On Fri, Sep 2, 2016 at 8:35 PM, Liu Bo <bo.li.liu@xxxxxxxxxx> wrote:
> This can only happen with CONFIG_BTRFS_FS_CHECK_INTEGRITY=y.
>
> Commit 1ba98d0 ("Btrfs: detect corruption when non-root leaf has zero item")
> assumes that a leaf is its root when leaf->bytenr == btrfs_root_bytenr(root),
> however, we should not use btrfs_root_bytenr(root) since it's mainly got
> updated during committing transaction. So the check can fail when doing
> COW on this leaf while it is a root.
>
> This changes to use "if (leaf == btrfs_root_node(root))" instead, just like
> how we check whether leaf is a root in __btrfs_cow_block().
>
> Reported-by: Jeff Mahoney <jeffm@xxxxxxxx>
> Signed-off-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
Hi Bo,
Even with this patch applied against latest branch for-linus-4.8, at
least on a build with CONFIG_BTRFS_FS_CHECK_INTEGRITY=y,
the issue still happens for me when running fsstress with balance in parallel:
[ 366.998044] BTRFS: device fsid 69759b3a-96ae-467d-aa63-364144e73a28
devid 1 transid 3 /dev/sdc
[ 367.023652] BTRFS info (device sdc): turning on discard
[ 367.025036] BTRFS info (device sdc): disk space caching is enabled
[ 367.026360] BTRFS info (device sdc): has skinny extents
[ 367.069415] BTRFS info (device sdc): creating UUID tree
[ 367.133704] BTRFS info (device sdc): relocating block group 29360128 flags 36
[ 367.142196] BTRFS info (device sdc): found 2 extents
[ 367.147932] BTRFS info (device sdc): relocating block group 20971520 flags 34
[ 367.157947] BTRFS info (device sdc): found 1 extents
[ 367.162649] BTRFS info (device sdc): relocating block group 12582912 flags 1
[ 367.182872] BTRFS info (device sdc): found 1 extents
[ 367.189932] BTRFS info (device sdc): found 1 extents
[ 367.200983] BTRFS info (device sdc): relocating block group
1270874112 flags 1
[ 367.235862] BTRFS critical (device sdc): corrupt leaf, non-root
leaf's nritems is 0: block=1103937536,root=5, slot=0
[ 367.238223] BTRFS info (device sdc): leaf 1103937536 total ptrs 0
free space 3995
[ 367.239371] BTRFS: assertion failed: 0, file: fs/btrfs/disk-io.c, line: 4059
[ 367.240321] ------------[ cut here ]------------
[ 367.241245] kernel BUG at fs/btrfs/ctree.h:3367!
[ 367.241961] invalid opcode: 0000 [#1] PREEMPT SMP
[ 367.242685] Modules linked in: btrfs crc32c_generic xor raid6_pq
acpi_cpufreq tpm_tis tpm sg i2c_piix4 i2c_core psmouse ppdev processor
evdev parport_pc parport serio_raw pcspkr button loop autofs4 ext4
crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi
ata_piix libata virtio_pci virtio_ring e1000 virtio scsi_mod floppy
[last unloaded: btrfs]
[ 367.244302] CPU: 11 PID: 3451 Comm: fdm-stress Not tainted
4.7.0-rc6-btrfs-next-34+ #1
[ 367.244302] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 367.244302] task: ffff880183ef8bc0 ti: ffff880183fe0000 task.ti:
ffff880183fe0000
[ 367.244302] RIP: 0010:[<ffffffffa04601d5>] [<ffffffffa04601d5>]
assfail.constprop.42+0x1c/0x1e [btrfs]
[ 367.244302] RSP: 0018:ffff880183fe3c78 EFLAGS: 00010296
[ 367.244302] RAX: 0000000000000040 RBX: ffff880222a66ab0 RCX: 0000000000000001
[ 367.244302] RDX: ffffffff810a0a23 RSI: ffffffff814a82cb RDI: 00000000ffffffff
[ 367.244302] RBP: ffff880183fe3c78 R08: 0000000000000001 R09: 0000000000000000
[ 367.244302] R10: ffff880183fe3b70 R11: ffffffff82f3650d R12: ffff880183e8e000
[ 367.244302] R13: ffff8800b3e7d000 R14: 0000000000000a59 R15: 0000000000000017
[ 367.244302] FS: 00007f0b85310700(0000) GS:ffff88023f4c0000(0000)
knlGS:0000000000000000
[ 367.244302] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 367.244302] CR2: 00007f0b7800ea28 CR3: 000000022da9b000 CR4: 00000000000006e0
[ 367.244302] Stack:
[ 367.244302] ffff880183fe3ca0 ffffffffa03e51e3 0000000000000023
ffff880222a66ab0
[ 367.244302] ffff880183885bb8 ffff880183fe3d38 ffffffffa03c9540
0000000083fe3d08
[ 367.244302] ffff8800b3e7d2d8 0000000000001000 ffff880183fe3e7f
ffff880183ff8000
[ 367.244302] Call Trace:
[ 367.244302] [<ffffffffa03e51e3>] btrfs_mark_buffer_dirty+0xdf/0xe5 [btrfs]
[ 367.244302] [<ffffffffa03c9540>] split_leaf+0x47c/0x566 [btrfs]
[ 367.244302] [<ffffffffa03c9c09>] btrfs_search_slot+0x5df/0x755 [btrfs]
[ 367.244302] [<ffffffff8116daf7>] ? slab_post_alloc_hook+0x42/0x52
[ 367.244302] [<ffffffffa03caf5a>] btrfs_insert_empty_items+0x5d/0xa6 [btrfs]
[ 367.244302] [<ffffffffa03f783b>] btrfs_symlink+0x17f/0x34f [btrfs]
[ 367.244302] [<ffffffff8118bcf5>] vfs_symlink+0x51/0x6e
[ 367.244302] [<ffffffff8118fc4c>] SYSC_symlinkat+0x6d/0xb2
[ 367.244302] [<ffffffff8100101a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
[ 367.244302] [<ffffffff811904b6>] SyS_symlink+0x16/0x18
[ 367.244302] [<ffffffff814a88e5>] entry_SYSCALL_64_fastpath+0x18/0xa8
[ 367.244302] [<ffffffff81102507>] ? time_hardirqs_off+0x9/0x14
[ 367.244302] [<ffffffff8108f019>] ? trace_hardirqs_off_caller+0x1f/0xaa
[ 367.244302] Code: 89 83 88 00 00 00 31 c0 5b 41 5c 41 5d 5d c3 55
89 f1 48 c7 c2 14 8b 46 a0 48 89 fe 48 c7 c7 27 8c 46 a0 48 89 e5 e8
e5 2f cc e0 <0f> 0b 55 89 f1 48 c7 c2 03 a2 46 a0 48 89 fe 48 c7 c7 dc
a3 46
[ 367.244302] RIP [<ffffffffa04601d5>] assfail.constprop.42+0x1c/0x1e [btrfs]
[ 367.244302] RSP <ffff880183fe3c78>
[ 367.289039] ---[ end trace a3e4ce9819ed383b ]---
thanks
> ---
> fs/btrfs/disk-io.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 9367c31..b401e6d 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -572,13 +572,17 @@ static noinline int check_leaf(struct btrfs_root *root,
> * open_ctree() some roots has not yet been set up.
> */
> if (!IS_ERR_OR_NULL(check_root)) {
> + struct extent_buffer *eb;
> +
> + eb = btrfs_root_node(check_root);
> /* if leaf is the root, then it's fine */
> - if (leaf->start !=
> - btrfs_root_bytenr(&check_root->root_item)) {
> + if (leaf != eb) {
> CORRUPT("non-root leaf's nritems is 0",
> - leaf, root, 0);
> + leaf, check_root, 0);
> + free_extent_buffer(eb);
> return -EIO;
> }
> + free_extent_buffer(eb);
> }
> return 0;
> }
> --
> 2.5.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Filipe David Manana,
"People will forget what you said,
people will forget what you did,
but people will never forget how you made them feel."
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
