kern/37925: more locking problems with unionfs

[christos%netbsd.org@localhost]

>Number:         37925
>Category:       kern
>Synopsis:       more locking problems with unionfs
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jan 30 16:35:00 +0000 2008
>Originator:     Christos Zoulas
>Release:        NetBSD 4.99.1
>Organization:
        none but trying.
>Environment:
System: NetBSD t61.localnet 4.99.50 NetBSD 4.99.50 (GENERIC) #0: Sat Jan 26 
20:01:43 EST 2008  
ljt%t61.localnet@localhost:/p/src/sys/arch/amd64/compile/GENERIC amd64
Architecture: amd64
Machine: amd64
>Description:
        instant locking panic.
        http://www.zoulas.com/images/NetBSD/imgp0253.jpg

>How-To-Repeat:
        mkdir /a /b
        mount -t union /a /b
        touch /b/c

>Fix:
        ?