Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1df6dded authored by David Hildenbrand's avatar David Hildenbrand Committed by Radim Krčmář
Browse files

KVM: x86: race between KVM_SET_GSI_ROUTING and KVM_CREATE_IRQCHIP 



Avoid races between KVM_SET_GSI_ROUTING and KVM_CREATE_IRQCHIP by taking
the kvm->lock when setting up routes.

If KVM_CREATE_IRQCHIP fails, KVM_SET_GSI_ROUTING could have already set
up routes pointing at pic/ioapic, being silently removed already.

Also, as a side effect, this patch makes sure that KVM_SET_GSI_ROUTING
and KVM_CAP_SPLIT_IRQCHIP cannot run in parallel.

Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Signed-off-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
parent f7b1a77d

virt/kvm/kvm_main.c

+3 −0
Original line number Diff line number Diff line
@@ -3069,8 +3069,11 @@ static long kvm_vm_ioctl(struct file *filp, 
					   routing.nr * sizeof(*entries)))

				goto out_free_irq_routing;

		}

		/* avoid races with KVM_CREATE_IRQCHIP on x86 */

		mutex_lock(&kvm->lock);

		r = kvm_set_irq_routing(kvm, entries, routing.nr,

					routing.flags);

		mutex_unlock(&kvm->lock);

out_free_irq_routing:

		vfree(entries);

		break;