[PATCH 5/6] KVM: Documentation: Add the missing mmu_valid_gen into kvm_mmu_page

Mingwei Zhang
2023-06-18T00:09:35Z

Add mmu_valid_gen into kvm_mmu_page description. mmu_valid_gen is used in
shadow MMU for fast zapping. Update the doc to reflect that.

Signed-off-by: Mingwei Zhang <mizhang@google.com>
---
Documentation/virt/kvm/x86/mmu.rst | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/Documentation/virt/kvm/x86/mmu.rst b/Documentation/virt/kvm/x86/mmu.rst
index 3dce2426ad6d..0dbdb7fb8cc6 100644
--- a/Documentation/virt/kvm/x86/mmu.rst
+++ b/Documentation/virt/kvm/x86/mmu.rst
@@ -208,6 +208,10 @@ Shadow pages contain the following information:
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
CR4.LA57=1) and is shadowing L1's 4-level NPT (L1 CR4.LA57=1).
+ mmu_valid_gen:
+ Used by comparing against kvm->arch.mmu_valid_gen to check whether the
+ shadow page is obsolete thus a convenient variable for fast zapping.
+ Note that TDP MMU does not use mmu_valid_gen.
gfn:
Either the guest page table containing the translations shadowed by this
page, or the base page frame for linear translations. See role.direct.
--
2.41.0.162.gfafddb0af9-goog