[virt-tools-list] Problem accessing USB devices under a VM running Windows 10

[Jeffery Small]

On Tue, Feb 07, 2017 at  16:54:34, Christophe Fergeau wrote:

>On Mon, Feb 06, 2017 at 11:19:08AM -0800, Jeffery Small wrote:
>> 
>> I'm on an Xubuntu 16.10 system running the latest version of QEMU-KVM
>> (1.2.6.1).  I have a VM running Windows 10, which is launched from
>> virt-manager.
>> 
>> Question #1:
>> 
>> With the OS not running, from the Hardware Details page I have used "Add
>> Hardware" to attach a USB flash drive.  In the hardware list it shows
>> up as "USB 058f:6387" and the details show "Device: 002:003 Alcor Micro
>> Corp. Flash Drive".
>> 
>> Nevertheless, when I launch the Windows 10 OS, File Explorer does not see
>> this device.  I've also looked in Device Manager and can see no reference
>> to the flash drive.
>> 
>> Any clue as to the nature of the problem and what must be done to make this
>> visible to the Windows OS?  I am doing this with a flash drive as a test in
>> order to get device attachment working.  Ultimately, I will be attaching a
>> usb dongle key to the port which must be seen by a program running in this
>> environment.
>
>And this device has a partition table, and a file system Windows knows
>about ? Last time I used Windows, I could find a place showing the
>various partitions on the device, did you check there?

The thumb drive is a 4GB Flash drive with a FAT32 filesystem.  It can be
plugged into any other Windows computer, automounts, displays in File
Explorer and can be written to without problem.  When plugged into the
Ubuntu system it displays and can be mounted.  I make sure it is unmounted
in Linux and when I start the VM I see the device registered in the
virt-viewer hardware details page, but there is no sign of the device
within Windows itself.  It doesn't automount, it doesn't show up in the
Devices and Printers tool.  I ran the Computer Management tool and looked
under the Device Manager section, but see no signs of the thumb drive.
Using the Disk Devices tool, there is a listing for the "QEMU HARDDISK ATA
Device", but nothing for and attached USB drive.

So I am still at a loss regarding what to investigate next.  Any additional
suggestions?  Others must be getting this to work!