diff options
| -rw-r--r-- | include/linux/kvm_host.h | 8 | ||||
| -rw-r--r-- | virt/kvm/eventfd.c | 8 | ||||
| -rw-r--r-- | virt/kvm/kvm_main.c | 17 |
3 files changed, 22 insertions, 11 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index bcd37b855c66..6a164f9eb02c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -404,7 +404,7 @@ struct kvm { int last_boosted_vcpu; struct list_head vm_list; struct mutex lock; - struct kvm_io_bus *buses[KVM_NR_BUSES]; + struct kvm_io_bus __rcu *buses[KVM_NR_BUSES]; #ifdef CONFIG_HAVE_KVM_EVENTFD struct { spinlock_t lock; @@ -473,6 +473,12 @@ struct kvm { #define vcpu_err(vcpu, fmt, ...) \ kvm_err("vcpu%i " fmt, (vcpu)->vcpu_id, ## __VA_ARGS__) +static inline struct kvm_io_bus *kvm_get_bus(struct kvm *kvm, enum kvm_bus idx) +{ + return srcu_dereference_check(kvm->buses[idx], &kvm->srcu, + lockdep_is_held(&kvm->slots_lock)); +} + static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i) { /* Pairs with smp_wmb() in kvm_vm_ioctl_create_vcpu, in case diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index a8d540398bbd..d016aadd5fbb 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/kvm_main.c b/virt/kvm/kvm_main.c index fc2d58312fd5..d76e822f8929 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -679,8 +679,8 @@ 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; } @@ -705,7 +705,7 @@ 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_arch_free_vm(kvm); @@ -740,8 +740,11 @@ 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); @@ -3570,7 +3573,7 @@ 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; @@ -3599,7 +3602,7 @@ 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; |