Merge branch 'annotations' of git://git.kernel.org/pub/scm/linux/kernel/git/borntraeger/linux into kvm-master

3 files changed, 31 insertions, 17 deletions

diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 9120edf3c94b..f2ac53ab8243 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -825,7 +825,7 @@ static int kvm_assign_ioeventfd_idx(struct kvm *kvm,
         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 @@ kvm_deassign_ioeventfd_idx(struct kvm *kvm, enum kvm_bus bus_idx,
 {
         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 @@ kvm_deassign_ioeventfd_idx(struct kvm *kvm, enum kvm_bus bus_idx,
                         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 --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
index 31e40c9e81df..b1286c4e0712 100644
--- a/virt/kvm/irqchip.c
+++ b/virt/kvm/irqchip.c
@@ -230,7 +230,7 @@ int kvm_set_irq_routing(struct kvm *kvm,
         }
 
         mutex_lock(&kvm->irq_lock);
-        old = kvm->irq_routing;
+        old = rcu_dereference_protected(kvm->irq_routing, 1);
         rcu_assign_pointer(kvm->irq_routing, new);
         kvm_irq_routing_update(kvm);
         kvm_arch_irq_routing_update(kvm);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0d796c9a6482..7766c2b52797 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -299,7 +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 +685,8 @@ static struct kvm *kvm_create_vm(unsigned long type)
         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 +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 +747,11 @@ static void kvm_destroy_vm(struct kvm *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 +763,8 @@ static void kvm_destroy_vm(struct kvm *kvm)
         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 +2567,14 @@ static long kvm_vcpu_ioctl(struct file *filp,
         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 +2585,7 @@ static long kvm_vcpu_ioctl(struct file *filp,
                 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 +3581,7 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
 {
         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 +3610,7 @@ void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
         int i;
         struct kvm_io_bus *new_bus, *bus;
 
-        bus = kvm->buses[bus_idx];
+        bus = kvm_get_bus(kvm, bus_idx);
         if (!bus)
                 return;