Virtual box USB problems

[Mumia W.]

On 09/23/2008 08:13 PM, Derek Broughton wrote:
> Mumia W. wrote:
> 
>> On 09/23/2008 12:08 PM, Derek Broughton wrote:
>>> Mr Shunz wrote:
>>>
>>>>> Specifically, your /proc/bus/usb/* needs to be writable by the
>>>>> vboxusers group - it isn't in Ubuntu, and even with the help of the
>>>>> virtualbox community I haven't been able to figure out the correct udev
>>>>> rules to make it boot that way.
>>>> this worked for me (Ubuntu 8.04):
>>>>
>>>> open /etc/init.d/mountdevsubfs.sh
>>>>
>>>> go to the section that says:
>>>>
>>>> #
>>>> # Magic to make /proc/bus/usb work
>>>> #
>>>>
>>>> uncomment the lines that follow ...
>>>>
>>>> obviusly, add yourself to vboxusers group...
>>> Yeah, that's the method I've used but it's _wrong_.  As opposed to just
>>> chmod'ing the nodes, it _will_ work at next boot, but it breaks again the
>>> next time your "initscripts" package is upgraded (because
>>> mountdevsubfs.sh is part of that package, and Ubuntu's version will
>>> overwrite it - and if you're remotely like me, you've forgotten what to
>>> do to fix the problem by the time that happens).
>>>
>>> So I've found two options that work by modifying udev - which I can set
>>> up to always work ahead of anything installed by Ubuntu - but neither of
>>> those, or my attempt at modification, is actually working :-(
>> Can't you place a command to set the desired ownership into
>> /etc/init.d/rc.local?
> 
> Well, not if the bit of the manual that NoOp quoted to the effect that you
> can't chmod a virtual filesystem is true.  I don't actually think it is...

I have no doubt that you can chmod files within a tmpfs virtual 
filesystem tree. As far as the root of the tree is concerned, chmoding 
that seems to work too--at least for tmpfs.

However, I've never tried that with usbdevfs, and never using 
virtualization.