tree 293b915125a0ee9731dfc896ff394fd291a33c8a
parent 3053c762444a83ec6a8777f9476668b23b8ab180
author Olaf Hering <olaf@aepfle.de> 1450137702 -0800
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1450149305 -0800

Drivers: hv: vss: run only on supported host versions

The Backup integration service on WS2012 has appearently trouble to
negotiate with a guest which does not support the provided util version.
Currently the VSS driver supports only version 5/0. A WS2012 offers only
version 1/x and 3/x, and vmbus_prep_negotiate_resp correctly returns an
empty icframe_vercnt/icmsg_vercnt. But the host ignores that and
continues to send ICMSGTYPE_NEGOTIATE messages. The result are weird
errors during boot and general misbehaviour.

Check the Windows version to work around the host bug, skip hv_vss_init
on WS2012 and older.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>