Re:Re: USB4BSD release candidate number 3 - request for review

It's a bug? 
/boot/loader.conf:
zfs_load="YES"
vm.kmem_size_max="2048M"
vm.kmem_size="2048M"
vfs.zfs.zil_disable=1
vfs.zfs.prefetch_disable=1
hw.psm.synaptics_support=1
legal.intel_iwn.license_ack=1
acpi_ibm_load="YES"
snd_hda_load="YES"
powerd_enable="YES"
linux_load="YES"
if_iwn_load="YES"
ubtbcmfw_load="YES"
usb2_bluetooth_load="YES"
usb2_bluetooth_ng_load="YES"
usb2_bluetooth_fw_load="YES"
usb2_controller_uhci_load="YES"
usb2_controller_ehci_load="YES"
usb2_input_ms_load="YES"
usb2_storage_mass_load="YES"
usb2_image_load="YES" 

kldstat:
Id Refs Address            Size     Name
 1   82 0xffffffff80100000 756b28   kernel (/boot/kernel/kernel)
 2    1 0xffffffff80857000 3a88f8   zfs.ko (/boot/kernel/zfs.ko)
 3    2 0xffffffff80c00000 6670     opensolaris.ko (/boot/kernel/opensolaris.ko)
 4    2 0xffffffff80c07000 a1dd8    linux.ko (/boot/kernel/linux.ko)
 5    1 0xffffffff80ca9000 28470    snd_hda.ko (/boot/kernel/snd_hda.ko)
 6    2 0xffffffff80cd2000 bc4d0    sound.ko (/boot/kernel/sound.ko)
 7    1 0xffffffff80d8f000 7a38     acpi_ibm.ko (/boot/kernel/acpi_ibm.ko)
 8    1 0xffffffff80d97000 24e80    if_iwn.ko (/boot/kernel/if_iwn.ko)
 9    1 0xffffffff80dbc000 6c18     ubtbcmfw.ko (/boot/kernel/ubtbcmfw.ko)
10    2 0xffffffff80dc3000 27f88    usb.ko (/boot/kernel/usb.ko)
11    3 0xffffffff80deb000 be8      usb2_bluetooth.ko (/boot/kernel/usb2_bluetooth.ko)
12   12 0xffffffff80dec000 9c868    usb2_core.ko (/boot/kernel/usb2_core.ko)
13    1 0xffffffff80e89000 bbf8     usb2_bluetooth_ng.ko (/boot/kernel/usb2_bluetooth_ng.ko)
14    6 0xffffffff80e95000 1ad00    netgraph.ko (/boot/kernel/netgraph.ko)
15    1 0xffffffff80eb0000 a950     usb2_bluetooth_fw.ko (/boot/kernel/usb2_bluetooth_fw.ko)
16    1 0xffffffff80ebb000 15978    usb2_controller_uhci.ko (/boot/kernel/usb2_controller_uhci.ko)
17    3 0xffffffff80ed1000 8780     usb2_controller.ko (/boot/kernel/usb2_controller.ko)
18    1 0xffffffff80eda000 19dd0    usb2_controller_ehci.ko (/boot/kernel/usb2_controller_ehci.ko)
19    1 0xffffffff80ef4000 e128     usb2_input_ms.ko (/boot/kernel/usb2_input_ms.ko)
20    2 0xffffffff80f03000 bd0      usb2_input.ko (/boot/kernel/usb2_input.ko)
21    1 0xffffffff80f04000 15c28    usb2_storage_mass.ko (/boot/kernel/usb2_storage_mass.ko)
22    2 0xffffffff80f1a000 bd8      usb2_storage.ko (/boot/kernel/usb2_storage.ko)
23    1 0xffffffff80f1b000 bd0      usb2_image.ko (/boot/kernel/usb2_image.ko)
24    4 0xffffffff81022000 1835     ng_bluetooth.ko (/boot/kernel/ng_bluetooth.ko)
25    1 0xffffffff81024000 133a9    ng_hci.ko (/boot/kernel/ng_hci.ko)
26    1 0xffffffff81038000 174b7    ng_l2cap.ko (/boot/kernel/ng_l2cap.ko)
27    1 0xffffffff81050000 2de0a    ng_btsocket.ko (/boot/kernel/ng_btsocket.ko)
28    1 0xffffffff8107e000 535e     ng_socket.ko (/boot/kernel/ng_socket.ko)
29    1 0xffffffff81084000 8059     vkbd.ko (/boot/kernel/vkbd.ko)
30    1 0xffffffff8108d000 6f4      rtc.ko (/usr/local/modules/rtc.ko)

I build kernel without usb*.I notice usb.ko's refs is 2, after i run kldunload usb.ko, it is 1.when i try to kldunload usb.ko another time,it return "Device busy".Any thing still request usb.ko? 



Thanks,
kevin