[Btrfs-users] Requirements for btrfs

[Marco Gruss]

Chris,

thanks for your quick reply.

Chris Mason wrote:
 > Yes, you'll need something around 2.6.20 or so to compile without any
 > patches.  I'd suggest 2.6.22.  Please keep in mind that things are very
 > alpha right now, it should only be used for experimentation.
I upgraded to 2.6.21.6 this evening and I'm now trying to break btrfs :)

This is what I have produced so far, compiling my kernel on a new
subvolume:

Aug 10 23:15:16 athlon kernel: BUG: at /tmp/btrfs-0.6/tree-defrag.c:107 defrag_walk_down()
Aug 10 23:15:16 athlon kernel:
Aug 10 23:15:16 athlon kernel: Call Trace:
Aug 10 23:15:16 athlon kernel:  [<ffffffff8862568d>] :btrfs:defrag_walk_down+0x33d/0x350
Aug 10 23:15:16 athlon kernel:  [<ffffffff88625931>] :btrfs:btrfs_defrag_leaves+0x161/0x200
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861f22c>] :btrfs:btrfs_defrag_dirty_roots+0xfc/0x180
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861f8e0>] :btrfs:btrfs_transaction_cleaner+0x0/0x160
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861f988>] :btrfs:btrfs_transaction_cleaner+0xa8/0x160
Aug 10 23:15:16 athlon kernel:  [<ffffffff80242f2d>] run_workqueue+0xad/0x160
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246f00>] keventd_create_kthread+0x0/0x90
Aug 10 23:15:16 athlon kernel:  [<ffffffff80243138>] worker_thread+0x158/0x1a0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8022b960>] default_wake_function+0x0/0x10
Aug 10 23:15:16 athlon kernel:  [<ffffffff8022b960>] default_wake_function+0x0/0x10
Aug 10 23:15:16 athlon kernel:  [<ffffffff80242fe0>] worker_thread+0x0/0x1a0
Aug 10 23:15:16 athlon kernel:  [<ffffffff80242fe0>] worker_thread+0x0/0x1a0
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246ec2>] kthread+0x92/0xd0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8020a868>] child_rip+0xa/0x12
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246f00>] keventd_create_kthread+0x0/0x90
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246e30>] kthread+0x0/0xd0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8020a85e>] child_rip+0x0/0x12
Aug 10 23:15:16 athlon kernel:
Aug 10 23:15:16 athlon kernel: ------------[ cut here ]------------
Aug 10 23:15:16 athlon kernel: kernel BUG at /tmp/btrfs-0.6/extent-tree.c:1347!
Aug 10 23:15:16 athlon kernel: invalid opcode: 0000 [1] SMP
Aug 10 23:15:16 athlon kernel: CPU 1
Aug 10 23:15:16 athlon kernel: Modules linked in: truecrypt btrfs crc32c libcrc32c jfs nls_base cast6 twofish twofish_common serpent nvidia(P) snd_seq snd_pcm_oss snd_mixer_oss snd_via82xx snd_ac97_codec ac97_bus snd_pcm snd_timer snd_page_alloc snd_mpu401_uart snd_rawmidi snd_seq_device snd sha512 sha256 sha1 aes sata_via
Aug 10 23:15:16 athlon kernel: Pid: 9183, comm: btrfs/1 Tainted: P       2.6.21.6 #1
Aug 10 23:15:16 athlon kernel: RIP: 0010:[<ffffffff8861af7f>]  [<ffffffff8861af7f>] :btrfs:btrfs_alloc_extent+0x1ef/0x2a0
Aug 10 23:15:16 athlon kernel: RSP: 0000:ffff8100788ffb20  EFLAGS: 00010286
Aug 10 23:15:16 athlon kernel: RAX: 00000000ffffffe4 RBX: ffff8100788ffbf0 RCX: 000000000000003f
Aug 10 23:15:16 athlon kernel: RDX: 0000000000000009 RSI: ffff81005937e740 RDI: 000000000005937e
Aug 10 23:15:16 athlon kernel: RBP: ffff81006dfe8800 R08: ffff8100788ffa2c R09: ffff81006851b200
Aug 10 23:15:16 athlon kernel: R10: 0000000000000000 R11: 0000000000000000 R12: ffff81004a592790
Aug 10 23:15:16 athlon kernel: R13: ffff810008659600 R14: 0000000000017f59 R15: 0000000000000001
Aug 10 23:15:16 athlon kernel: FS:  00002af7fb929090(0000) GS:ffff81007e218dc0(0000) knlGS:00000000f73f96c0
Aug 10 23:15:16 athlon kernel: CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
Aug 10 23:15:16 athlon kernel: CR2: 0000000000ccf000 CR3: 0000000000201000 CR4: 00000000000006e0
Aug 10 23:15:16 athlon kernel: Process btrfs/1 (pid: 9183, threadinfo ffff8100788fe000, task ffff810073ed0ee0)
Aug 10 23:15:16 athlon kernel: Stack:  0000000000017f59 ffff8100788ffb60 0000000000017f58 0000000000000001
Aug 10 23:15:16 athlon kernel:  0000000000000000 ffffffff806695c0 ffff81006851b200 0000000000000008
Aug 10 23:15:16 athlon kernel:  0000000000192ff5 0000000121000000 0000000000000000 ffffffff80232b9f
Aug 10 23:15:16 athlon kernel: Call Trace:
Aug 10 23:15:16 athlon kernel:  [<ffffffff80232b9f>] release_console_sem+0xaf/0xd0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861b078>] :btrfs:btrfs_alloc_free_block+0x48/0xf0
Aug 10 23:15:16 athlon kernel:  [<ffffffff886143d6>] :btrfs:__btrfs_cow_block+0xa6/0x2b0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861493e>] :btrfs:btrfs_realloc_node+0x21e/0x270
Aug 10 23:15:16 athlon kernel:  [<ffffffff88625566>] :btrfs:defrag_walk_down+0x216/0x350
Aug 10 23:15:16 athlon kernel:  [<ffffffff88625931>] :btrfs:btrfs_defrag_leaves+0x161/0x200
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861f22c>] :btrfs:btrfs_defrag_dirty_roots+0xfc/0x180
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861f8e0>] :btrfs:btrfs_transaction_cleaner+0x0/0x160
Aug 10 23:15:16 athlon kernel:  [<ffffffff8861f988>] :btrfs:btrfs_transaction_cleaner+0xa8/0x160
Aug 10 23:15:16 athlon kernel:  [<ffffffff80242f2d>] run_workqueue+0xad/0x160
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246f00>] keventd_create_kthread+0x0/0x90
Aug 10 23:15:16 athlon kernel:  [<ffffffff80243138>] worker_thread+0x158/0x1a0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8022b960>] default_wake_function+0x0/0x10
Aug 10 23:15:16 athlon kernel:  [<ffffffff8022b960>] default_wake_function+0x0/0x10
Aug 10 23:15:16 athlon kernel:  [<ffffffff80242fe0>] worker_thread+0x0/0x1a0
Aug 10 23:15:16 athlon kernel:  [<ffffffff80242fe0>] worker_thread+0x0/0x1a0
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246ec2>] kthread+0x92/0xd0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8020a868>] child_rip+0xa/0x12
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246f00>] keventd_create_kthread+0x0/0x90
Aug 10 23:15:16 athlon kernel:  [<ffffffff80246e30>] kthread+0x0/0xd0
Aug 10 23:15:16 athlon kernel:  [<ffffffff8020a85e>] child_rip+0x0/0x12
Aug 10 23:15:16 athlon kernel:
Aug 10 23:15:16 athlon kernel:
Aug 10 23:15:16 athlon kernel: Code: 0f 0b eb fe 4c 01 bd 70 02 00 00 48 8d 4c 24 60 41 b8 0c 00
Aug 10 23:15:16 athlon kernel: RIP  [<ffffffff8861af7f>] :btrfs:btrfs_alloc_extent+0x1ef/0x2a0
Aug 10 23:15:16 athlon kernel:  RSP <ffff8100788ffb20>


Afterwards, the process that triggered the bug of course hang:
10691 ?        D      0:00 ld -m elf_x86_64 -o .tmp_vmlinux1 -T arch/x86_64/kernel/vmlinux.lds arch/x86_64/kernel/head.o blah blah blah

The file system wasn't exactly full:

/dev/sda4             6.3G  1.2G  5.2G  19% /btrfstest

Any process trying to access anything on the file system (even
under /default or other subvolumes) hangs, too.


Hoping this is of some use
Marco