CentOS Community, Would someone who is familiar with reading boot messages and kernel errors be able to assist with advising me on what the following errors might mean in dmesg. It seems to come up randomly towards the end of the logfile. ------------[ cut here ]------------ WARNING: at arch/x86/kernel/cpu/mtrr/generic.c:467 generic_get_mtrr+0x11e/0x140() (Not tainted) Hardware name: empty mtrr: your BIOS has set up an incorrect mask, fixing it up. Modules linked in: Pid: 0, comm: swapper Not tainted 2.6.32-220.2.1.el6.x86_64 #1 Call Trace: [<ffffffff81069997>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff81069a86>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff8102713e>] ? generic_get_mtrr+0x11e/0x140 [<ffffffff81c2bfd1>] ? mtrr_cleanup+0x8c/0x3fd [<ffffffff81c2ae47>] ? get_mtrr_state+0x2ec/0x2fb [<ffffffff81c2a988>] ? mtrr_bp_init+0x1ab/0x1d2 [<ffffffff81c254d8>] ? setup_arch+0x4b8/0xaea [<ffffffff814ec4c5>] ? printk+0x41/0x44 [<ffffffff81c1fc2e>] ? start_kernel+0xdc/0x430 [<ffffffff81c1f33a>] ? x86_64_start_reservations+0x125/0x129 [<ffffffff81c1f438>] ? x86_64_start_kernel+0xfa/0x109 ---[ end trace a7919e7f17c0a725 ]--- ------------[ cut here ]------------ WARNING: at kernel/sched.c:5914 thread_return+0x232/0x79d() (Tainted: G W ---------------- ) Hardware name: empty Modules linked in: ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 raid1 e1000e serio_raw i2c_i801 i2c_core sg iTCO_wdt iTCO_vendor_support ioatdma dca i5000_edac edac_core i5k_amb shpchp ext4 mbcache jbd2 raid10 sd_mod crc_t10dif ahci pata_acpi ata_generic ata_piix dm_mirror dm_region_hash dm_log dm_mod [last unloaded: scsi_wait_scan] Pid: 5696, comm: md1_resync Tainted: G W ---------------- 2.6.32-220.2.1.el6.x86_64 #1 Call Trace: [<ffffffff81069997>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff810699ea>] ? warn_slowpath_null+0x1a/0x20 [<ffffffff814eccc5>] ? thread_return+0x232/0x79d [<ffffffffa0073654>] ? raise_barrier+0xb4/0x1e0 [raid10] [<ffffffff8105e770>] ? default_wake_function+0x0/0x20 [<ffffffffa00747d1>] ? sync_request+0x541/0xa70 [raid10] [<ffffffffa0073599>] ? raid10_unplug+0x29/0x30 [raid10] [<ffffffff813ea428>] ? is_mddev_idle+0xc8/0x120 [<ffffffff813eab6d>] ? md_do_sync+0x6ad/0xbe0 [<ffffffff813eb336>] ? md_thread+0x116/0x150 [<ffffffff813eb220>] ? md_thread+0x0/0x150 [<ffffffff810906a6>] ? kthread+0x96/0xa0 [<ffffffff8100c14a>] ? child_rip+0xa/0x20 [<ffffffff81090610>] ? kthread+0x0/0xa0 [<ffffffff8100c140>] ? child_rip+0x0/0x20 ---[ end trace a7919e7f17c0a727 ]--- md: md1: data-check done. x86 PAT enabled: cpu 0, old 0x7040600070406, new 0x7010600070106 ------------[ cut here ]------------ WARNING: at arch/x86/kernel/cpu/mtrr/generic.c:467 generic_get_mtrr+0x11e/0x140() (Not tainted) Hardware name: empty mtrr: your BIOS has set up an incorrect mask, fixing it up. Modules linked in: Pid: 0, comm: swapper Not tainted 2.6.32-220.4.1.el6.x86_64 #1 Call Trace: [<ffffffff81069a17>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff81069b06>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff8102713e>] ? generic_get_mtrr+0x11e/0x140 [<ffffffff81c2bfd1>] ? mtrr_cleanup+0x8c/0x3fd [<ffffffff81c2ae47>] ? get_mtrr_state+0x2ec/0x2fb [<ffffffff81c2a988>] ? mtrr_bp_init+0x1ab/0x1d2 [<ffffffff81c254d8>] ? setup_arch+0x4b8/0xaea [<ffffffff814ec3c6>] ? printk+0x41/0x43 [<ffffffff81c1fc2e>] ? start_kernel+0xdc/0x430 [<ffffffff81c1f33a>] ? x86_64_start_reservations+0x125/0x129 [<ffffffff81c1f438>] ? x86_64_start_kernel+0xfa/0x109 ---[ end trace a7919e7f17c0a725 ]---