tree 19e37bd685e3a9c46805d2b86a727ea9fd59263a
parent c4f68f0b52f4d84658ee977eb7e44a80857e0b50
author Paul Durrant <paul.durrant@citrix.com> 1470042985 +0100
committer Stefano Stabellini <sstabellini@kernel.org> 1471045110 -0700

xen: handle inbound migration of VMs without ioreq server pages

VMs created on older versions on Xen will not have been provisioned with
pages to support creation of non-default ioreq servers. In this case
the ioreq server API is not supported and QEMU's only option is to fall
back to using the default ioreq server pages as it did prior to
commit 3996e85c ("Xen: Use the ioreq-server API when available").

This patch therefore changes the code in xen_common.h to stop considering
a failure of xc_hvm_create_ioreq_server() as a hard failure but simply
as an indication that the guest is too old to support the ioreq server
API. Instead a boolean is set to cause reversion to old behaviour such
that the default ioreq server is then used.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>