I get these frequently -- here's the untainted first one: [ 4.747356] ------------[ cut here ]------------ [ 4.747377] WARNING: CPU: 3 PID: 439 at fs/btrfs/ctree.h:1559 btrfs_update_device+0x1c5/0x1d0 [btrfs] [ 4.747377] Modules linked in: nfs_acl lockd grace sunrpc ip_tables btrfs xor raid6_pq sd_mod crc32c_intel firewire_ohci igb ahci firewire_core crc_itu_t dca libahci i915 libata i2c_algo_bit e1000e drm_kms_helper ptp syscopyarea sysfillrect pps_core sysimgblt f b_sys_fops drm video [ 4.747385] CPU: 3 PID: 439 Comm: btrfs-cleaner Not tainted 4.13.2-1.el7.elrepo.x86_64 #1 [ 4.747385] Hardware name: Supermicro X10SAE/X10SAE, BIOS 2.0a 05/09/2014 [ 4.747386] task: ffff88040cdcae80 task.stack: ffffc900021f4000 [ 4.747396] RIP: 0010:btrfs_update_device+0x1c5/0x1d0 [btrfs] [ 4.747396] RSP: 0018:ffffc900021f7d00 EFLAGS: 00010206 [ 4.747397] RAX: 0000000000000fff RBX: ffff880407b7aa80 RCX: 0000001bc6c71e00 [ 4.747397] RDX: ffff880000000000 RSI: ffff880404cd3f3c RDI: ffff880409417b58 [ 4.747398] RBP: ffffc900021f7d48 R08: 0000000000003f60 R09: ffffc900021f7cb8 [ 4.747398] R10: 0000000000001000 R11: 0000000000000003 R12: ffff88040559f800 [ 4.747398] R13: 0000000000000000 R14: ffff880409417b58 R15: 0000000000003f3c [ 4.747399] FS: 0000000000000000(0000) GS:ffff88041fac0000(0000) knlGS:0000000000000000 [ 4.747399] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.747400] CR2: 00007f29c3000248 CR3: 00000004056a4000 CR4: 00000000001406e0 [ 4.747400] Call Trace: [ 4.747410] btrfs_remove_chunk+0x2fb/0x8b0 [btrfs] [ 4.747418] btrfs_delete_unused_bgs+0x363/0x440 [btrfs] [ 4.747426] cleaner_kthread+0x150/0x180 [btrfs] [ 4.747429] kthread+0x109/0x140 [ 4.747436] ? btree_invalidatepage+0xa0/0xa0 [btrfs] [ 4.747437] ? kthread_park+0x60/0x60 [ 4.747439] ret_from_fork+0x25/0x30 [ 4.747439] Code: 10 00 00 00 4c 89 fe e8 8a 30 ff ff 4c 89 f7 e8 32 f6 fc ff e9 d3 fe ff ff b8 f4 ff ff ff e9 d4 fe ff ff 0f 1f 00 e8 bb 2e 9e e0 <0f> ff eb af 0f 1f 80 00 00 00 00 0f 1f 44 00 00 55 31 d2 be 02 [ 4.747450] ---[ end trace 1ef80a625983d73b ]--- I've recently done a rebalance as well as scrubs. As well as mount -oremount,clear_cache $mountpoint ...and then a fresh reboot to get an untainted trace. I'm running mainline kernel 4.13.2-1.el7.elrepo.x86_64 I don't see any side effects from this ... just frequent dmesg messages.
I also did a btrfs check --repair on all the fs's -- the trace still occurs dozens of times a day.
Per the mailing list, this was due to the size not being a multiple of 4k. I used "btrfs fi show --raw /mnt" to see the size in bytes, and then ... sudo btrfs filesystem resize N:SIZE /mnt Where N was the disk number in the "btrfs fi show" output, and SIZE was the rounded down number of bytes that was a multiple of 4k. Qu Wenro says this would work as well: > btrfs fi resize N:max <path> > > Or > > btrfs fi resize N:-1 <path> > > The first one will resize the devid N to its max size. > The 2nd one will resize the devid N to current size - 1 (byte). > > Both will go through shrink routine, which will do the round_down. Not closing because there was some discussion on the list between Qu and nborisov@suse.de about changing the error message or removing it or...?
Hit by this too... Device added some time ago ( 4.12 epoch) btrfs fi resize 5:max seems to have fixed it. (original size was not a multiple of 4k) For the sake of completeness, my backtrace: [147466.798669] ------------[ cut here ]------------ [147466.798687] WARNING: CPU: 0 PID: 7595 at fs/btrfs/ctree.h:1559 btrfs_update_device+0x1b3/0x1c0 [147466.798690] Modules linked in: rfcomm cmac tun nls_iso8859_1 nls_cp437 vfat fat ctr ccm 8021q garp mrp bridge stp llc nft_reject_ipv4 nft_limit nf_conntrack_ipv6 nf_defrag_ipv6 nft_ct nft_rejec t_inet nf_reject_ipv4 nft_reject_ipv6 nf_reject_ipv6 nft_reject nft_masq_ipv4 nf_nat_masquerade_ipv4 nft_masq nft_counter nfnetlink_log nft_log nft_meta nft_set_bitmap nft_set_hash nft_set_rbtree $ ft_chain_nat_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_tables_inet nf_tables_ipv6 nf_tables_ipv4 bnep radeon ath9k_htc i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_s$ s_fops ttm drm sch_fq_codel kvm_amd nf_conntrack_netlink nft_nat nf_nat kvm tpm_tis tpm_tis_core irqbypass pcspkr k10temp ath3k btusb nf_conntrack tpm btrtl btintel i2c_piix4 bluetooth nf_tables d$ bg input_leds ecdh_generic [147466.798760] crc16 evdev snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel xhci_pci xhci_hcd nfnetlink acpi_cpufreq serio nfsd snd_hda_codec button snd_hwdep video a$ th_rpcgss snd_hda_core oid_registry snd_pcm snd_timer snd lockd soundcore grace bonding arc4 ath9k ath9k_common ath9k_hw led_class mac80211 ath cfg80211 rfkill nct6775 hwmon_vid hwmon imon(O) si21$ 7(O) si2168(O) tbsecp3(O) tas2101(O) i2c_mux dvb_usb_af9015(O) dvb_usb_v2(O) dvb_usb_m920x(O) dvb_usb(O) dvb_core(O) rc_core(O) media(O) i2c_core dm_crypt algif_skcipher hid_generic usbhid hid crc$ 10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel aes_x86_64 crypto_simd glue_helper cryptd alx mdio ohci_pci ehci_pci ohci_hcd ehci_hcd usbcore usb_common sunrpc dm_mod dax [147466.798835] CPU: 0 PID: 7595 Comm: btrfs Tainted: G W O 4.13.3-gentoo #1 [147466.798839] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./FM2A88X-ITX+, BIOS P3.40 01/14/2016 [147466.798843] task: ffff92459c3f8f00 task.stack: ffffaf3985794000 [147466.798849] RIP: 0010:btrfs_update_device+0x1b3/0x1c0 [147466.798852] RSP: 0018:ffffaf3985797710 EFLAGS: 00010206 [147466.798856] RAX: 0000000000000fff RBX: 0000000000000000 RCX: 000001d1c0e11e00 [147466.798859] RDX: 0000000000000004 RSI: 0000000000003e36 RDI: ffff92447dda9c70 [147466.798862] RBP: ffffaf3985797758 R08: 0000000000003e3a R09: ffffaf39857976c8 [147466.798865] R10: 0000000000001000 R11: 0000000000000003 R12: ffff924813d3a770 [147466.798868] R13: ffff9248199b8800 R14: 0000000000003e16 R15: ffff92447dda9c70 [147466.798872] FS: 00007f3bba7118c0(0000) GS:ffff92482ec00000(0000) knlGS:0000000000000000 [147466.798875] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [147466.798878] CR2: 00007f4f226260b0 CR3: 00000002bf8ae000 CR4: 00000000000406f0 [147466.798880] Call Trace: [147466.798888] btrfs_finish_chunk_alloc+0x126/0x4f0 [147466.798895] ? btrfs_insert_item+0x80/0xf0 [147466.798901] btrfs_create_pending_block_groups+0x12f/0x240 [147466.798906] __btrfs_end_transaction+0x8d/0x2d0 [147466.798911] btrfs_end_transaction+0x10/0x18 [147466.798915] __btrfs_prealloc_file_range+0x34e/0x460 [147466.798921] btrfs_prealloc_file_range+0x13/0x18 [147466.798926] prealloc_file_extent_cluster+0x129/0x238 [147466.798931] relocate_file_extent_cluster+0x7f/0x3d0 [147466.798936] relocate_block_group+0x54c/0x670 [147466.798941] btrfs_relocate_block_group+0x184/0x230 [147466.798945] btrfs_relocate_chunk+0x36/0xc0 [147466.798948] btrfs_balance+0xa7b/0x1340 [147466.798954] ? try_to_wake_up+0x21f/0x448 [147466.798961] btrfs_ioctl_balance+0x3a0/0x3b0 [147466.798965] btrfs_ioctl+0xd81/0x2420 [147466.798971] ? tty_write_unlock+0x31/0x38 [147466.798975] ? tty_ldisc_deref+0x16/0x20 [147466.798979] ? tty_write+0x1d8/0x2f0 [147466.798984] ? n_tty_open+0xd0/0xd0 [147466.798989] do_vfs_ioctl+0xa1/0x5c8 [147466.798994] ? vfs_write+0x199/0x1b0 [147466.798999] ? hrtimer_init+0x100/0x100 [147466.799003] SyS_ioctl+0x79/0x90 [147466.799008] entry_SYSCALL_64_fastpath+0x13/0x94 [147466.799012] RIP: 0033:0x7f3bb9778ca7 [147466.799014] RSP: 002b:00007ffdfce08818 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [147466.799019] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f3bb9778ca7 [147466.799022] RDX: 00007ffdfce088b0 RSI: 00000000c4009420 RDI: 0000000000000003 [147466.799024] RBP: 0000000001f6a050 R08: 00007f3bba7118c0 R09: 00007f3bba7118c0 [147466.799027] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 [147466.799030] R13: 0000000000000001 R14: 00007f3bb9a315a0 R15: 0000000000000000 [147466.799033] Code: 00 4c 89 ff 45 31 c0 ba 10 00 00 00 4c 89 f6 e8 34 37 ff ff 4c 89 ff e8 fc 0d fd ff e9 da fe ff ff b8 f4 ff ff ff e9 da fe ff ff <0f> ff eb b8 e8 f4 a2 d8 ff 0f 1f 40 00 0f 1$ 44 00 00 55 31 d2 [147466.799084] ---[ end trace baf2843fc871fae3 ]---