Curretly, the memory region of backed memory is all directly
mapped to guest's address space, however, it will be not true
for nvdimm device if we introduce nvdimm label which only can
be indirectly accessed by ACPI DSM method
Also it improves the comments a bit to reflect this fact
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
3c3e88a814