KVM: x86: document special identity map address value

Setting it to 0 leads to setting it to the default value, let's document
this.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index e63a35fafef0e153c30023e92622111006d1dd7c..22bc5a052a5d69995dbfb84c571a7b5b7a58284a 100644 (file)
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1124,6 +1124,9 @@ guest physical address space and must not conflict with any memory slot
 or any mmio address.  The guest may malfunction if it accesses this memory
 region.
 
+Setting the address to 0 will result in resetting the address to its default
+(0xfffbc000).
+
 This ioctl is required on Intel-based hosts.  This is needed on Intel hardware
 because of a quirk in the virtualization implementation (see the internals
 documentation when it pops into existence).