- /sys/bus/usb/drivers with VirtualBox 3 (pic by mirmurr.blogspot.com)
Ever since VirtualBox 3 came out, we’ve had random reports of mobile broadband cards not working with NetworkManager 0.7.x. Here’s why: VirtualBox 3 thinks it’s hilarious to screw around with sysfs. You don’t even have to run it, you just have to install it.
/sys/bus/usb/drivers without VirtualBox:
[dcbw@localhost ~]$ ls -al /sys/bus/usb/drivers total 0 drwxr-xr-x. 15 root root 0 2009-10-14 14:33 . drwxr-xr-x. 4 root root 0 2009-10-14 14:31 .. drwxr-xr-x. 2 root root 0 2009-10-14 15:40 btusb drwxr-xr-x. 2 root root 0 2009-10-14 14:33 cdc_acm drwxr-xr-x. 2 root root 0 2009-10-14 14:33 cdc_ether drwxr-xr-x. 2 root root 0 2009-10-14 14:33 cdc_wdm drwxr-xr-x. 2 root root 0 2009-10-14 15:40 hiddev drwxr-xr-x. 2 root root 0 2009-10-14 15:40 hub drwxr-xr-x. 2 root root 0 2009-10-14 15:40 qcserial drwxr-xr-x. 2 root root 0 2009-10-14 14:33 usb drwxr-xr-x. 2 root root 0 2009-10-14 15:40 usbfs drwxr-xr-x. 2 root root 0 2009-10-14 15:40 usbhid drwxr-xr-x. 2 root root 0 2009-10-14 15:40 usbserial drwxr-xr-x. 2 root root 0 2009-10-14 15:40 usbserial_generic drwxr-xr-x. 2 root root 0 2009-10-14 15:40 uvcvideo
/sys/bus/usb/drivers with VirtualBox 3:
[dcbw@localhost ~]$ ls -al /sys/bus/usb/drivers total 0 drwxr-xr-x. 10 root root 0 2009-10-14 00:03 . drwxr-xr-x. 4 root root 0 2009-10-14 00:04 .. dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 001 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 002 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 003 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 004 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 005 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 006 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 007 dr-xr-xr-x. 2 root root 0 2009-10-14 00:03 008 -r--r--r--. 1 root root 0 2009-10-14 01:44 devices
That’s obviously wrong. And your sysfs USB device links still point to their driver in /sys/bus/usb/drivers and thus are completely broken:
[dcbw@localhost ~]$ ls -al /sys/devices/pci0000:00/0000:00:1a.0/usb3/3-2/3-2:1.0/driver lrwxrwxrwx. 1 root root 0 2009-10-14 02:20 /sys/devices/pci0000:00/0000:00:1a.0/usb3/3-2/3-2:1.0/driver -> ../../../../../../bus/usb/drivers/option
FAIL
Then HAL can’t determine the device’s driver because VirtualBox busted the link, and thus the modem will fail to be recognized by NetworkManager. No 3G for you! You can work around this with a HAL .fdi file:
<?xml version="1.0" encoding="UTF-8"?> <!-- -*- xml -*- -->
<deviceinfo version="0.2">
<device>
<match key="info.subsystem" string="usb">
<match key="usb.vendor_id" int="0x0af0">
<match key="usb.product_id" int_outof="0x6701">
<merge key="info.linux.driver" type="string">option</merge>
</match>
</match>
</match>
</device>
</deviceinfo>
Drop that (after fixing the USB IDs and driver for your device) into /usr/share/hal/fdi/information/20thirdparty/10-vbox-usb-fixup.patch and replug your modem. Or uninstall VirtualBox. Or revert to VirtualBox 2. Or update to NetworkManager 0.8.x snapshots.
You have been served.
VirtualBox devs, any chance you can stop messing with sysfs? I can file a bug if you like…
Ewww. That sounds like they are mounting usbfs over /sys/bus/usb/devices. If programs use usbfs at all, wouldn’t they expect to find it in /proc/bus/usb?
If that’s the case, does unmounting usbfs make a difference?
Hmm, interesting. I’ll have to check that out, thanks! Could just be an installer mistake, but if something in VB depends on it being there that’s a bug I could file I guess. Sucks that it breaks HAL though.
The only apps I’ve seen that needed usbfs were ones compiled against old versions of libusb (new versions make do with the /dev/bus/usb tree maintained by udev).
If VirtualBox really does depend on usbfs being mounted there under /sys, that is particularly brain dead: you’d never end up with that configuration even by copying what other people do.