port-sparc/45314: Spurious mouse button events under X11 on a SparcStation 2

[Georg.Brein%unibas.ch@localhost]

>Number:         45314
>Category:       port-sparc
>Synopsis:       Spurious mouse button events under X11 on a SparcStation 2
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-sparc-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Aug 30 15:20:00 +0000 2011
>Originator:     Georg Brein
>Release:        NetBSD 5.1 sparc
>Organization:
University of Basel/Switzerland
>Environment:
NetBSD se-zulu.psycho.unibas.ch 5.1 NetBSD 5.1 (GENERIC) #0: Sat Nov  6 
18:44:40 UTC 2010  
builds%b6.netbsd.org@localhost:/home/builds/ab/netbsd-5-1-RELEASE/sparc/201011061943Z-obj/home/builds/ab/netbsd-5-1-RELEASE/src/sys/arch/sparc/compile/GENERIC
 sparc

SparcStation 2, firmware rev. 2.9
>Description:
Quickly moving the mouse in wide cycles under X11 (without actually pressing 
one of the mouse buttons) seems to generate spurious mouse button events; this 
is quite annoying because it sometimes leads to unwanted copy-and-pasting 
(which is especially annoying with xterm windows, even more so if you are 
logged in as root...). The spurious mouse button events seem to happen more 
often if the mouse cursor crosses window borders during the movement (causing 
twm to redraw the window border).

I experienced the problem both with a type 4 optical mouse attached to a type 4 
keyboard and a type 5 mechanical mouse attached to a type 5 keyboard. There are 
no such problems with the same hardware under Solaris 2.5.1.

My (uninformed) guess is that the SparcStation 2 (at least under NetBSD) is not 
fast enough to cope with the data from the mouse (I'm using a CG3 frame buffer).
>How-To-Repeat:
Boot a generic kernel on a SparcStation 2, activate xdm, log in, open a few 
xterm windows and type "ls /dev" in all of them (this is just to fill the xterm 
screens with harmless text). Then start to move the mouse quickly in wide 
circles on the screen (crossing window borders) without pressing a mouse button 
and watch the spurious copy-and-pasting (inside the xterm windows) or the twm 
menus flashing briefly (on the root window). 
>Fix:
Move your mouse more gently :-)