Internships/ProjectIdeas/VsockSiblingCommunication: Difference between revisions
(Created page with "=== Sibling VM communication in vhost-user-vsock === '''Summary:''' Extend the existing vhost-user-vsock Rust application to support sibling VM communication During GSoC 2021, we developed vhost-user-vsock application in Rust. It leveraged the vhost-user protocol to emulate a virtio-vsock device in an external process. It provides the hybrid VSOCK interface over AF_UNIX introduced by Firecracker. The current implementation supports a single virtual machine (VM) per pr...") |
|||
| Line 14: | Line 14: | ||
available in the rust-vmm/vhost-device workspace to support multiple VMs | available in the rust-vmm/vhost-device workspace to support multiple VMs | ||
per instance and allow communication between sibling VMs. | per instance and allow communication between sibling VMs. | ||
vsock is usually used as a communication channel between the host and | |||
the guest running in a VM. Recently it has been proposed to extend | |||
vsock to also allow communication between VMs running on the same host | |||
(sibling VMs). | |||
Usually <code>struct sockaddr_vm { .svm_cid = 42, .svm_port = 1234 }</code> | |||
address inside a VM is used to communicate with a nested VM, but a new flag | |||
is recently added to allow sibling VM communication. | |||
So by setting <code>.svm_flags = VMADDR_FLAG_TO_HOST</code>, the connection | |||
will be forwarded to the host, allowing communication with the sibling | |||
VM that has CID 42 (if the device supports it). | |||
AF_VSOCK in Linux already supports it, but the vhost-user-vsock application | |||
still does not support it, so we want to extend it. | |||
This project will allow you to learn more about the virtio-vsock | This project will allow you to learn more about the virtio-vsock | ||
| Line 20: | Line 35: | ||
This work will be done in Rust, but we may need to patch the | This work will be done in Rust, but we may need to patch the | ||
virtio-vsock driver or | virtio-vsock driver or the AF_VSOCK core in Linux if we will find some issues. | ||
Goals: | Goals: | ||
* Understand how a virtio-vsock device works | * Understand how a virtio-vsock device works | ||
* Refactor vhost-user-vsock code to allow multiple virtio-vsock device instances | * Refactor vhost-user-vsock code to allow multiple virtio-vsock device instances | ||
* Extend the vhost-user-vsock CLI | * Extend the vhost-user-vsock CLI to define sibling VMs | ||
* Implement sibling VM communication | * Implement sibling VM communication | ||
* (optional) Support adding new VMs at runtime | * (optional) Support adding new VMs at runtime | ||
Revision as of 17:35, 17 February 2023
Sibling VM communication in vhost-user-vsock
Summary: Extend the existing vhost-user-vsock Rust application to support sibling VM communication
During GSoC 2021, we developed vhost-user-vsock application in Rust. It leveraged the vhost-user protocol to emulate a virtio-vsock device in an external process. It provides the hybrid VSOCK interface over AF_UNIX introduced by Firecracker.
The current implementation supports a single virtual machine (VM) per process instance. The idea of this project is to extend the vhost-user-vsock crate available in the rust-vmm/vhost-device workspace to support multiple VMs per instance and allow communication between sibling VMs.
vsock is usually used as a communication channel between the host and the guest running in a VM. Recently it has been proposed to extend vsock to also allow communication between VMs running on the same host (sibling VMs).
Usually struct sockaddr_vm { .svm_cid = 42, .svm_port = 1234 }
address inside a VM is used to communicate with a nested VM, but a new flag
is recently added to allow sibling VM communication.
So by setting .svm_flags = VMADDR_FLAG_TO_HOST, the connection
will be forwarded to the host, allowing communication with the sibling
VM that has CID 42 (if the device supports it).
AF_VSOCK in Linux already supports it, but the vhost-user-vsock application still does not support it, so we want to extend it.
This project will allow you to learn more about the virtio-vsock specification, rust-vmm crates, and vhost-user protocol to interface with QEMU.
This work will be done in Rust, but we may need to patch the virtio-vsock driver or the AF_VSOCK core in Linux if we will find some issues.
Goals:
- Understand how a virtio-vsock device works
- Refactor vhost-user-vsock code to allow multiple virtio-vsock device instances
- Extend the vhost-user-vsock CLI to define sibling VMs
- Implement sibling VM communication
- (optional) Support adding new VMs at runtime
Links:
- vsock info and issues
- virtio-vsock QEMU wiki page
- vhost-user-vsock application
- vhost-user-vsock project @ GSoC 2021
- Firecracker's hybrid VSOCK
- vhost-user protocol
- VMADDR_FLAG_TO_HOST flag support in Linux
Details:
- Project size: 350 hours
- Skill level: intermediate (knowledge of Rust and virtualization)
- Language: Rust
- Mentor: Stefano Garzarella <sgarzare@redhat.com>
- IRC: sgarzare / Matrix: @sgarzare:matrix.org
- Suggested by: Stefano Garzarella <sgarzare@redhat.com>