Or Qemu, for having its keyboard buffer too large (I'm not sure, but probably
256 bytes)?
All references (*) i could find mention 16 bytes of output buffer
(including the Linux source as you mentioned, which was reduced from 32
to 16 somewhere in the 2.6.10 era).
http://www.computer-engineering.org/ps2protocol/
http://linux.bkbits.net:8080/linux-2.6.28-stable/drivers/input/serio/i8042.h?PAGE=diffs&REV=4203735dp_doSExYU6ido8KnczbjzQ
Reducing PS2_QUEUE_SIZE to 16 also makes the Linux detection loop happy.
If QEMU claims to emulate i8042, it should be similar to real hardware.
However i'm not familiar with PS/2 or i8042. Anthony?