Commit 4a2bc01b authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: LoongArch: Mark "struct page" pfns accessed only in "slow" page fault path 



Mark pages accessed only in the slow path, before dropping mmu_lock when
faulting in guest memory so that LoongArch can convert to
kvm_release_faultin_page() without tripping its lockdep assertion on
mmu_lock being held.

Reviewed-by: default avatarBibo Mao <maobibo@loongson.cn>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Tested-by: default avatarDmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-ID: <20241010182427.1434605-67-seanjc@google.com>
parent 0fe133a3

arch/loongarch/kvm/mmu.c

+2 −18
Original line number Diff line number Diff line
@@ -552,12 +552,10 @@ bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 
static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool write)

{

	int ret = 0;

	kvm_pfn_t pfn = 0;

	kvm_pte_t *ptep, changed, new;

	gfn_t gfn = gpa >> PAGE_SHIFT;

	struct kvm *kvm = vcpu->kvm;

	struct kvm_memory_slot *slot;

	struct page *page;



	spin_lock(&kvm->mmu_lock);
@@ -570,8 +568,6 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ 


	/* Track access to pages marked old */

	new = kvm_pte_mkyoung(*ptep);

	/* call kvm_set_pfn_accessed() after unlock */



	if (write && !kvm_pte_dirty(new)) {

		if (!kvm_pte_write(new)) {

			ret = -EFAULT;
@@ -595,22 +591,10 @@ static int kvm_map_page_fast(struct kvm_vcpu *vcpu, unsigned long gpa, bool writ 
	}



	changed = new ^ (*ptep);

	if (changed) {

	if (changed)

		kvm_set_pte(ptep, new);

		pfn = kvm_pte_pfn(new);

		page = kvm_pfn_to_refcounted_page(pfn);

		if (page)

			get_page(page);

	}

	spin_unlock(&kvm->mmu_lock);



	if (changed) {

		if (kvm_pte_young(changed))

			kvm_set_pfn_accessed(pfn);



		if (page)

			put_page(page);

	}

	spin_unlock(&kvm->mmu_lock);



	if (kvm_pte_dirty(changed))

		mark_page_dirty(kvm, gfn);