I'm pleased to share some significant updates that have recently been released for our Hypervisor and Virtualization frameworks. We've focused on enhancing efficiency, expanding capabilities, and addressing common developer needs. I believe these will be valuable for many of you. Here’s a look at what’s new: Hypervisor Updates We've introduced support for configuring the intermediate physical address (IPA) memory granularity of a VM. This allows for more granular memory mappings, enabling granularity sizes down to 4KB. This is particularly useful for certain specialized device drivers requiring finer memory control. Virtualization Framework Updates More Efficient VM Image Storage with ASIF: We've integrated support for the Apple Sparse Image Format (ASIF). This results in a smaller disk footprint and optimized transfer for VM disk images when using VZDiskImageStorageDeviceAttachment, improving storage efficiency. Custom Network Topologies with vmnet: We've added support for vmnet custom network topologies. This enables more flexible VM-to-VM communication based on logical networks with customized configurations, useful for complex testing or development environments. See VZVmnetNetworkDeviceAttachment to get started. Simplified VM Queue Discovery: It's now easier to discover a VM’s on-process thanks to a new property on VZVirtualMachine. This should aid in development and debugging when interacting directly with the VM's queue. These are some of the key highlights of the first beta, and I'm looking forward to seeing how these improvements will be utilized. I encourage you to explore the documentation for full details on these features.

Hey there! I’ve got some exciting news about Apple’s virtio_net_hdr implementation on macOS 15.4. It’s making communication a lot smoother, with a noticeable improvement! Now, I’d love to hear your thoughts on a couple of things. First, how do you think we can validate the populated values? And secondly, should we consider reusing populated values for the other endpoint, like the ‘flags’ field? Your insights would be invaluable!

Here's a simple program that spoofs an ARP reply for a given IP address. If I spin up two terminal sessions on the same machine. Run this code in one window % ./spoof en0 192.168.1.7 Listening on en0 for ARP requests to 192.168.1.7 Spoofing MAC: 00:0c:87:47:50:27 And in the second window cause the OS to issue an ARP_REQ % ping 192.168.1.7 You will see the program respond to the ARP request. (Wireshark will see the ARP_REQ and ARP_REPLY packets) however my arp table isn't updated with the MAC for the IP address. There is no firewall active. % arp -a|grep 192.168.1.7 (192.168.1.7) at (incomplete) on en0 ifscope [ethernet] This is running on a MacBook pro M3 (OSX 15.4). HOWEVER, on a MacBook pro M4 (OSX 15.2) is does Work !!!!! Can anyone explain why its not working? spoof.txt

Hi, I have couple of inquiries regarding the vmnet framework: Incorporating Global Variables: How should we integrate the new global variables in macOS 15.0+ vmnet_read_max_packets_key and vmnet_write_max_packets_key into our configuration to optimize packet transmission? Are those values populated dynamically or manually if so any recommended value ranges ? Buffer Allocation Issue: What strategies can we employ to mitigate this buffer allocation error and ensure more reliable packet transmission? We occasionally encounter the following error during packet writes: Error Domain=NSCocoaErrorDomain Code=512 "The file couldn’t be saved." Error Domain=NSPOSIXErrorDomain Code=55 "No buffer space available" Your insights on these matters would be greatly appreciated.