Commit 7250533a authored by Will Deacon's avatar Will Deacon Committed by Marc Zyngier
Browse files

KVM: arm64: Ignore MMU notifier callbacks for protected VMs 



In preparation for supporting the donation of pinned pages to protected
VMs, return early from the MMU notifiers when called for a protected VM,
as the necessary hypercalls are exposed only for non-protected guests.

Reviewed-by: default avatarFuad Tabba <tabba@google.com>
Tested-by: default avatarFuad Tabba <tabba@google.com>
Tested-by: default avatarMostafa Saleh <smostafa@google.com>
Signed-off-by: default avatarWill Deacon <will@kernel.org>
Link: https://patch.msgid.link/20260330144841.26181-9-will@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 733774b5

arch/arm64/kvm/mmu.c

+6 −3
Original line number Diff line number Diff line
@@ -340,6 +340,9 @@ static void __unmap_stage2_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 
void kvm_stage2_unmap_range(struct kvm_s2_mmu *mmu, phys_addr_t start,

			    u64 size, bool may_block)

{

	if (kvm_vm_is_protected(kvm_s2_mmu_to_kvm(mmu)))

		return;



	__unmap_stage2_range(mmu, start, size, may_block);

}
@@ -2223,7 +2226,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu) 


bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)

{

	if (!kvm->arch.mmu.pgt)

	if (!kvm->arch.mmu.pgt || kvm_vm_is_protected(kvm))

		return false;



	__unmap_stage2_range(&kvm->arch.mmu, range->start << PAGE_SHIFT,
@@ -2238,7 +2241,7 @@ bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 
{

	u64 size = (range->end - range->start) << PAGE_SHIFT;



	if (!kvm->arch.mmu.pgt)

	if (!kvm->arch.mmu.pgt || kvm_vm_is_protected(kvm))

		return false;



	return KVM_PGT_FN(kvm_pgtable_stage2_test_clear_young)(kvm->arch.mmu.pgt,
@@ -2254,7 +2257,7 @@ bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) 
{

	u64 size = (range->end - range->start) << PAGE_SHIFT;



	if (!kvm->arch.mmu.pgt)

	if (!kvm->arch.mmu.pgt || kvm_vm_is_protected(kvm))

		return false;



	return KVM_PGT_FN(kvm_pgtable_stage2_test_clear_young)(kvm->arch.mmu.pgt,

arch/arm64/kvm/pkvm.c

+18 −1
Original line number Diff line number Diff line
@@ -407,7 +407,12 @@ int pkvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, 


int pkvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size)

{

	lockdep_assert_held_write(&kvm_s2_mmu_to_kvm(pgt->mmu)->mmu_lock);

	struct kvm *kvm = kvm_s2_mmu_to_kvm(pgt->mmu);



	if (WARN_ON(kvm_vm_is_protected(kvm)))

		return -EPERM;



	lockdep_assert_held_write(&kvm->mmu_lock);



	return __pkvm_pgtable_stage2_unshare(pgt, addr, addr + size);

}
@@ -419,6 +424,9 @@ int pkvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size) 
	struct pkvm_mapping *mapping;

	int ret = 0;



	if (WARN_ON(kvm_vm_is_protected(kvm)))

		return -EPERM;



	lockdep_assert_held(&kvm->mmu_lock);

	for_each_mapping_in_range_safe(pgt, addr, addr + size, mapping) {

		ret = kvm_call_hyp_nvhe(__pkvm_host_wrprotect_guest, handle, mapping->gfn,
@@ -450,6 +458,9 @@ bool pkvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, u64 
	struct pkvm_mapping *mapping;

	bool young = false;



	if (WARN_ON(kvm_vm_is_protected(kvm)))

		return false;



	lockdep_assert_held(&kvm->mmu_lock);

	for_each_mapping_in_range_safe(pgt, addr, addr + size, mapping)

		young |= kvm_call_hyp_nvhe(__pkvm_host_test_clear_young_guest, handle, mapping->gfn,
@@ -461,12 +472,18 @@ bool pkvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, u64 
int pkvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot,

				    enum kvm_pgtable_walk_flags flags)

{

	if (WARN_ON(kvm_vm_is_protected(kvm_s2_mmu_to_kvm(pgt->mmu))))

		return -EPERM;



	return kvm_call_hyp_nvhe(__pkvm_host_relax_perms_guest, addr >> PAGE_SHIFT, prot);

}



void pkvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr,

				 enum kvm_pgtable_walk_flags flags)

{

	if (WARN_ON(kvm_vm_is_protected(kvm_s2_mmu_to_kvm(pgt->mmu))))

		return;



	WARN_ON(kvm_call_hyp_nvhe(__pkvm_host_mkyoung_guest, addr >> PAGE_SHIFT));

}