Wasm doesn't necessarily help if it's performance-critical because that comes with its own overhead. And the kernel component of ksmbd interacts with other part

Wasm doesn't necessarily help if it's performance-critical because that comes with its own overhead. And the kernel component of ksmbd interacts with other parts of the kernel such as the vfs, sockets/rdma. If you had marshal all the objects into something safe before exposing them to a wasm sandbox (e.g. replacing pointers with some map keys) that'd increase the overhead further.