kern/43589: Rump mount process panics with assertion on file images

[Matthew Mondor <mm_lists%pulsar-zone.net@localhost>]

>Number:         43589
>Category:       kern
>Synopsis:       Rump mount process panics with assertion on file images
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Jul 09 18:15:00 +0000 2010
>Originator:     Matthew Mondor
>Release:        NetBSD 5.1_RC3
>Organization:
>Environment:
System: NetBSD behemoth.xisop 5.1_RC3 NetBSD 5.1_RC3 (GENERIC_MM) #0: Fri Jul 9 
02:43:35 EDT 2010 
root%behemoth.xisop@localhost:/usr/obj/sys/arch/i386/compile/GENERIC_MM i386
Architecture: i386
Machine: i386
>Description:

When using rump to mount a file image directly (as opposed to a block
device), an assertion occurs followed by a panic.  Note that of course
only the process panics, not the host kernel.
This apparently works on -current so I suppose that a pullup to
netbsd-5 would be nice :)

behemoth$ rump_cd9660 -o ro,nodev,nosuid ./image.iso ~/cdrom/
rump_cd9660: "./image.iso" is a non-resolved or relative path.
rump_cd9660: using "/tmp/image.iso" instead.
rump_cd9660: "/home/mmondor/cdrom/" is a non-resolved or relative path.
rump_cd9660: using "/home/mmondor/cdrom" instead.
sysctl_createv: sysctl_locate(disknames) returned 2
sysctl_createv: sysctl_locate(iostatnames) returned 2
sysctl_createv: sysctl_locate(iostats) returned 2
panic: kernel diagnostic assertion "cnp->cn_namelen != 0 && cnp->cn_pnbuf[0] != 
'.'" failed: file "/usr/src/lib/librump/../../sys/rump/librump/rumpkern/vfs.c", 
line 201
[1]   Abort trap              rump_cd9660 -o ro,nodev,nosuid ./image.iso 
~/cdrom/
behemoth$ 

>How-To-Repeat:
Try to mount an image file directly with rump on netbsd-5.
>Fix:
Unknown