Re: [Qemu-devel] [vfio-users] [PATCH v2 1/3] input: add qemu_input_qcode_to_linux + qemu_input_linux_to_qcode

[Gerd Hoffmann <kraxel@redhat.com>]

On Mo, 2016-01-18 at 11:47 +0000, Jonathan Scruggs wrote:
> Hi Gerd,
> 
> Would there be a way to add repeating keys back in that doesn't cause
> issues? Maybe slow down the repeat cycle? Or is this strictly a issue
> with how the actual event drivers or the buffers work and would need
> changing to that on the host side?

I don't know ...

> In my mind it seams fairly straightforward in just forwarding these
> events to the VM.

I assumed that as well, it was there initially and only removed after it
turned out to cause problems.

I've added a patch to the git branch bringing it back, but guarded with
a new config option (repeat={on,off}) and turned off by default.

> Would it be different if the keyboard was using the PS/2 versus the
> USB interface on the guest? I have a USB controller added for the
> guest but the keyboard and mouse are on PS/2 interfaces.

Worth testing.  Just add "-device usb-kbd" to the qemu command line and
see what happens ...

> A second thought. What if you made the keyboard and mouse USB only,
> then on the guest, make sure the USB controller is using Message
> Signal-Based interrupts. On Windows, the controller was set to the old
> style Line-Based. The slow downs could be caused by a lake in speed
> with he interrupts and USB polling speed.

In case windows is new enough to have xhci support (win8+) you can try
using a xhci hostadapter, which supports MSI (uhci and ehci don't), then
hook up the usb keyboard to it.

"-device nec-usb-xhci,id=xhci -device usb-kbd,bus=xhci.0"

cheers,
  Gerd