kernel BUG at /build/buildd/linux-3.0.0/fs/btrfs/extent-tree.c:5510

[nomike]

My netbook does not boot anymore. In recovery mode when I select to do a fsck I get this kernel error message:

---SNIP---
[ 90.988538] ------------[ cut here ]------------
[ 90.988609] kernel BUG at /build/buildd/linux-3.0.0/fs/btrfs/extent-tree.c:5510!
[ 90.988695] invalid opcode: 0000 [#1] SMP
[ 90.988812] Modules linked in: btrfs zlib_deflate libcrc32c i915 drm_kms_helper drm i2c_algo_bit r8169 video
[ 90.989194]
[ 90.989249] Pid: 284, comm: btrfs-transacti Not tainted 3.0.0-13-generic #22-Ubuntu Dell Inc. Inspiron 1011/CN0Y53
[ 90.989432] EIP: 0060:[<f81d4a6e>] EFLAGS: 00010282 CPU: 1
[ 90.989522] EIP is at alloc_reserved_tree_block+0x1be/0x1f0 [btrfs]
[ 90.989588] EAX: ffffffef EBX: f4ff2150 ECX: 00000000 EDX: 00000008
[ 90.989654] ESI: f509c000 EDI: e4dd1000 EBP: f4ac5e08 ESP: f4ac5dc8
[ 90.989719] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[ 90.989784] Process btrfs-transacti (pid: 284, ti=f4ac4000 task=f4ae8cc0 task.ti=f4ac4000)
[ 90.989869] Stack:
[ 90.989922] f4ac5e5f f4ac5df8 00000001 a0000000 00000566 00000000 00000000 00000000
[ 90.990240] 00000000 f50d2000 e4dd1000 00000000 00000033 f491d3c0 f50d2000 e4dd1000
[ 90.990557] f4ac5e7c f81d5287 00000000 00000000 00000002 00000000 00000000 00000000
[ 90.990875] Call Trace:
[ 90.990958] [<f81d5287>] run_delayed_tree_ref+0xd7/0x220 [btrfs]
[ 90.991048] [<f81d8414>] run_one_delayed_ref+0xc4/0x120 [btrfs]
[ 90.991138] [<f81d8516>] run_clustered_refs+0xa6/0x1e0 [btrfs]
[ 90.991227] [<f81d8702>] btrfs_run_delayed_refs+0xb2/0x1d0 [btrfs]
[ 90.991299] [<c152c80d>] ? _raw_spin_lock+0xd/0x10
[ 90.991388] [<f81e8c96>] btrfs_commit_transaction+0x96/0x720 [btrfs]
[ 90.991481] [<f81e96c5>] ? start_transaction.part.22+0x65/0x270 [btrfs]
[ 90.991552] [<c1066320>] ? add_wait_queue+0x50/0x50
[ 90.991643] [<f81e9908>] ? start_transaction+0x38/0x50 [btrfs]
[ 90.991733] [<f81e24bd>] transaction_kthread+0x20d/0x220 [btrfs]
[ 90.991802] [<c102f9ce>] ? complete+0x4e/0x60
[ 90.991888] [<f81e22b0>] ? btrfs_congested_fn+0x90/0x90 [btrfs]
[ 90.991956] [<c1065b1d>] kthread+0x6d/0x80
[ 90.992011] [<c1065ab0>] ? flush_kthread_worker+0x80/0x80
[ 90.992011] [<c1533ebe>] kernel_thread_helper+0x6/0x10
[ 90.992011] Code: 5f 5d c3 66 90 89 fa 89 f0 b9 b0 00 00 00 e8 aa df 02 00 8b 45 10 8b 55 14 89 04 24 89 f0 89 54 24 04 89 fa e8 74 e1 02 00 eb 86 <0f> 0b 0f 0b 8b 4d 28 8b 41 09 8b 51 0d 89 44 24 0c 89 54 24 10
[ 90.992011] EIP: [<f81d4a6e>] alloc_reserved_tree_block+0x1be/0x1f0 [btrfs] SS:ESP 0068:f4ac5dc8
[ 90.994568] ---[ end trace 733a0abd0ec10c9f ]---
---SNAP---

I have an etx3 /boot partition, a btrfs "/" partition with a subvolume "@" and a btrfs "/home/" partition with a subvolume "@home" and AFAIR "/dev/sda7" is "/".

Find attached the whole output of dmesg.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Typhoe (spamistrash)]

Hi,

got this bug this morning too....

Kernel BUG at/build/buildd/linux-3.5.0/fs/btrfs/extent-tree.c:6109!
I'm using kernel 3.5.0-14-generic on a Dell Optiflex 780

I can't get any access back to my system...
I was using a / and a /home in btrfs both.

Trying to boot on a usb key doesn't help because the kernel detects the hard drive and try to also access the btrfs filesystem and crash...

Regards

[Rolf Leggewie (r0lf)]

Ubuntu has not shipped a btrfs package for a long time, moving to generic Ubuntu for triage.

This bug is pretty old. Did anyone affected by this experience it with trusty or later? Sounds like filesystem corruption (btrfs was still very unstable and considered unsafe to use for real data back in 2012!)

[Rolf Leggewie (r0lf)]

We'd like to figure out what's causing this bug for you, but we haven't heard back from you in a while. Could you please provide the requested information? Thanks!

[Rolf Leggewie (r0lf)]

Closing as obsolete/unreproducible