[Redhat-s390-list] 2.4.9 hang on tasklist_lock

[Rob van der Heij <rvdheij@iae.nl>]

I found my 2.4.9-0.11 (yes, I admit - not the latest)
hung already a few times. It was spinning on the 
takslist_lock (which was holding the value 1) in my 
system with just one CPU - when I store a 0 in the 
lock it normally crashes with a program check. 
In this case fcntl.c:397 - in send_sigio_to_task

Suggestions?  Rob