kern/121809: unable to umount

[barbara]

>Number:         121809
>Category:       kern
>Synopsis:       unable to umount
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Mar 17 23:50:00 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     barbara
>Release:        7.0-STABLE
>Organization:
>Environment:
FreeBSD satanasso.local.net 7.0-STABLE FreeBSD 7.0-STABLE #0: Mon Mar 17 11:19:37 CET 2008     root at satanasso.local.net:/usr/obj/usr/src/sys/SATANASSO  i386
>Description:
I've rebuild world+kernel this morning.
After installworld and mergemaster, I mounted another UFS2 partition (a 6.3 install in the same disk) and removed a file, but after that I was unable to umount it and I was forced do run fsck on the partition.
Tried again after reboot with the same result.
If I just mount then umount or create a file before unmounting all seems ok, but if I delete a file on the mounted partition, the device is reported as busy.
fstat doesn't report anything on the involved mountpoints.
I have these messages appear on  /var/log/messages

handle_workitem_remove: vget: got error 16 while accessing filesystem
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
softdep_waitidle: Failed to flush worklist for 0xc58f6d0c
handle_workitem_remove: vget: got error 16 while accessing filesystem
softdep_waitidle: Failed to flush worklist for 0xc58f529c
softdep_waitidle: Failed to flush worklist for 0xc58f529c

>How-To-Repeat:

>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: