KVM: Properly lock PIT creation

Otherwise, two threads can create a PIT in parallel and cause a memory leak.

Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Avi Kivity 2009-01-05 15:21:42 +02:00
parent a77ab5ead5
commit 269e05e485
2 changed files with 6 additions and 2 deletions

View File

@ -548,9 +548,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm)
if (!pit)
return NULL;
mutex_lock(&kvm->lock);
pit->irq_source_id = kvm_request_irq_source_id(kvm);
mutex_unlock(&kvm->lock);
if (pit->irq_source_id < 0) {
kfree(pit);
return NULL;

View File

@ -1837,10 +1837,16 @@ long kvm_arch_vm_ioctl(struct file *filp,
goto out;
break;
case KVM_CREATE_PIT:
mutex_lock(&kvm->lock);
r = -EEXIST;
if (kvm->arch.vpit)
goto create_pit_unlock;
r = -ENOMEM;
kvm->arch.vpit = kvm_create_pit(kvm);
if (kvm->arch.vpit)
r = 0;
create_pit_unlock:
mutex_unlock(&kvm->lock);
break;
case KVM_IRQ_LINE: {
struct kvm_irq_level irq_event;