Re: [PATCH] hw/pci: Fix crash when running QEMU with "-nic model=rocker"

[Laurent Vivier]

Le 27/05/2020 à 17:31, Thomas Huth a écrit :
> QEMU currently aborts when being started with "-nic model=rocker" or with
> "-net nic,model=rocker". This happens because the "rocker" device is not
> a normal NIC but a switch, which has different properties. Thus we should
> only consider real NIC devices for "-nic" and "-net". These devices can
> be identified by the "netdev" property, so check for this property before
> adding the device to the list.
> 
> Reported-by: Michael Tokarev <mjt@tls.msk.ru>
> Fixes: 52310c3fa7dc854d ("net: allow using any PCI NICs in -net or -nic")
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  hw/pci/pci.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 70c66965f5..46214f8287 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -1887,7 +1887,18 @@ PCIDevice *pci_nic_init_nofail(NICInfo *nd, PCIBus 
> *rootbus,
>          if (test_bit(DEVICE_CATEGORY_NETWORK, dc->categories) &&
>              dc->user_creatable) {
>              const char *name = object_class_get_name(list->data);
> -            g_ptr_array_add(pci_nic_models, (gpointer)name);
> +            /*
> +             * A network device might also be something else than a NIC, see
> +             * e.g. the "rocker" device. Thus we have to look for the 
> "netdev"
> +             * property, too. Unfortunately, some devices like virtio-net 
> only
> +             * create this property during instance_init, so we have to 
> create
> +             * a temporary instance here to be able to check it.
> +             */
> +            Object *obj = object_new_with_class(OBJECT_CLASS(dc));
> +            if (object_property_find(obj, "netdev", NULL)) {
> +                g_ptr_array_add(pci_nic_models, (gpointer)name);
> +            }
> +            object_unref(obj);
>          }
>          next = list->next;
>          g_slist_free_1(list);
> 

Not really trivial, I will not pick up this patch via trivial-branch,
unless PCI maintainers request it.

Thanks,
Laurent