Merge git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Avi Kivity:
 "Two asynchronous page fault fixes (one guest, one host), a powerpc
  page refcount fix, and an ia64 build fix."

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: ia64: fix build due to typo
  KVM: PPC: Book3S HV: Fix refcounting of hugepages
  KVM: Do not take reference to mm during async #PF
  KVM: ensure async PF event wakes up vcpu from halt

arch/ia64/kvm/kvm-ia64.c

@@ -1174,7 +1174,7 @@ out:
 
 bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu)
 {
-	return irqchip_in_kernel(vcpu->kcm) == (vcpu->arch.apic != NULL);
+	return irqchip_in_kernel(vcpu->kvm) == (vcpu->arch.apic != NULL);
 }
 
 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)

arch/powerpc/kvm/book3s_64_mmu_hv.c

@@ -258,6 +258,8 @@ static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
 			    !(memslot->userspace_addr & (s - 1))) {
 				start &= ~(s - 1);
 				pgsize = s;
+				get_page(hpage);
+				put_page(page);
 				page = hpage;
 			}
 		}
@@ -281,11 +283,8 @@ static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
 	err = 0;
 
  out:
-	if (got) {
-		if (PageHuge(page))
-			page = compound_head(page);
+	if (got)
 		put_page(page);
-	}
 	return err;
 
  up_err:
@@ -678,8 +677,15 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		SetPageDirty(page);
 
  out_put:
-	if (page)
-		put_page(page);
+	if (page) {
+		/*
+		 * We drop pages[0] here, not page because page might
+		 * have been set to the head page of a compound, but
+		 * we have to drop the reference on the correct tail
+		 * page to match the get inside gup()
+		 */
+		put_page(pages[0]);
+	}
 	return ret;
 
  out_unlock:
@@ -979,6 +985,7 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
 			pa = *physp;
 		}
 		page = pfn_to_page(pa >> PAGE_SHIFT);
+		get_page(page);
 	} else {
 		hva = gfn_to_hva_memslot(memslot, gfn);
 		npages = get_user_pages_fast(hva, 1, 1, pages);
@@ -991,8 +998,6 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
 		page = compound_head(page);
 		psize <<= compound_order(page);
 	}
-	if (!kvm->arch.using_mmu_notifiers)
-		get_page(page);
 	offset = gpa & (psize - 1);
 	if (nb_ret)
 		*nb_ret = psize - offset;
@@ -1003,7 +1008,6 @@ void kvmppc_unpin_guest_page(struct kvm *kvm, void *va)
 {
 	struct page *page = virt_to_page(va);
 
-	page = compound_head(page);
 	put_page(page);
 }
 

arch/powerpc/kvm/book3s_hv.c

@@ -1192,8 +1192,6 @@ static void unpin_slot(struct kvm *kvm, int slot_id)
 				continue;
 			pfn = physp[j] >> PAGE_SHIFT;
 			page = pfn_to_page(pfn);
-			if (PageHuge(page))
-				page = compound_head(page);
 			SetPageDirty(page);
 			put_page(page);
 		}

arch/x86/kernel/kvm.c

@@ -79,7 +79,6 @@ struct kvm_task_sleep_node {
 	u32 token;
 	int cpu;
 	bool halted;
-	struct mm_struct *mm;
 };
 
 static struct kvm_task_sleep_head {
@@ -126,9 +125,7 @@ void kvm_async_pf_task_wait(u32 token)
 
 	n.token = token;
 	n.cpu = smp_processor_id();
-	n.mm = current->active_mm;
 	n.halted = idle || preempt_count() > 1;
-	atomic_inc(&n.mm->mm_count);
 	init_waitqueue_head(&n.wq);
 	hlist_add_head(&n.link, &b->list);
 	spin_unlock(&b->lock);
@@ -161,9 +158,6 @@ EXPORT_SYMBOL_GPL(kvm_async_pf_task_wait);
 static void apf_task_wake_one(struct kvm_task_sleep_node *n)
 {
 	hlist_del_init(&n->link);
-	if (!n->mm)
-		return;
-	mmdrop(n->mm);
 	if (n->halted)
 		smp_send_reschedule(n->cpu);
 	else if (waitqueue_active(&n->wq))
@@ -207,7 +201,7 @@ again:
 		 * async PF was not yet handled.
 		 * Add dummy entry for the token.
 		 */
-		n = kmalloc(sizeof(*n), GFP_ATOMIC);
+		n = kzalloc(sizeof(*n), GFP_ATOMIC);
 		if (!n) {
 			/*
 			 * Allocation failed! Busy wait while other cpu
@@ -219,7 +213,6 @@ again:
 		}
 		n->token = token;
 		n->cpu = smp_processor_id();
-		n->mm = NULL;
 		init_waitqueue_head(&n->wq);
 		hlist_add_head(&n->link, &b->list);
 	} else

arch/x86/kvm/x86.c

@@ -6581,6 +6581,7 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
 		kvm_inject_page_fault(vcpu, &fault);
 	}
 	vcpu->arch.apf.halted = false;
+	vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
 }
 
 bool kvm_arch_can_inject_async_page_present(struct kvm_vcpu *vcpu)