Using virtio_random

[John Nielsen]

Hi all-

I am happy to see that virtio_random(4) will be included in FreeBSD 10.1. To try it out, I loaded up BETA1 in a virtual machine with entropy passthrough enabled. After booting it with the virtio_random module loaded I see this in dmesg:

virtio_pci3: <VirtIO PCI Entropy adapter> port 0xc0a0-0xc0bf irq 10 at device 6.0 on pci0                                                                                                    
vtrnd0: <VirtIO Entropy Adapter> on virtio_pci3                                                                                                                                              
virtio_pci3: host features: 0x71000000 <EventIdx,RingIndirect,NotifyOnEmpty>                                                                                                                 
virtio_pci3: negotiated features: 0                                                                                                                                                          

So far, so good. (I think? The 'negotiated features: 0' gives me pause..)

Now how do I use the driver as an entropy source (or verify that it's being used)? I don't see any difference in the output of "sysctl kern.random" with or without the driver loaded. Is something missing?

Thanks,

JN