Re: [Qemu-devel] [bisected] VNC server can't get all sent chars correctly

[Gerd Hoffmann]

On Sa, 2014-08-23 at 12:56 +0400, Michael Tokarev wrote:
> There's a bug filed against debian qemu package, there:
> 
>  http://bugs.debian.org/758881
> 
> which says about problems sending keypress events over VNC to
> a qemu guest, -- some keypresses gets lost, at least.

> So it looks like something else is not right here.  Before this patch,
> it wasn't possible to use keyboard with VNC client with redhat 5 guest.
> Now, it isn't possible to use keyboard with VNC in another scenario which
> worked before (so it is a regression compared with 2.0 version).

qemu 2.1 hardware emulation is more correct (ps/2 kbd queue size being
16 bytes instead of 256, matching real hardware).  That may trip up
software depending on old, broken behavior.

IMO vncdotool should be fixed to add small delays between keyboard
events, as if a real person is typing, instead of sending the key events
at the maximum possible speed.

I'm sure you can hit the issue with qemu 2.0 too, you just need longer
user input strings to trigger it, so it is less likely to happen.

cheers,
  Gerd