborts

[Harald Glatt]

On Mon, Mar 11, 2013 at 11:44 PM, Matthew Booth <matthew@heisenbug.com> wrote:
> My laptop crashed hard earlier today. It reset immediately to a black
> screen followed by the BIOS. I have no idea why.
>
> However, it now fails to boot. I took a picture of the kernel panic
> that results from trying to mount the root filesystem:
> https://plus.google.com/107763699965053810188/posts/QZZt7GYzBZi
>
> To make things worse, btrfsck aborts with a double free, without
> fixing it. I took a picture of that, too:
> https://plus.google.com/107763699965053810188/posts/gKYqGgFhWyT
>
> As the kernel panic mentions btrfs_remove_free_space, I also tried
> mounting with clear_cache. Unfortunately it didn't dislodge anything.
>
> This is on a fully updated Fedora 18 system. I would really like to
> get this data back. If anybody could offer a suggestion I'd be very
> grateful.
>
> Thanks,
>
> Matt
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

If you can make a complete image backup of the drive before trying any
things to bring it back.
Try mounting with -o nospace_cache, also try -o ro and -o recovery as
well as -o recovery,ro.

If you can bringt it back in ro mode you can at least copy your data
out of it if all else fails...

I'm not a dev, just a random guy having an interest in btrfs, so if
you don't have a backup and aren't able to create a dd copy of it
right now you might wanna wait for a reply of someone who actually
knows the code...

Good luck

Re: Unable to boot btrfs filesystem, and btrfsck aborts

[Jan Steffens]

On Mon, Mar 11, 2013 at 11:49 PM, Harald Glatt <mail@hachre.de> wrote:
> On Mon, Mar 11, 2013 at 11:44 PM, Matthew Booth <matthew@heisenbug.com> wrote:
>> My laptop crashed hard earlier today. It reset immediately to a black
>> screen followed by the BIOS. I have no idea why.
>>
>> However, it now fails to boot. I took a picture of the kernel panic
>> that results from trying to mount the root filesystem:
>> https://plus.google.com/107763699965053810188/posts/QZZt7GYzBZi
>>
>> To make things worse, btrfsck aborts with a double free, without
>> fixing it. I took a picture of that, too:
>> https://plus.google.com/107763699965053810188/posts/gKYqGgFhWyT
>>
>> As the kernel panic mentions btrfs_remove_free_space, I also tried
>> mounting with clear_cache. Unfortunately it didn't dislodge anything.
>>
>> This is on a fully updated Fedora 18 system. I would really like to
>> get this data back. If anybody could offer a suggestion I'd be very
>> grateful.
> If you can make a complete image backup of the drive before trying any
> things to bring it back.
> Try mounting with -o nospace_cache, also try -o ro and -o recovery as
> well as -o recovery,ro.

I think the bug happens during log recovery, so btrfs-zero-log might
get it mountable again, with the caveat of losing the most recently
fsynced changes.

Re: Unable to boot btrfs filesystem, and btrfsck aborts

[Harald Glatt]

If you are going to use btrfs-zero-log please create a btrfs-image
first that you can then upload to a bug report so that this can be
fixed.

# btrfs-image -c 9 -t 8 /dev/yourbtrfs /tmp/fs_image

On Mon, Mar 11, 2013 at 11:53 PM, Jan Steffens <jan.steffens@gmail.com> wrote:
> On Mon, Mar 11, 2013 at 11:49 PM, Harald Glatt <mail@hachre.de> wrote:
>> On Mon, Mar 11, 2013 at 11:44 PM, Matthew Booth <matthew@heisenbug.com> wrote:
>>> My laptop crashed hard earlier today. It reset immediately to a black
>>> screen followed by the BIOS. I have no idea why.
>>>
>>> However, it now fails to boot. I took a picture of the kernel panic
>>> that results from trying to mount the root filesystem:
>>> https://plus.google.com/107763699965053810188/posts/QZZt7GYzBZi
>>>
>>> To make things worse, btrfsck aborts with a double free, without
>>> fixing it. I took a picture of that, too:
>>> https://plus.google.com/107763699965053810188/posts/gKYqGgFhWyT
>>>
>>> As the kernel panic mentions btrfs_remove_free_space, I also tried
>>> mounting with clear_cache. Unfortunately it didn't dislodge anything.
>>>
>>> This is on a fully updated Fedora 18 system. I would really like to
>>> get this data back. If anybody could offer a suggestion I'd be very
>>> grateful.
>> If you can make a complete image backup of the drive before trying any
>> things to bring it back.
>> Try mounting with -o nospace_cache, also try -o ro and -o recovery as
>> well as -o recovery,ro.
>
> I think the bug happens during log recovery, so btrfs-zero-log might
> get it mountable again, with the caveat of losing the most recently
> fsynced changes.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: Unable to boot btrfs filesystem, and btrfsck aborts

[Josef Bacik]

On Mon, Mar 11, 2013 at 04:44:58PM -0600, Matthew Booth wrote:
> My laptop crashed hard earlier today. It reset immediately to a black
> screen followed by the BIOS. I have no idea why.
> 
> However, it now fails to boot. I took a picture of the kernel panic
> that results from trying to mount the root filesystem:
> https://plus.google.com/107763699965053810188/posts/QZZt7GYzBZi
> 
> To make things worse, btrfsck aborts with a double free, without
> fixing it. I took a picture of that, too:
> https://plus.google.com/107763699965053810188/posts/gKYqGgFhWyT
> 
> As the kernel panic mentions btrfs_remove_free_space, I also tried
> mounting with clear_cache. Unfortunately it didn't dislodge anything.
> 
> This is on a fully updated Fedora 18 system. I would really like to
> get this data back. If anybody could offer a suggestion I'd be very
> grateful.
>

This is fixed in 3.9, I'll send those patches back to -stable, sorry I should
have done that before now.  If you can't get a 3.9 kernel to boot then just use
btrfs-zero-log and you'll be good to go.  Thanks,

Josef