diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 8f56426aa1e3..4e5a0db68799 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -584,6 +584,7 @@ struct kvm_memory_slot {
 	struct file *private_file;
 	loff_t private_offset;
 	struct memfile_notifier notifier;
+	struct kvm *kvm;
 };
 
 static inline bool kvm_slot_can_be_private(const struct kvm_memory_slot *slot)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index bb714c2a4b06..d6f7e074cab2 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -941,6 +941,63 @@ static int kvm_vm_ioctl_set_encrypted_region(struct kvm *kvm, unsigned int ioctl
 
 	return r;
 }
+
+static void kvm_memfile_notifier_invalidate(struct memfile_notifier *notifier,
+					    pgoff_t start, pgoff_t end)
+{
+	struct kvm_memory_slot *slot = container_of(notifier,
+						    struct kvm_memory_slot,
+						    notifier);
+	unsigned long base_pgoff = slot->private_offset >> PAGE_SHIFT;
+	gfn_t start_gfn = slot->base_gfn;
+	gfn_t end_gfn = slot->base_gfn + slot->npages;
+
+
+	if (start > base_pgoff)
+		start_gfn = slot->base_gfn + start - base_pgoff;
+
+	if (end < base_pgoff + slot->npages)
+		end_gfn = slot->base_gfn + end - base_pgoff;
+
+	if (start_gfn >= end_gfn)
+		return;
+
+	kvm_zap_gfn_range(slot->kvm, start_gfn, end_gfn);
+}
+
+static struct memfile_notifier_ops kvm_memfile_notifier_ops = {
+	.invalidate = kvm_memfile_notifier_invalidate,
+};
+
+#define KVM_MEMFILE_FLAGS (MEMFILE_F_USER_INACCESSIBLE | \
+			   MEMFILE_F_UNMOVABLE | \
+			   MEMFILE_F_UNRECLAIMABLE)
+
+static inline int kvm_private_mem_register(struct kvm_memory_slot *slot)
+{
+	slot->notifier.ops = &kvm_memfile_notifier_ops;
+	return memfile_register_notifier(slot->private_file, KVM_MEMFILE_FLAGS,
+					 &slot->notifier);
+}
+
+static inline void kvm_private_mem_unregister(struct kvm_memory_slot *slot)
+{
+	memfile_unregister_notifier(&slot->notifier);
+}
+
+#else /* !CONFIG_HAVE_KVM_PRIVATE_MEM */
+
+static inline int kvm_private_mem_register(struct kvm_memory_slot *slot)
+{
+	WARN_ON_ONCE(1);
+	return -EOPNOTSUPP;
+}
+
+static inline void kvm_private_mem_unregister(struct kvm_memory_slot *slot)
+{
+	WARN_ON_ONCE(1);
+}
+
 #endif /* CONFIG_HAVE_KVM_PRIVATE_MEM */
 
 #ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
@@ -987,6 +1044,11 @@ static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
 /* This does not remove the slot from struct kvm_memslots data structures */
 static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
 {
+	if (slot->flags & KVM_MEM_PRIVATE) {
+		kvm_private_mem_unregister(slot);
+		fput(slot->private_file);
+	}
+
 	kvm_destroy_dirty_bitmap(slot);
 
 	kvm_arch_free_memslot(kvm, slot);
@@ -1548,10 +1610,16 @@ bool __weak kvm_arch_private_mem_supported(struct kvm *kvm)
 	return false;
 }
 
-static int check_memory_region_flags(const struct kvm_user_mem_region *mem)
+static int check_memory_region_flags(struct kvm *kvm,
+				     const struct kvm_user_mem_region *mem)
 {
 	u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
 
+#ifdef CONFIG_HAVE_KVM_PRIVATE_MEM
+	if (kvm_arch_private_mem_supported(kvm))
+		valid_flags |= KVM_MEM_PRIVATE;
+#endif
+
 #ifdef __KVM_HAVE_READONLY_MEM
 	valid_flags |= KVM_MEM_READONLY;
 #endif
@@ -1627,6 +1695,12 @@ static int kvm_prepare_memory_region(struct kvm *kvm,
 {
 	int r;
 
+	if (change == KVM_MR_CREATE && new->flags & KVM_MEM_PRIVATE) {
+		r = kvm_private_mem_register(new);
+		if (r)
+			return r;
+	}
+
 	/*
 	 * If dirty logging is disabled, nullify the bitmap; the old bitmap
 	 * will be freed on "commit".  If logging is enabled in both old and
@@ -1655,6 +1729,9 @@ static int kvm_prepare_memory_region(struct kvm *kvm,
 	if (r && new && new->dirty_bitmap && (!old || !old->dirty_bitmap))
 		kvm_destroy_dirty_bitmap(new);
 
+	if (r && change == KVM_MR_CREATE && new->flags & KVM_MEM_PRIVATE)
+		kvm_private_mem_unregister(new);
+
 	return r;
 }
 
@@ -1952,7 +2029,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
 	int as_id, id;
 	int r;
 
-	r = check_memory_region_flags(mem);
+	r = check_memory_region_flags(kvm, mem);
 	if (r)
 		return r;
 
@@ -1971,6 +2048,10 @@ int __kvm_set_memory_region(struct kvm *kvm,
 	     !access_ok((void __user *)(unsigned long)mem->userspace_addr,
 			mem->memory_size))
 		return -EINVAL;
+	if (mem->flags & KVM_MEM_PRIVATE &&
+		(mem->private_offset & (PAGE_SIZE - 1) ||
+		 mem->private_offset > U64_MAX - mem->memory_size))
+		return -EINVAL;
 	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
 		return -EINVAL;
 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
@@ -2009,6 +2090,9 @@ int __kvm_set_memory_region(struct kvm *kvm,
 		if ((kvm->nr_memslot_pages + npages) < kvm->nr_memslot_pages)
 			return -EINVAL;
 	} else { /* Modify an existing slot. */
+		/* Private memslots are immutable, they can only be deleted. */
+		if (mem->flags & KVM_MEM_PRIVATE)
+			return -EINVAL;
 		if ((mem->userspace_addr != old->userspace_addr) ||
 		    (npages != old->npages) ||
 		    ((mem->flags ^ old->flags) & KVM_MEM_READONLY))
@@ -2037,10 +2121,27 @@ int __kvm_set_memory_region(struct kvm *kvm,
 	new->npages = npages;
 	new->flags = mem->flags;
 	new->userspace_addr = mem->userspace_addr;
+	if (mem->flags & KVM_MEM_PRIVATE) {
+		new->private_file = fget(mem->private_fd);
+		if (!new->private_file) {
+			r = -EINVAL;
+			goto out;
+		}
+		new->private_offset = mem->private_offset;
+	}
+
+	new->kvm = kvm;
 
 	r = kvm_set_memslot(kvm, old, new, change);
 	if (r)
-		kfree(new);
+		goto out;
+
+	return 0;
+
+out:
+	if (new->private_file)
+		fput(new->private_file);
+	kfree(new);
 	return r;
 }
 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
@@ -4712,12 +4813,10 @@ static long kvm_vm_ioctl(struct file *filp,
 			(u32 __user *)(argp + offsetof(typeof(mem), flags))))
 			goto out;
 
-		if (flags & KVM_MEM_PRIVATE) {
-			r = -EINVAL;
-			goto out;
-		}
-
-		size = sizeof(struct kvm_userspace_memory_region);
+		if (flags & KVM_MEM_PRIVATE)
+			size = sizeof(struct kvm_userspace_memory_region_ext);
+		else
+			size = sizeof(struct kvm_userspace_memory_region);
 
 		if (copy_from_user(&mem, argp, size))
 			goto out;
