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

5 files changed, 16 insertions, 20 deletions

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index f5104b7c52cd..463fb3bbe11e 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/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)
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index ddc485a529f2..c3beaeef3f60 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/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);
 }
 
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 01294a5099dd..108d1f580177 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/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);
                 }
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index b8ba6e4a27e4..e554e5ad2fe8 100644
--- a/arch/x86/kernel/kvm.c
+++ b/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
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 91a5e989abcf..185a2b823a2d 100644
--- a/arch/x86/kvm/x86.c
+++ b/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)