VM working off the file backed md(4) disk aborts with an assertion: Expression: pCritSect->u32Magic == RTCRITSECT_MAGIC

[Yuri]

I am trying to run the amd64 9.2 bootable UFS disk image as a VM in 
vbox-4.3.12 on amd64 9.2 host system.


It starts, but in a few minutes fails with an assert:

00:39:29.307864 !!Assertion Failed!!

00:39:29.307864 Expression: pCritSect->u32Magic == RTCRITSECT_MAGIC

00:39:29.307866 Location : 
/usr/ports/emulators/virtualbox-ose/work/VirtualBox-4.3.12/src/VBox/Runtime/generic/critsect-generic.cpp(197) 
int rtCritSectEnter(RTCRITSECT*, const RTLOCKVALSRCPOS*)


I am not sure if anybody ever tested virtual box this way, just 
reporting this issue here. My original purpose of doing this was testing 
out the upgrade to 10 process in a non-destructive way. But this 
apparently doesn't succeed so far.


Bootable UFS is a snapshot of the live system: mount -u -o snapshot 
/huge-disk/snapshot.img /
md0 is created with this command: mdconfig -a -t vnode -f 
/huge-disk/snapshot.img

vmdk is created with this command: VBoxManage internalcommands 
createrawvmdk -filename vm-root.vmdk -rawdisk /dev/md0

--- vmdk disk file ---

# Disk DescriptorFile
version=1
CID=5c23f5d3
parentCID=ffffffff
createType="fullDevice"

# Extent description
RW 356515855 FLAT "/dev/md0" 0

# The disk Data Base
#DDB

ddb.virtualHWVersion = "4"
ddb.adapterType="ide"
ddb.geometry.cylinders="16383"
ddb.geometry.heads="16"
ddb.geometry.sectors="63"
ddb.uuid.image="c2680566-6c07-4268-b2a5-74588f4af8c9"
ddb.uuid.parent="00000000-0000-0000-0000-000000000000"
ddb.uuid.modification="714b9817-ca57-4c8d-8e87-c757bb14b78a"
ddb.uuid.parentmodification="00000000-0000-0000-0000-000000000000"
ddb.geometry.biosCylinders="1024"
ddb.geometry.biosHeads="255"
ddb.geometry.biosSectors="63"



Yuri