Commit 9e3fbdfd authored by Lai Jiangshan's avatar Lai Jiangshan Committed by Sean Christopherson
Browse files

kvm: x86/mmu: Don't clear write flooding for direct SP 



Although there is no harm, but there is no point to clear write
flooding for direct SP.

Signed-off-by: default avatarLai Jiangshan <jiangshan.ljs@antgroup.com>
Link: https://lore.kernel.org/r/20230105100310.6700-1-jiangshanlai@gmail.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent dc1ae59f

arch/x86/kvm/mmu/paging_tmpl.h

+3 −5
Original line number Diff line number Diff line
@@ -642,12 +642,12 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, 
	if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root.hpa)))

		goto out_gpte_changed;



	for (shadow_walk_init(&it, vcpu, fault->addr);

	     shadow_walk_okay(&it) && it.level > gw->level;

	     shadow_walk_next(&it)) {

	for_each_shadow_entry(vcpu, fault->addr, it) {

		gfn_t table_gfn;



		clear_sp_write_flooding_count(it.sptep);

		if (it.level == gw->level)

			break;



		table_gfn = gw->table_gfn[it.level - 2];

		access = gw->pt_access[it.level - 2];
@@ -692,8 +692,6 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, 
	trace_kvm_mmu_spte_requested(fault);



	for (; shadow_walk_okay(&it); shadow_walk_next(&it)) {

		clear_sp_write_flooding_count(it.sptep);



		/*

		 * We cannot overwrite existing page tables with an NX

		 * large page, as the leaf could be executable.