diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h index 586026e85903..2d71f686064a 100644 --- a/arch/arm64/include/asm/kvm_nested.h +++ b/arch/arm64/include/asm/kvm_nested.h @@ -78,6 +78,9 @@ extern void kvm_s2_mmu_iterate_by_vmid(struct kvm *kvm, u16 vmid, const union tlbi_info *info, void (*)(struct kvm_s2_mmu *, const union tlbi_info *)); +extern void kvm_record_guest_s2_mapping(struct kvm_s2_mmu *mmu, gpa_t canonical_ipa, + gpa_t nested_ipa, size_t map_size, + struct kvm_guest_s2_mapping *mapping); extern void kvm_vcpu_load_hw_mmu(struct kvm_vcpu *vcpu); extern void kvm_vcpu_put_hw_mmu(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 4467f51547a4..f8d3b7fe631f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1645,6 +1645,7 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) enum kvm_pgtable_walk_flags flags = KVM_PGTABLE_WALK_SHARED; enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R; struct kvm_pgtable *pgt = s2fd->vcpu->arch.hw_mmu->pgt; + struct kvm_guest_s2_mapping *mapping = NULL; unsigned long mmu_seq; struct page *page; struct kvm *kvm = s2fd->vcpu->kvm; @@ -1658,6 +1659,11 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) ret = topup_mmu_memcache(s2fd->vcpu, memcache); if (ret) return ret; + if (kvm_is_nested_s2_mmu(kvm, pgt->mmu)) { + mapping = kmalloc_obj(struct kvm_guest_s2_mapping, GFP_KERNEL_ACCOUNT); + if (!mapping) + return -ENOMEM; + } } if (s2fd->nested) @@ -1678,6 +1684,7 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) if (ret) { kvm_prepare_memory_fault_exit(s2fd->vcpu, s2fd->fault_ipa, PAGE_SIZE, write_fault, exec_fault, false); + kfree(mapping); return ret; } @@ -1711,11 +1718,22 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) ret = KVM_PGT_FN(kvm_pgtable_stage2_map)(pgt, s2fd->fault_ipa, PAGE_SIZE, __pfn_to_phys(pfn), prot, memcache, flags); + /* + * -EAGAIN from kvm_pgtable_stage2_map() can install mappings. + * We don't know which subrange is installed, track the whole + * thing. + */ + if ((ret == 0 || ret == -EAGAIN) && kvm_is_nested_s2_mmu(kvm, pgt->mmu)) { + kvm_record_guest_s2_mapping(pgt->mmu, gfn << PAGE_SHIFT, + s2fd->fault_ipa, PAGE_SIZE, mapping); + mapping = NULL; + } } out_unlock: kvm_release_faultin_page(kvm, page, !!ret, prot & KVM_PGTABLE_PROT_W); kvm_fault_unlock(kvm); + kfree(mapping); if ((prot & KVM_PGTABLE_PROT_W) && !ret) mark_page_dirty_in_slot(kvm, s2fd->memslot, gfn); @@ -2052,6 +2070,7 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, void *memcache) { enum kvm_pgtable_walk_flags flags = KVM_PGTABLE_WALK_SHARED; + struct kvm_guest_s2_mapping *mapping = NULL; bool writable = prot & KVM_PGTABLE_PROT_W; struct kvm *kvm = s2fd->vcpu->kvm; phys_addr_t canonical_ipa; @@ -2062,6 +2081,15 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, gfn_t gfn; int ret; + if (kvm_is_nested_s2_mmu(kvm, s2fd->vcpu->arch.hw_mmu)) { + mapping = kmalloc_obj(struct kvm_guest_s2_mapping, + GFP_KERNEL_ACCOUNT); + if (!mapping) { + kvm_release_page_unused(s2vi->page); + return -ENOMEM; + } + } + kvm_fault_lock(kvm); pgt = s2fd->vcpu->arch.hw_mmu->pgt; ret = -EAGAIN; @@ -2115,11 +2143,22 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, ret = KVM_PGT_FN(kvm_pgtable_stage2_map)(pgt, gfn_to_gpa(gfn), mapping_size, __pfn_to_phys(pfn), prot, memcache, flags); + /* + * -EAGAIN from kvm_pgtable_stage2_map() can install mappings. + * We don't know which subrange is installed, track the whole + * thing. + */ + if ((ret == 0 || ret == -EAGAIN) && kvm_is_nested_s2_mmu(kvm, pgt->mmu)) { + kvm_record_guest_s2_mapping(pgt->mmu, canonical_ipa, + gfn_to_gpa(gfn), mapping_size, mapping); + mapping = NULL; + } } out_unlock: kvm_release_faultin_page(kvm, s2vi->page, !!ret, writable); kvm_fault_unlock(kvm); + kfree(mapping); /* * Mark the page dirty only if the fault is handled successfully, diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c index 81ba9c8532f4..f5f0e364e56f 100644 --- a/arch/arm64/kvm/nested.c +++ b/arch/arm64/kvm/nested.c @@ -5,6 +5,7 @@ */ #include +#include #include #include @@ -872,6 +873,30 @@ static struct kvm_s2_mmu *get_s2_mmu_nested(struct kvm_vcpu *vcpu) return s2_mmu; } +void kvm_record_guest_s2_mapping(struct kvm_s2_mmu *mmu, gpa_t canonical_ipa, + gpa_t nested_ipa, size_t map_size, + struct kvm_guest_s2_mapping *mapping) +{ + struct kvm *kvm = kvm_s2_mmu_to_kvm(mmu); + + lockdep_assert_held_read(&kvm->mmu_lock); + + canonical_ipa = ALIGN_DOWN(canonical_ipa, map_size); + nested_ipa = ALIGN_DOWN(nested_ipa, map_size); + + mapping->canonical.start = canonical_ipa; + mapping->canonical.last = canonical_ipa + map_size - 1; + + mapping->nested.start = nested_ipa; + mapping->nested.last = nested_ipa + map_size - 1; + + mapping->nested_mmu = mmu; + + guard(spinlock)(&kvm->arch.guest_s2_tracking_lock); + interval_tree_insert(&mapping->nested, &mmu->guest_s2_mappings); + interval_tree_insert(&mapping->canonical, &kvm->arch.mmu.guest_s2_mappings); +} + void kvm_init_nested_s2_mmu(struct kvm_s2_mmu *mmu) { /* CnP being set denotes an invalid entry */