Make sure that the worker thread knows the type early enough to grab Giant for vnode backing.
Make sure that the worker thread knows the type early enough to
grab Giant for vnode backing.

Found by:	pho & tegge

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase