port-sparc/45316: Raster console locks up executing top on a SparcStation 2

[Georg.Brein%unibas.ch@localhost]

>Number:         45316
>Category:       port-sparc
>Synopsis:       Raster console locks up executing top 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 15:50:00 +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

>Description:
Starting top on the console frame buffer locks up the console (both on a CG3 
and a CG6); I'm using the generic kernel with option RASTERCONSOLE 
(screen-#columns = 80, screen-#rows = 34, i. e. the default value; TERM=sun). 
Killing top (from a serial terminal) doesn't free the console (but Stop-A to 
the debugger still works).

With a custom kernel without option RASTERCONSOLE top works slowly but 
flawlessly (at least at screensize 80x34).
>How-To-Repeat:
Boot the generic kernel on a SparcStation 2, log in and start top.
>Fix: