port-sparc64/57289: qemu-system-sparc64 virtio-net-pci device doesn't work on NetBSD 10.0 - locks up

[mike%papersolve.com@localhost]

>Number:         57289
>Category:       port-sparc64
>Synopsis:       qemu-system-sparc64 virtio-net-pci device doesn't work on NetBSD 10.0 - locks up
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-sparc64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 24 19:05:00 +0000 2023
>Originator:     Mike Russo
>Release:        10.0_BETA
>Organization:
>Environment:
NetBSD  10.0_BETA NetBSD 10.0_BETA (GENERIC) #0: Mon Mar 20 17:25:14 UTC 2023  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/sparc64/compile/GENERIC sparc64
>Description:
I am attempting to use virtio-net driver with qemu-system-sparc64; in previous versions of NetBSD the device is detected but does not get configured.  In 10.0 BETA that I downloaded today, it shows up but hangs when trying to configure it.  

Command line used to start qemu:
qemu-system-sparc64 -cdrom ./NetBSD-10.0_BETA-sparc64.iso -m 2048 -net nic,model=virtio-net-pci -net user -nographic -boot d

(used latest qemu compiled from source today)

Quit install, it is detected:

# dmesg|grep virtio
[     1.000000] virtio0 at pci2 dev 0 function 0
[     1.000000] virtio0: network device (id 1, rev. 0x00)
[     1.000000] vioif0 at virtio0: features: 0x31870020<EVENT_IDX,INDIRECT_DESC,NOTIFY_ON_EMPTY,CTRL_MAC,CTRL_RX,CTRL_VQ,STATUS,MAC>
[     1.000000] virtio0: allocated 20480 byte for virtqueue 0 for rx0, size 256
[     1.000000] virtio0: using 8192 byte (512 entries) indirect descriptors
[     1.000000] virtio0: allocated 81920 byte for virtqueue 1 for tx0, size 256
[     1.000000] virtio0: using 69632 byte (4352 entries) indirect descriptors
[     1.000000] virtio0: allocated 8192 byte for virtqueue 2 for control, size 64
[     1.000000] virtio0: interrupting at ivec 3010


Shows as interface:
# ifconfig 
vioif0: flags=0x8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
        ec_capabilities=0x1<VLAN_MTU>
        ec_enabled=0
        address: 52:54:00:12:34:56
lo0: flags=0x8048<LOOPBACK,RUNNING,MULTICAST> mtu 33112
        status: active

Hangs when trying to configure:
# ifconfig vioif0 10.0.2.15/24

//machine locks up here
>How-To-Repeat:
boot NetBSD ISO as shown in description and attempt to configure interface
>Fix: