Re: [PATCH v1] KVM: kvm_io_bus_unregister_dev() should never fail

From: David Hildenbrand
Date: Thu Mar 23 2017 - 12:21:25 EST



> As this may set kvm->buses[bus_idx] to NULL, don't you also need to
> guard for bus == NULL in kvm_io_bus_destroy()? (I looked at the code on
> kvm/queue.)

very right, so something like this?

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e1be4b4..ef1aa7f 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -728,7 +728,8 @@ 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++) {
- kvm_io_bus_destroy(kvm->buses[i]);
+ if (kvm->buses[i])
+ kvm_io_bus_destroy(kvm->buses[i]);
kvm->buses[i] = NULL;
}
kvm_coalesced_mmio_free(kvm);

Thanks!

>
>> synchronize_srcu_expedited(&kvm->srcu);
>> kfree(bus);
>> - return r;
>> + return;
>> }
>


--

Thanks,

David