[PATCH 09/24] kvm: x86/mmu: Don't redundantly clear TDP MMU pt memory

Ben Gardon
2021-01-12T18:12:18Z

The KVM MMU caches already guarantee that shadow page table memory will
be zeroed, so there is no reason to re-zero the page in the TDP MMU page
fault handler.

No functional change intended.

Reviewed-by: Peter Feiner <pfeiner@google.com>

Signed-off-by: Ben Gardon <bgardon@google.com>
---
arch/x86/kvm/mmu/tdp_mmu.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 411938e97a00..55df596696c7 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -665,7 +665,6 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
sp = alloc_tdp_mmu_page(vcpu, iter.gfn, iter.level);
list_add(&sp->link, &vcpu->kvm->arch.tdp_mmu_pages);
child_pt = sp->spt;
- clear_page(child_pt);
new_spte = make_nonleaf_spte(child_pt,
!shadow_accessed_mask);

--
2.30.0.284.gd98b1dd5eaa7-goog