kernel bug msg when doing a btrfs balance

[Karsten Schurig]

amd64-microcode is installed.

Ubuntu 3.5.0-23.35-generic 3.5.7.2

dmemsg output:

[ 693.130413] ------------[ cut here ]------------
[ 693.130509] kernel BUG at /build/buildd/linux-3.5.0/fs/btrfs/relocation.c:2278!
[ 693.130645] invalid opcode: 0000 [#1] SMP
[ 693.130744] CPU 0
[ 693.130787] Modules linked in: sp5100_tco kvm_amd kvm psmouse k10temp serio_raw i2c_piix4 radeon ext2 ttm drm_kms_helper drm i2c_algo_bit mac_hid lp parport btrfs zlib_deflate libcrc32c hid_generic usbhid hid pata_atiixp r8169 microcode
[ 693.131415]
[ 693.131430] Pid: 2384, comm: btrfs Tainted: G W 3.5.0-23-generic #35-Ubuntu To Be Filled By O.E.M. To Be Filled By O.E.M./E350M1
[ 693.131678] RIP: 0010:[<ffffffffa00da3e2>] [<ffffffffa00da3e2>] merge_reloc_roots+0x142/0x150 [btrfs]
[ 693.131901] RSP: 0018:ffff88012315da58 EFLAGS: 00010286
[ 693.132004] RAX: 00000000ffffffe2 RBX: ffff88004ef5f000 RCX: 00000000ffffffe2
[ 693.132137] RDX: 0000000000000001 RSI: ffffffffa00ef050 RDI: ffff880138f04000
[ 693.132270] RBP: ffff88012315da88 R08: 0000000000000000 R09: ffff88013ec1b660
[ 693.132402] R10: ffffffffa006aaea R11: ffffffffa007e900 R12: ffff880134ce6000
[ 693.132535] R13: ffff88012315da58 R14: ffff880134ce6590 R15: ffff880134ce6000
[ 693.132669] FS: 00007f904729e740(0000) GS:ffff88013ec00000(0000) knlGS:0000000000000000
[ 693.132818] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 693.132927] CR2: 00007f3f2ce4c050 CR3: 00000001286a2000 CR4: 00000000000007f0
[ 693.133059] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 693.133193] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 693.133326] Process btrfs (pid: 2384, threadinfo ffff88012315c000, task ffff8801391ac500)
[ 693.133474] Stack:
[ 693.133519] ffff88012315da58 ffff88012315da58 00000000ffffffe2 ffff880134ce6020
[ 693.133689] ffff880134ce60e8 ffff88012e424510 ffff88012315db18 ffffffffa00da89d
[ 693.133859] ffff88012315db18 ffff88012315dae0 0000000000000001 00000000ffffffe4
[ 693.134029] Call Trace:
[ 693.134127] [<ffffffffa00da89d>] relocate_block_group+0x26d/0x690 [btrfs]
[ 693.134300] [<ffffffffa00dae6f>] btrfs_relocate_block_group+0x1af/0x2e0 [btrfs]
[ 693.134482] [<ffffffffa00b7165>] btrfs_relocate_chunk.isra.53+0x75/0x720 [btrfs]
[ 693.134663] [<ffffffffa00c60d8>] ? btrfs_set_lock_blocking_rw+0xa8/0xf0 [btrfs]
[ 693.134809] [<ffffffff81082203>] ? __wake_up+0x53/0x70
[ 693.134953] [<ffffffffa00aedc9>] ? release_extent_buffer.isra.38+0x79/0xe0 [btrfs]
[ 693.135138] [<ffffffffa00b3f07>] ? free_extent_buffer+0x37/0x90 [btrfs]
[ 693.135306] [<ffffffffa00bb397>] __btrfs_balance+0x427/0x7f0 [btrfs]
[ 693.135470] [<ffffffffa00bbad4>] btrfs_balance+0x374/0x550 [btrfs]
[ 693.135630] [<ffffffffa00c02d4>] btrfs_ioctl_balance+0x124/0x460 [btrfs]
[ 693.135765] [<ffffffff816838de>] ? _raw_spin_lock+0xe/0x20
[ 693.135913] [<ffffffffa00c55b9>] btrfs_ioctl+0x1049/0x12d0 [btrfs]
[ 693.136039] [<ffffffff8114b1d9>] ? handle_mm_fault+0x259/0x320
[ 693.136158] [<ffffffff8132f960>] ? rb_insert_color+0x110/0x150
[ 693.136276] [<ffffffff8168754c>] ? do_page_fault+0x1cc/0x4e0
[ 693.136392] [<ffffffff8114eb5f>] ? vma_link+0xcf/0xe0
[ 693.136497] [<ffffffff81193d19>] do_vfs_ioctl+0x99/0x590
[ 693.136607] [<ffffffff8116df80>] ? kmem_cache_free+0x20/0x100
[ 693.136723] [<ffffffff811942a9>] sys_ioctl+0x99/0xa0
[ 693.136828] [<ffffffff8168bb69>] system_call_fastpath+0x16/0x1b
[ 693.136941] Code: f9 ff ff 85 c0 74 97 0f 0b 85 d2 0f 85 08 ff ff ff 49 83 bc 24 80 05 00 00 00 75 15 48 83 c4 10 31 c0 5b 41 5c 41 5d 41 5e 5d c3 <0f> 0b 0f 0b 0f 0b 0f 0b 66 0f 1f 44 00 00 55 48 89 e5 41 57 41
[ 693.137853] RIP [<ffffffffa00da3e2>] merge_reloc_roots+0x142/0x150 [btrfs]
[ 693.138034] RSP <ffff88012315da58>
[ 693.138146] ---[ end trace 9311971051c0a78e ]---

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1130539

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.8 kernel[0] (Not a kernel in the daily directory) and install both the linux-image and linux-image-extra .deb packages.

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.8-raring/

[Karsten Schurig (theemerald)]

I installed the kernel you suggested and started a btrfs balance process.

Linux version 3.8.0-030800-generic (root@gomeisa) (gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5) ) #201302181935 SMP Tue Feb 19 00:36:19 UTC 2013

The bug I reported did not occur again.
Besides that i got rid of alot other problems too:
- no more "no space left" errors
- no more "cache entry did not match inode cache .." warnings
- remaining space on HDDs is shown correctly
- data went from metadata chunks to data chunks as it should on btrfs balance, now total data in metadata chunks is a bit about a gigabyte which seems much more realistic to me than ~500GB.

So I resume that the bug is fixed in the upstream kernel but
another bug occured where should I report it ?
Shall I link it to this report ?