Re: [Qemu-devel] USB2.0 disk format failure in windows guest

[Gerd Hoffmann]

  Hi,

> Fixing this will require qemu to copy the beginning and ending parts of
> these non-aligned qTDs into separate bounce buffers so that the URB
> length can be divisible by 512.

Worth trying:  http://www.kraxel.org/cgit/qemu/log/?h=usb.80

It puts the qemu usb passthrough code upside down.  All xfers will go
through a bounce buffer, requests are submitted via libusbx.  That
should fix it.  Of course there is the risk of regressions in other
areas as it is all new code.  Also make sure you have libusbx-devel
installed, otherwise qemu will fallback to the old code which uses usbfs
ioctls directly.

cheers,
  Gerd