Comment 19 for bug 713769

This happens frequently:

Aug 12 13:42:41 Kontor kernel: [17097.148266] ------------[ cut here ]------------
Aug 12 13:42:41 Kontor kernel: [17097.148308] kernel BUG at /build/buildd/linux-2.6.38/fs/btrfs/extent-tree.c:5512!
Aug 12 13:42:41 Kontor kernel: [17097.148354] invalid opcode: 0000 [#1] SMP
Aug 12 13:42:41 Kontor kernel: [17097.148404] last sysfs file: /sys/devices/system/cpu/cpu1/cache/index1/shared_cpu_map
Aug 12 13:42:41 Kontor kernel: [17097.148454] Modules linked in: snd_seq_dummy nls_utf8 isofs binfmt_misc parport_pc ppdev snd_hda_codec_analog snd_hda_intel snd_hda_codec snd_usb_audio snd_pcm snd_hwdep snd_usbmidi_lib snd_seq_midi rndis_wlan snd_rawmidi snd_seq_midi_event cfg80211 rndis_host snd_seq i915 cdc_ether gspca_sn9c20x psmouse gspca_main usbnet videodev drm_kms_helper snd_timer asus_atk0110 snd_seq_device drm serio_raw snd i2c_algo_bit video soundcore snd_page_alloc lp parport usbhid hid usb_storage uas btrfs zlib_deflate libcrc32c
Aug 12 13:42:41 Kontor kernel: [17097.148816]
Aug 12 13:42:41 Kontor kernel: [17097.148829] Pid: 1652, comm: btrfs-transacti Not tainted 2.6.38-10-generic #46-Ubuntu System manufacturer System Product Name/P5L8L-SE
Aug 12 13:42:41 Kontor kernel: [17097.148913] EIP: 0060:[<f82765d0>] EFLAGS: 00010282 CPU: 1
Aug 12 13:42:41 Kontor kernel: [17097.148961] EIP is at alloc_reserved_tree_block.clone.61+0x1c0/0x1f0 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149004] EAX: fffffffb EBX: f4bf4930 ECX: fffffffb EDX: f4bf4930
Aug 12 13:42:41 Kontor kernel: [17097.149041] ESI: e744c000 EDI: d959de6f EBP: d959de18 ESP: d959ddd4
Aug 12 13:42:41 Kontor kernel: [17097.149078] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Aug 12 13:42:41 Kontor kernel: [17097.149111] Process btrfs-transacti (pid: 1652, ti=d959c000 task=e91c9940 task.ti=d959c000)
Aug 12 13:42:41 Kontor kernel: [17097.149159] Stack:
Aug 12 13:42:41 Kontor kernel: [17097.149172] d959de6f d959de08 00000001 00000001 00000400 00000000 00000000 00000000
Aug 12 13:42:41 Kontor kernel: [17097.149234] 00000000 e923b114 f37fc750 d959de84 f5902fe0 00000033 00000000 f37fc750
Aug 12 13:42:41 Kontor kernel: [17097.149297] e923b000 d959de8c f8276ddb 00000000 00000000 00000005 00000000 00000000
Aug 12 13:42:41 Kontor kernel: [17097.149360] Call Trace:
Aug 12 13:42:41 Kontor kernel: [17097.149388] [<f8276ddb>] run_delayed_tree_ref+0xdb/0x230 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149436] [<f827ac74>] run_one_delayed_ref+0xc4/0x120 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149478] [<c1276ae4>] ? rb_erase+0xb4/0x120
Aug 12 13:42:41 Kontor kernel: [17097.149516] [<f827ad7a>] run_clustered_refs+0xaa/0x1f0 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149563] [<f827af6a>] btrfs_run_delayed_refs+0xaa/0x1d0 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149616] [<f82a8cec>] ? btrfs_run_ordered_operations+0x1ac/0x1c0 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149672] [<f82893c9>] btrfs_commit_transaction+0x69/0x700 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149714] [<c15088e9>] ? mutex_lock+0x19/0x40
Aug 12 13:42:41 Kontor kernel: [17097.149745] [<c106d4d0>] ? autoremove_wake_function+0x0/0x50
Aug 12 13:42:41 Kontor kernel: [17097.149792] [<f8283ec7>] transaction_kthread+0x217/0x230 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.149832] [<c1038dde>] ? complete+0x4e/0x60
Aug 12 13:42:41 Kontor kernel: [17097.151595] [<f8283cb0>] ? transaction_kthread+0x0/0x230 [btrfs]
Aug 12 13:42:41 Kontor kernel: [17097.152013] [<c106cf64>] kthread+0x74/0x80
Aug 12 13:42:41 Kontor kernel: [17097.152013] [<c106cef0>] ? kthread+0x0/0x80
Aug 12 13:42:41 Kontor kernel: [17097.156159] [<c100367e>] kernel_thread_helper+0x6/0x10
Aug 12 13:42:41 Kontor kernel: [17097.156159] Code: c3 66 90 8b 55 ec 89 f0 b9 b0 00 00 00 e8 f9 c4 02 00 8b 55 14 8b 45 10 89 54 24 04 8b 55 ec 89 04 24 89 f0 e8 c2 c6 02 00 eb 8b <0f> 0b 0f 0b 8b 47 09 8b 57 0d 89 44 24 0c 89 54 24 10 8b 07 8b
Aug 12 13:42:41 Kontor kernel: [17097.156159] EIP: [<f82765d0>] alloc_reserved_tree_block.clone.61+0x1c0/0x1f0 [btrfs] SS:ESP 0068:d959ddd4
Aug 12 13:42:42 Kontor kernel: [17097.223894] ---[ end trace 89fc6a83554f7d09 ]---