tree 12549a0a41cdda2b265bf0107daca828bc52b8c5
parent bcb85c887647c0f096b51ac2ee391ea792b14b9e
author David Hildenbrand <david@redhat.com> 1493391980 +0200
committer Paolo Bonzini <pbonzini@redhat.com> 1493729145 +0200

KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING

We needed the lock to avoid racing with creation of the irqchip on x86. As
kvm_set_irq_routing() calls srcu_synchronize_expedited(), this lock
might be held for a longer time.

Let's introduce an arch specific callback to check if we can actually
add irq routes. For x86, all we have to do is check if we have an
irqchip in the kernel. We don't need kvm->lock at that point as the
irqchip is marked as inititalized only when actually fully created.

Reported-by: Steve Rutherford <srutherford@google.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Fixes: 1df6ddede10a ("KVM: x86: race between KVM_SET_GSI_ROUTING and KVM_CREATE_IRQCHIP")
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>