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

[Michael Tokarev <mjt@tls.msk.ru>]

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.

The bisection between qemu 2.0 and 2.1 leads to this commit:

commit 2858ab09e6f708e381fc1a1cc87e747a690c4884
Author: Gonglei <arei.gonglei@huawei.com>
Date:   Thu Apr 24 20:06:19 2014 +0800

    ps2: set ps/2 output buffer size as the same as kernel

    According to the PS/2 Mouse/Keyboard Protocol, the keyboard outupt buffer size
    is 16 bytes. And the PS2_QUEUE_SIZE 256 was introduced in Qemu from the very
    beginning.

    When I started a  redhat5.6 32bit guest, meanwhile tapped the keyboard as quickly as
    possible, the screen would show me "i8042.c: No controller found". As a result,
    I couldn't use the keyboard in the VNC client.

    Previous discussion about the issue in maillist:
    http://thread.gmane.org/gmane.comp.emulators.qemu/43294/focus=47180

    This patch has been tested on redhat5.6 32-bit/suse11sp3 64-bit guests.
    More easy meathod to reproduce:
    1.boot a guest with libvirt.
    2.connect to VNC client.
    3.as you see the BIOS, bootloader, Linux booting, run the follow simply shell script:
    for((i=0;i<10000000;i++)) do virsh send-key redhat5.6 KEY_A; done

    Actual results:
    dmesg show "i8042.c: No controller found." And the keyboard is out of work.

    Signed-off-by: Gonglei <arei.gonglei@huawei.com>
    Reviewed-by: Juan Quintela <quintela@redhat.com>
    Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>


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).

What do we do with this? :)

Thanks,

/mjt