Add the missing description for guest_mode in kvm_mmu_page_role
description.  guest_mode tells KVM whether a shadow page is used for the L1
or an L2. Update the missing field in documentation.

Signed-off-by: Mingwei Zhang <mizhang@google.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
---
 Documentation/virt/kvm/x86/mmu.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/virt/kvm/x86/mmu.rst b/Documentation/virt/kvm/x86/mmu.rst
index 8364afa228ec..561efa8ec7d7 100644
--- a/Documentation/virt/kvm/x86/mmu.rst
+++ b/Documentation/virt/kvm/x86/mmu.rst
@@ -202,6 +202,8 @@ Shadow pages contain the following information:
     Is 1 if the MMU instance cannot use A/D bits.  EPT did not have A/D
     bits before Haswell; shadow EPT page tables also cannot use A/D bits
     if the L1 hypervisor does not enable them.
+  role.guest_mode:
+    Indicates the shadow page is created for a nested guest.
   role.passthrough:
     The page is not backed by a guest page table, but its first entry
     points to one.  This is set if NPT uses 5-level page tables (host
-- 
2.41.0.585.gd2178a4bd4-goog