There is an issue with the rapidrecovery kernel module which causes a warning and backtrace in the systemlogs on unaligned partitions at the end of the snapshot process:
Apr 2 04:08:12 my-hostname kernel: rapidrecovery-vss: /dev/dm-0 [253:0]: Update metadata
Apr 2 04:08:12 my-hostname kernel: rapidrecovery-vss: /dev/dm-0 [253:0]: snapshot available at sbd0
Apr 2 04:08:12 my-hostname kernel: rapidrecovery-vss: /dev/dm-0 [253:0]: Reset metadata
Apr 2 04:08:13 my-hostname kernel: rapidrecovery-vss: /dev/sda1 [8:1]: Update metadata
Apr 2 04:08:13 my-hostname kernel: rapidrecovery-vss: /dev/sda1 [8:1]: snapshot available at sbd1
Apr 2 04:08:13 my-hostname kernel: rapidrecovery-vss: /dev/sda1 [8:1]: Reset metadata
Apr 2 04:08:13 my-hostname kernel: rapidrecovery-vss: /dev/sdb1 [8:17]: Update metadata
Apr 2 04:08:13 my-hostname kernel: rapidrecovery-vss: /dev/sdb1 [8:17]: snapshot available at sbd2
Apr 2 04:08:13 my-hostname kernel: rapidrecovery-vss: /dev/sdb1 [8:17]: Reset metadata
Apr 2 04:08:13 my-hostname kernel: ------------[ cut here ]------------
Apr 2 04:08:13 my-hostname kernel: WARNING: at /var/lib/dkms/rapidrecovery-vss/6.1.1.137/build/src/kernel/blksnap-tree.c:59 z8ce79d63e6+0x36b/0x390 [rapidrecovery_vss]() (Tainted: P W -- ------------ )
Apr 2 04:08:13 my-hostname kernel: Hardware name: Virtual Machine
Apr 2 04:08:13 my-hostname kernel: Modules linked in: rapidrecovery_vss(P)(U) nbd(U) nfsd exportfs autofs4 nfs lockd fscache auth_rpcgss nfs_acl sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 hv_netvsc hv_utils microcode joydev i2c_piix4 i2c_core sg ext4 jbd2 mbcache sr_mod cdrom pata_acpi ata_generic ata_piix sd_mod crc_t10dif hyperv_keyboard hid_hyperv hv_storvsc hyperv_fb hv_vmbus dm_mirror dm_region_hash dm_log dm_mod [last unloaded: speedstep_lib]
Apr 2 04:08:13 my-hostname kernel: Pid: 58628, comm: cow-bio-8:16 Tainted: P W -- ------------ 2.6.32-642.15.1.el6.x86_64 #1
Apr 2 04:08:13 my-hostname kernel: Call Trace:
Apr 2 04:08:13 my-hostname kernel: [] ? warn_slowpath_common+0x91/0xe0
Apr 2 04:08:13 my-hostname kernel: [] ? warn_slowpath_null+0x1a/0x20
Apr 2 04:08:13 my-hostname kernel: [] ? z8ce79d63e6+0x36b/0x390 [rapidrecovery_vss]
Apr 2 04:08:13 my-hostname kernel: [] ? z0cecb3b1b0+0xc9/0x160 [rapidrecovery_vss]
Apr 2 04:08:13 my-hostname kernel: [] ? z83a8f51fb7+0x50/0x110 [rapidrecovery_vss]
Apr 2 04:08:13 my-hostname kernel: [] ? autoremove_wake_function+0x0/0x40
Apr 2 04:08:13 my-hostname kernel: [] ? z83a8f51fb7+0x0/0x110 [rapidrecovery_vss]
Apr 2 04:08:13 my-hostname kernel: [] ? kthread+0x9e/0xc0
Apr 2 04:08:13 my-hostname kernel: [] ? child_rip+0xa/0x20
Apr 2 04:08:13 my-hostname kernel: [] ? kthread+0x0/0xc0
Apr 2 04:08:13 my-hostname kernel: [] ? child_rip+0x0/0x20
Apr 2 04:08:13 my-hostname kernel: ---[ end trace 864b68dac30765cb ]---