On Thu, Nov 21, 2019 at 02:45:32PM +0000, Jorgen Hansen wrote: > > From: Stefano Garzarella [mailto:sgarzare@xxxxxxxxxx] > > Sent: Tuesday, November 19, 2019 12:01 PM > > This series introduces a new transport (vsock_loopback) to handle > > local communication. > > This could be useful to test vsock core itself and to allow developers > > to test their applications without launching a VM. > > > > Before this series, vmci and virtio transports allowed this behavior, > > but only in the guest. > > We are moving the loopback handling in a new transport, because it > > might be useful to provide this feature also in the host or when > > no H2G/G2H transports (hyperv, virtio, vmci) are loaded. > > > > The user can use the loopback with the new VMADDR_CID_LOCAL (that > > replaces VMADDR_CID_RESERVED) in any condition. > > Otherwise, if the G2H transport is loaded, it can also use the guest > > local CID as previously supported by vmci and virtio transports. > > If G2H transport is not loaded, the user can also use VMADDR_CID_HOST > > for local communication. > > > > Patch 1 is a cleanup to build virtio_transport_common without virtio > > Patch 2 adds the new VMADDR_CID_LOCAL, replacing > > VMADDR_CID_RESERVED > > Patch 3 adds a new feature flag to register a loopback transport > > Patch 4 adds the new vsock_loopback transport based on the loopback > > implementation of virtio_transport > > Patch 5 implements the logic to use the local transport for loopback > > communication > > Patch 6 removes the loopback from virtio_transport > > > > @Jorgen: Do you think it might be a problem to replace > > VMADDR_CID_RESERVED with VMADDR_CID_LOCAL? > > No, that should be fine. It has never allowed for use with stream sockets in > AF_VSOCK. The only potential use would be for datagram sockets, but that > side appears to be unaffected by your changes, since loopback is only > introduced for SOCK_STREAM. > Yes, datagram sockets are not affected. Thanks for the clarification, Stefano
