Merge branch 'annotations' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeg...

diff --combined virt/kvm/eventfd.c
index 9120edf3c94bfccd1e34a625d163385abbd3cbc8,d016aadd5fbb633d60189502e42e156c3ff6ed64..f2ac53ab82438f0b473ecd8ed91b1e2548af7ca2
--- 1/virt/kvm/eventfd.c
--- 2/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@@ -184,7 -184,7 +184,7 @@@ int __attribute__((weak)) kvm_arch_set_
   * Called with wqh->lock held and interrupts disabled
   */
  static int
 -irqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
 +irqfd_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync, void *key)
  {
        struct kvm_kernel_irqfd *irqfd =
                container_of(wait, struct kvm_kernel_irqfd, wait);
@@@ -825,7 -825,7 +825,7 @@@ static int kvm_assign_ioeventfd_idx(str
        if (ret < 0)
                goto unlock_fail;
  
-       kvm->buses[bus_idx]->ioeventfd_count++;
+       kvm_get_bus(kvm, bus_idx)->ioeventfd_count++;
        list_add_tail(&p->list, &kvm->ioeventfds);
  
        mutex_unlock(&kvm->slots_lock);
@@@ -848,6 -848,7 +848,7 @@@ kvm_deassign_ioeventfd_idx(struct kvm *
  {
        struct _ioeventfd        *p, *tmp;
        struct eventfd_ctx       *eventfd;
+       struct kvm_io_bus        *bus;
        int                       ret = -ENOENT;
  
        eventfd = eventfd_ctx_fdget(args->fd);
@@@ -870,8 -871,9 +871,9 @@@
                        continue;
  
                kvm_io_bus_unregister_dev(kvm, bus_idx, &p->dev);
-               if (kvm->buses[bus_idx])
-                       kvm->buses[bus_idx]->ioeventfd_count--;
+               bus = kvm_get_bus(kvm, bus_idx);
+               if (bus)
+                       bus->ioeventfd_count--;
                ioeventfd_release(p);
                ret = 0;
                break;

diff --combined virt/kvm/kvm_main.c
index 0d796c9a64824dae07cc5c999abe41ada3496723,6e6d4edf0e92311d7c48ca18aab53603d56fe3bc..7766c2b5279794413345225377e199ca56ea42ed
--- 1/virt/kvm/kvm_main.c
--- 2/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@@ -187,23 -187,12 +187,23 @@@ static void ack_flush(void *_completed
  {
  }
  
 +static inline bool kvm_kick_many_cpus(const struct cpumask *cpus, bool wait)
 +{
 +      if (unlikely(!cpus))
 +              cpus = cpu_online_mask;
 +
 +      if (cpumask_empty(cpus))
 +              return false;
 +
 +      smp_call_function_many(cpus, ack_flush, NULL, wait);
 +      return true;
 +}
 +
  bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
  {
        int i, cpu, me;
        cpumask_var_t cpus;
 -      bool called = true;
 -      bool wait = req & KVM_REQUEST_WAIT;
 +      bool called;
        struct kvm_vcpu *vcpu;
  
        zalloc_cpumask_var(&cpus, GFP_ATOMIC);
@@@ -218,9 -207,14 +218,9 @@@
  
                if (cpus != NULL && cpu != -1 && cpu != me &&
                    kvm_request_needs_ipi(vcpu, req))
 -                      cpumask_set_cpu(cpu, cpus);
 +                      __cpumask_set_cpu(cpu, cpus);
        }
 -      if (unlikely(cpus == NULL))
 -              smp_call_function_many(cpu_online_mask, ack_flush, NULL, wait);
 -      else if (!cpumask_empty(cpus))
 -              smp_call_function_many(cpus, ack_flush, NULL, wait);
 -      else
 -              called = false;
 +      called = kvm_kick_many_cpus(cpus, !!(req & KVM_REQUEST_WAIT));
        put_cpu();
        free_cpumask_var(cpus);
        return called;
@@@ -299,7 -293,12 +299,12 @@@ EXPORT_SYMBOL_GPL(kvm_vcpu_init)
  
  void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
  {
-       put_pid(vcpu->pid);
+       /*
+        * no need for rcu_read_lock as VCPU_RUN is the only place that
+        * will change the vcpu->pid pointer and on uninit all file
+        * descriptors are already gone.
+        */
+       put_pid(rcu_dereference_protected(vcpu->pid, 1));
        kvm_arch_vcpu_uninit(vcpu);
        free_page((unsigned long)vcpu->run);
  }
@@@ -680,8 -679,8 +685,8 @@@ static struct kvm *kvm_create_vm(unsign
        if (init_srcu_struct(&kvm->irq_srcu))
                goto out_err_no_irq_srcu;
        for (i = 0; i < KVM_NR_BUSES; i++) {
-               kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
-                                       GFP_KERNEL);
+               rcu_assign_pointer(kvm->buses[i],
+                       kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL));
                if (!kvm->buses[i])
                        goto out_err;
        }
@@@ -706,9 -705,10 +711,10 @@@ out_err_no_srcu
        hardware_disable_all();
  out_err_no_disable:
        for (i = 0; i < KVM_NR_BUSES; i++)
-               kfree(kvm->buses[i]);
+               kfree(rcu_access_pointer(kvm->buses[i]));
        for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
-               kvm_free_memslots(kvm, kvm->memslots[i]);
+               kvm_free_memslots(kvm,
+                       rcu_dereference_protected(kvm->memslots[i], 1));
        kvm_arch_free_vm(kvm);
        mmdrop(current->mm);
        return ERR_PTR(r);
@@@ -741,8 -741,11 +747,11 @@@ static void kvm_destroy_vm(struct kvm *
        spin_unlock(&kvm_lock);
        kvm_free_irq_routing(kvm);
        for (i = 0; i < KVM_NR_BUSES; i++) {
-               if (kvm->buses[i])
-                       kvm_io_bus_destroy(kvm->buses[i]);
+               struct kvm_io_bus *bus;
+ 
+               bus = rcu_dereference_protected(kvm->buses[i], 1);
+               if (bus)
+                       kvm_io_bus_destroy(bus);
                kvm->buses[i] = NULL;
        }
        kvm_coalesced_mmio_free(kvm);
@@@ -754,7 -757,8 +763,8 @@@
        kvm_arch_destroy_vm(kvm);
        kvm_destroy_devices(kvm);
        for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
-               kvm_free_memslots(kvm, kvm->memslots[i]);
+               kvm_free_memslots(kvm,
+                       rcu_dereference_protected(kvm->memslots[i], 1));
        cleanup_srcu_struct(&kvm->irq_srcu);
        cleanup_srcu_struct(&kvm->srcu);
        kvm_arch_free_vm(kvm);
@@@ -2557,13 -2561,14 +2567,14 @@@ static long kvm_vcpu_ioctl(struct file 
        if (r)
                return r;
        switch (ioctl) {
-       case KVM_RUN:
+       case KVM_RUN: {
+               struct pid *oldpid;
                r = -EINVAL;
                if (arg)
                        goto out;
-               if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
+               oldpid = rcu_access_pointer(vcpu->pid);
+               if (unlikely(oldpid != current->pids[PIDTYPE_PID].pid)) {
                        /* The thread running this VCPU changed. */
-                       struct pid *oldpid = vcpu->pid;
                        struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
  
                        rcu_assign_pointer(vcpu->pid, newpid);
@@@ -2574,6 -2579,7 +2585,7 @@@
                r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
                trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
                break;
+       }
        case KVM_GET_REGS: {
                struct kvm_regs *kvm_regs;
  
@@@ -3569,7 -3575,7 +3581,7 @@@ int kvm_io_bus_register_dev(struct kvm 
  {
        struct kvm_io_bus *new_bus, *bus;
  
-       bus = kvm->buses[bus_idx];
+       bus = kvm_get_bus(kvm, bus_idx);
        if (!bus)
                return -ENOMEM;
  
@@@ -3598,7 -3604,7 +3610,7 @@@ void kvm_io_bus_unregister_dev(struct k
        int i;
        struct kvm_io_bus *new_bus, *bus;
  
-       bus = kvm->buses[bus_idx];
+       bus = kvm_get_bus(kvm, bus_idx);
        if (!bus)
                return;