Btrfs crashes in few seconds after mounting RW. If it's important: the volume was converted from ext4. "ext2_saved" subvolume still presents.
dmesg: [ 625.998387] BTRFS info (device sda1): disk space caching is enabled [ 625.998392] BTRFS: has skinny extents [ 627.727708] BTRFS: checking UUID tree [ 708.514128] ------------[ cut here ]------------ [ 708.514161] WARNING: CPU: 1 PID: 2263 at fs/btrfs/extent-tree.c:6255 __btrfs_free_extent.isra.68+0x8c8/0xd70 [btrfs]() [ 708.514164] Modules linked in: bnep bluetooth rfkill ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_broute bridge ebtable_filter ebtable_nat ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_raw ip6table_security ip6table_mangle ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_raw iptable_security iptable_mangle gpio_ich coretemp kvm_intel kvm iTCO_wdt iTCO_vendor_support snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device lpc_ich snd_pcm snd_timer ppdev snd i2c_i801 mei_me mei soundcore parport_pc parport shpchp tpm_infineon tpm_tis tpm acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace isofs squashfs btrfs xor raid6_pq i915 hid_logitech_hidpp [ 708.514277] 8021q garp stp video llc mrp i2c_algo_bit drm_kms_helper r8169 uas crc32c_intel drm serio_raw mii hid_logitech_dj usb_storage scsi_dh_rdac scsi_dh_emc scsi_dh_alua sunrpc loop [ 708.514311] CPU: 1 PID: 2263 Comm: btrfs-transacti Not tainted 4.2.3-300.fc23.x86_64 #1 [ 708.514315] Hardware name: MSI MS-7636/H55M-P31(MS-7636) , BIOS V1.9 09/14/2010 [ 708.514319] 0000000000000000 00000000f50458a6 ffff880066b03ad8 ffffffff81771fca [ 708.514326] 0000000000000000 0000000000000000 ffff880066b03b18 ffffffff8109e4a6 [ 708.514332] 0000000000000002 000000252f595000 00000000fffffffe 0000000000000000 [ 708.514338] Call Trace: [ 708.514349] [<ffffffff81771fca>] dump_stack+0x45/0x57 [ 708.514359] [<ffffffff8109e4a6>] warn_slowpath_common+0x86/0xc0 [ 708.514365] [<ffffffff8109e5da>] warn_slowpath_null+0x1a/0x20 [ 708.514391] [<ffffffffa0305628>] __btrfs_free_extent.isra.68+0x8c8/0xd70 [btrfs] [ 708.514429] [<ffffffffa036da5a>] ? find_ref_head+0x5a/0x80 [btrfs] [ 708.514456] [<ffffffffa03093c8>] __btrfs_run_delayed_refs+0x998/0x1080 [btrfs] [ 708.514477] [<ffffffffa030c674>] btrfs_run_delayed_refs.part.73+0x74/0x270 [btrfs] [ 708.514496] [<ffffffffa030c885>] btrfs_run_delayed_refs+0x15/0x20 [btrfs] [ 708.514518] [<ffffffffa0320f26>] btrfs_commit_transaction+0x56/0xad0 [btrfs] [ 708.514541] [<ffffffffa031c604>] transaction_kthread+0x214/0x230 [btrfs] [ 708.514564] [<ffffffffa031c3f0>] ? btrfs_cleanup_transaction+0x500/0x500 [btrfs] [ 708.514569] [<ffffffff810bc8a8>] kthread+0xd8/0xf0 [ 708.514574] [<ffffffff810bc7d0>] ? kthread_worker_fn+0x160/0x160 [ 708.514581] [<ffffffff81778d9f>] ret_from_fork+0x3f/0x70 [ 708.514585] [<ffffffff810bc7d0>] ? kthread_worker_fn+0x160/0x160 [ 708.514588] ---[ end trace 6731111f3bf2295a ]--- [ 708.514594] BTRFS info (device sda1): leaf 535035904 total ptrs 204 free space 4451 [ 708.514598] item 0 key (159696797696 169 0) itemoff 16250 itemsize 33 [ 708.514601] extent refs 1 gen 21134 flags 2 [ 708.514604] tree block backref root 2 [ 708.514609] item 1 key (159696830464 169 1) itemoff 16217 itemsize 33 [ 708.514612] extent refs 1 gen 21134 flags 2 [ 708.514615] tree block backref root 2 [ 708.514619] item 2 key (159696846848 169 0) itemoff 16184 itemsize 33 *********** a lot of similar messages *********** [ 708.516923] item 203 key (159711268864 169 0) itemoff 9551 itemsize 33 [ 708.516927] extent refs 1 gen 21082 flags 2 [ 708.516930] tree block backref root 384 [ 708.516937] BTRFS error (device sda1): unable to find ref byte nr 159708172288 parent 0 root 385 owner 2 offset 0 [ 708.516944] ------------[ cut here ]------------ [ 708.516975] WARNING: CPU: 1 PID: 2263 at fs/btrfs/extent-tree.c:6261 __btrfs_free_extent.isra.68+0x92f/0xd70 [btrfs]() [ 708.516979] BTRFS: Transaction aborted (error -2) [ 708.516982] Modules linked in: bnep bluetooth rfkill ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_broute bridge ebtable_filter ebtable_nat ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_raw ip6table_security ip6table_mangle ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_raw iptable_security iptable_mangle gpio_ich coretemp kvm_intel kvm iTCO_wdt iTCO_vendor_support snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device lpc_ich snd_pcm snd_timer ppdev snd i2c_i801 mei_me mei soundcore parport_pc parport shpchp tpm_infineon tpm_tis tpm acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace isofs squashfs btrfs xor raid6_pq i915 hid_logitech_hidpp [ 708.517075] 8021q garp stp video llc mrp i2c_algo_bit drm_kms_helper r8169 uas crc32c_intel drm serio_raw mii hid_logitech_dj usb_storage scsi_dh_rdac scsi_dh_emc scsi_dh_alua sunrpc loop [ 708.517108] CPU: 1 PID: 2263 Comm: btrfs-transacti Tainted: G W 4.2.3-300.fc23.x86_64 #1 [ 708.517112] Hardware name: MSI MS-7636/H55M-P31(MS-7636) , BIOS V1.9 09/14/2010 [ 708.517115] 0000000000000000 00000000f50458a6 ffff880066b03a78 ffffffff81771fca [ 708.517123] 0000000000000000 ffff880066b03ad0 ffff880066b03ab8 ffffffff8109e4a6 [ 708.517129] ffffffffa03a0349 000000252f595000 00000000fffffffe 0000000000000000 [ 708.517135] Call Trace: [ 708.517143] [<ffffffff81771fca>] dump_stack+0x45/0x57 [ 708.517150] [<ffffffff8109e4a6>] warn_slowpath_common+0x86/0xc0 [ 708.517157] [<ffffffff8109e535>] warn_slowpath_fmt+0x55/0x70 [ 708.517186] [<ffffffffa030568f>] __btrfs_free_extent.isra.68+0x92f/0xd70 [btrfs] [ 708.517226] [<ffffffffa036da5a>] ? find_ref_head+0x5a/0x80 [btrfs] [ 708.517262] [<ffffffffa03093c8>] __btrfs_run_delayed_refs+0x998/0x1080 [btrfs] [ 708.517288] [<ffffffffa030c674>] btrfs_run_delayed_refs.part.73+0x74/0x270 [btrfs] [ 708.517317] [<ffffffffa030c885>] btrfs_run_delayed_refs+0x15/0x20 [btrfs] [ 708.517351] [<ffffffffa0320f26>] btrfs_commit_transaction+0x56/0xad0 [btrfs] [ 708.517382] [<ffffffffa031c604>] transaction_kthread+0x214/0x230 [btrfs] [ 708.517411] [<ffffffffa031c3f0>] ? btrfs_cleanup_transaction+0x500/0x500 [btrfs] [ 708.517419] [<ffffffff810bc8a8>] kthread+0xd8/0xf0 [ 708.517425] [<ffffffff810bc7d0>] ? kthread_worker_fn+0x160/0x160 [ 708.517432] [<ffffffff81778d9f>] ret_from_fork+0x3f/0x70 [ 708.517439] [<ffffffff810bc7d0>] ? kthread_worker_fn+0x160/0x160 [ 708.517444] ---[ end trace 6731111f3bf2295b ]--- [ 708.517450] BTRFS: error (device sda1) in __btrfs_free_extent:6261: errno=-2 No such entry [ 708.517455] BTRFS info (device sda1): forced readonly [ 708.517464] BTRFS: error (device sda1) in btrfs_run_delayed_refs:2781: errno=-2 No such entry [ 708.517580] pending csums is 139264 [ 841.017119] BTRFS error (device sda1): cleaner transaction attach returned -30 I checked the filesystem extents: $ sudo btrfs check --subvol-extents 5 /dev/sda1 Print extent state for subvolume 5 on /dev/sda1 UUID: 6de5c663-bc65-4120-8cf6-5309fd25aa7e checksum verify failed on 159708168192 found 3659C180 wanted 8EE67C14 checksum verify failed on 159708168192 found 3659C180 wanted 8EE67C14 bytenr mismatch, want=159708168192, have=16968404070778227820 ERROR: while mapping refs: -5 extent_io.c:582: free_extent_buffer: Assertion `eb->refs < 0` failed. btrfs(+0x51e9e)[0x56283f4bde9e] btrfs(free_extent_buffer+0xc0)[0x56283f4be9b0] btrfs(btrfs_free_fs_root+0x11)[0x56283f4aef11] btrfs(rb_free_nodes+0x21)[0x56283f4d7cc1] btrfs(close_ctree+0x194)[0x56283f4b0214] btrfs(cmd_check+0x486)[0x56283f49ace6] btrfs(main+0x82)[0x56283f47fad2] /lib64/libc.so.6(__libc_start_main+0xf0)[0x7f8cbea98580] btrfs(_start+0x29)[0x56283f47fbd9] $ Will "btrfs check --repair" fix my problem or make it worse? Fedora 23. Installed (but now broken) system has 4.2.5 kernel. A live CD has kernel 4.2.3 with btrfs-progs 4.2.2! -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html