I am running a database workload with 2.8.32.2 This is a modern 2 socket Intel box. 8 cpus 64gb mem, decent sized SAN. There are 18 separate filesystems on 18 luns in this configuration. I just picked up 2 warnings (I don't think any IO failed) and thought I would pass them along. ------------[ cut here ]------------ WARNING: at fs/btrfs/extent-tree.c:5695 btrfs_alloc_free_block+0x180/0x350 [btrfs]() Hardware name: System x3550 M2 -[7946AC1]- Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf xt_physdev ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 btrfs zlib_deflate libcrc32c ext3 jbd dm_mirror dm_region_hash dm_log dm_mod kvm_intel kvm cdc_ether usbnet mii pcspkr serio_raw i2c_i801 i2c_core iTCO_wdt iTCO_vendor_support shpchp ioatdma dca i7core_edac edac_core sg bnx2 ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix mptsas mptscsih mptbase scsi_transport_sas lpfc scsi_transport_fc scsi_tgt [last unloaded: microcode] Pid: 5618, comm: btrfs-endio-wri Not tainted 2.6.38.2 #2 Call Trace: [<ffffffff8106157f>] ? warn_slowpath_common+0x7f/0xc0 [<ffffffff810615da>] ? warn_slowpath_null+0x1a/0x20 [<ffffffffa0340060>] ? btrfs_alloc_free_block+0x180/0x350 [btrfs] [<ffffffffa036b720>] ? map_extent_buffer+0xb0/0xc0 [btrfs] [<ffffffffa036c428>] ? read_extent_buffer+0xd8/0x1d0 [btrfs] [<ffffffffa032b12d>] ? __btrfs_cow_block+0x14d/0x5f0 [btrfs] [<ffffffffa0347c60>] ? btrfs_buffer_uptodate+0x50/0x70 [btrfs] [<ffffffffa032b6d7>] ? btrfs_cow_block+0x107/0x1f0 [btrfs] [<ffffffffa0331844>] ? btrfs_search_slot+0x544/0x8a0 [btrfs] [<ffffffffa034266d>] ? btrfs_lookup_file_extent+0x3d/0x40 [btrfs] [<ffffffffa0329eea>] ? btrfs_alloc_path+0x1a/0x30 [btrfs] [<ffffffffa035b295>] ? btrfs_drop_extents+0xf5/0xa40 [btrfs] [<ffffffff810d2017>] ? rb_reserve_next_event+0x67/0x470 [<ffffffffa036cdde>] ? set_extent_bit+0x11e/0x4f0 [btrfs] [<ffffffff8113ed06>] ? kmem_cache_alloc+0x186/0x190 [<ffffffffa034f8d3>] ? insert_reserved_file_extent.clone.0+0x73/0x240 [btrfs] [<ffffffffa036d4e8>] ? lock_extent_bits+0x88/0xb0 [btrfs] [<ffffffffa035126e>] ? btrfs_endio_direct_write+0x1de/0x2c0 [btrfs] [<ffffffff8117d80d>] ? bio_endio+0x1d/0x40 [<ffffffffa034ec87>] ? btrfs_end_dio_bio+0x47/0xb0 [btrfs] [<ffffffff8117d80d>] ? bio_endio+0x1d/0x40 [<ffffffffa0346054>] ? end_workqueue_fn+0xf4/0x130 [btrfs] [<ffffffffa037887e>] ? worker_loop+0x13e/0x540 [btrfs] [<ffffffffa0378740>] ? worker_loop+0x0/0x540 [btrfs] [<ffffffffa0378740>] ? worker_loop+0x0/0x540 [btrfs] [<ffffffff810826f6>] ? kthread+0x96/0xa0 [<ffffffff8100cdc4>] ? kernel_thread_helper+0x4/0x10 [<ffffffff81082660>] ? kthread+0x0/0xa0 [<ffffffff8100cdc0>] ? kernel_thread_helper+0x0/0x10 ---[ end trace 848fd7559197ef2d ]--- ------------[ cut here ]------------ WARNING: at fs/btrfs/extent-tree.c:5695 btrfs_alloc_free_block+0x180/0x350 [btrfs]() Hardware name: System x3550 M2 -[7946AC1]- Modules linked in: autofs4 sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf xt_physdev ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 btrfs zlib_deflate libcrc32c ext3 jbd dm_mirror dm_region_hash dm_log dm_mod kvm_intel kvm cdc_ether usbnet mii pcspkr serio_raw i2c_i801 i2c_core iTCO_wdt iTCO_vendor_support shpchp ioatdma dca i7core_edac edac_core sg bnx2 ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix mptsas mptscsih mptbase scsi_transport_sas lpfc scsi_transport_fc scsi_tgt [last unloaded: microcode] Pid: 5618, comm: btrfs-endio-wri Tainted: G W 2.6.38.2 #2 Call Trace: [<ffffffff8106157f>] ? warn_slowpath_common+0x7f/0xc0 [<ffffffff810615da>] ? warn_slowpath_null+0x1a/0x20 [<ffffffffa0340060>] ? btrfs_alloc_free_block+0x180/0x350 [btrfs] [<ffffffffa036c428>] ? read_extent_buffer+0xd8/0x1d0 [btrfs] [<ffffffffa032b12d>] ? __btrfs_cow_block+0x14d/0x5f0 [btrfs] [<ffffffffa032b6d7>] ? btrfs_cow_block+0x107/0x1f0 [btrfs] [<ffffffffa03308ea>] ? push_leaf_right+0x14a/0x1a0 [btrfs] [<ffffffffa036b720>] ? map_extent_buffer+0xb0/0xc0 [btrfs] [<ffffffffa0331164>] ? split_leaf+0x724/0x8c0 [btrfs] [<ffffffffa0329d2b>] ? generic_bin_search+0x19b/0x210 [btrfs] [<ffffffffa032ba33>] ? leaf_space_used+0xf3/0x130 [btrfs] [<ffffffffa037d450>] ? btrfs_wake_function+0x0/0x20 [btrfs] [<ffffffffa032c12a>] ? btrfs_leaf_free_space+0x8a/0xe0 [btrfs] [<ffffffffa0331a8f>] ? btrfs_search_slot+0x78f/0x8a0 [btrfs] [<ffffffffa035b964>] ? btrfs_drop_extents+0x7c4/0xa40 [btrfs] [<ffffffffa0332bcd>] ? btrfs_insert_empty_items+0x8d/0xf0 [btrfs] [<ffffffffa036cdde>] ? set_extent_bit+0x11e/0x4f0 [btrfs] [<ffffffffa034f912>] ? insert_reserved_file_extent.clone.0+0xb2/0x240 [btrfs] [<ffffffffa036d4e8>] ? lock_extent_bits+0x88/0xb0 [btrfs] [<ffffffffa035126e>] ? btrfs_endio_direct_write+0x1de/0x2c0 [btrfs] [<ffffffff8117d80d>] ? bio_endio+0x1d/0x40 [<ffffffffa034ec87>] ? btrfs_end_dio_bio+0x47/0xb0 [btrfs] [<ffffffff8117d80d>] ? bio_endio+0x1d/0x40 [<ffffffffa0346054>] ? end_workqueue_fn+0xf4/0x130 [btrfs] [<ffffffffa037887e>] ? worker_loop+0x13e/0x540 [btrfs] [<ffffffffa0378740>] ? worker_loop+0x0/0x540 [btrfs] [<ffffffffa0378740>] ? worker_loop+0x0/0x540 [btrfs] [<ffffffff810826f6>] ? kthread+0x96/0xa0 [<ffffffff8100cdc4>] ? kernel_thread_helper+0x4/0x10 [<ffffffff81082660>] ? kthread+0x0/0xa0 [<ffffffff8100cdc0>] ? kernel_thread_helper+0x0/0x10 ---[ end trace 848fd7559197ef2e ]---
Closing, if this is still affecting you on a newer kernel please reopen.