

Except you’re wrong about them wanting to put Rust code in the DMA subtree. As per the article linked below by M1ch431:
In a message to the Linux kernel mailing list, Hellwig wrote: “No Rust code in kernel/dma, please.” For what it’s worth, the patch added code to the rust/kernel portion of the Linux source tree, not kernel/dma, as far as we can tell.
All they were doing is adding an abstraction layer, within the already existing Rust code, so that rust drivers could communicate with the C DMA code in a uniform and predictable manner. It would have put far more work on maintainers, both C and Rust alike, to have each and every driver implement its own abstraction to the DMA API. Issues would have been/will be filed against the kernel/dma subtree in error due to issues with these myriad abstraction layers.
Yeah, same here in Australia.