vio.c:__vio_register_driver && LPAR Migration issue

[Michael Bringmann]

Hello:
    I have been observing an anomaly during LPAR migrations between
a couple of P8 systems.

This is the problem.  After migrating an LPAR, the PPC mobility code
receives RTAS requests to delete nodes with platform-/hardware-specific
attributes when restarting the kernel after a migration.  My example is
for migration between a P8 Alpine and a P8 Brazos.  Among the nodes
that I see being deleted are 'ibm,random-v1', 'ibm,compression-v1',
'ibm,platform-facilities', and 'ibm,sym-encryption-v1'.  Of these
nodes, the following are created during initial boot by calls to
vio_register_driver:

drivers/char/hw_random/pseries-rng.c
        ibm,random-v1

drivers/crypto/nx/nx-842-pseries.c
        ibm,compression-v1

drivers/crypto/nx/nx.c
        ibm,sym-encryption-v1

After the migration, these nodes are deleted, but nothing recreates
them.  If I boot the LPAR on the target system, the nodes are added
again.

My question is how do we recreate these nodes after migration?

Thanks.

-- 
Michael W. Bringmann
Linux Technology Center
IBM Corporation
Tie-Line  363-5196
External: (512) 286-5196
Cell:       (512) 466-0650
mwb at linux.vnet.ibm.com