Synchronizing SCSI cache: 
scsi_debug: slave_detach <0 0 0 0>
Badness in put_bus at drivers/base/bus.c:277
Call Trace:
 [<c01b2ed9>] put_bus+0x69/0x80
 [<c01b1ef3>] device_del+0x33/0x80
 [<c01f740b>] scsi_host_chk_and_release+0xdb/0x220
 [<c01a67e0>] __copy_to_user+0x30/0x50
 [<c01339dc>] buffered_rmqueue+0xac/0x120
 [<e085afe0>] driver_template+0x0/0x6c [scsi_debug]
 [<c01f7330>] scsi_host_chk_and_release+0x0/0x220
 [<c01f72be>] scsi_tp_for_each_host+0x3e/0x40
 [<e085afe0>] driver_template+0x0/0x6c [scsi_debug]
 [<c01f7d55>] scsi_unregister_host+0x25/0x70
 [<e085afe0>] driver_template+0x0/0x6c [scsi_debug]
 [<c01f7330>] scsi_host_chk_and_release+0x0/0x220
 [<e085972f>] exit_this_scsi_driver+0xf/0x20 [scsi_debug]
 [<e085afe0>] driver_template+0x0/0x6c [scsi_debug]
 [<c011910c>] free_module+0xac/0xc0
 [<c01184c3>] sys_delete_module+0x93/0x1b0
 [<c01073e3>] syscall_call+0x7/0xb

scsi_debug: [last] release
scsi : 0 hosts left.