The
null block
driver (null_blk)
is a small driver that is mostly useful for benchmarking block-layer
implementations. It accepts all requests and marks them complete as quickly as
possible, doing as little work as possible. In June 2026, Andreas Hindborg shared
[
a patch set](https://lwn.net/ml/all/20260609-rnull-v6-19-rc5-send-v2-0-82c7404542e2@kernel.org/) implementing the same functionality in Rust, in order to show
that a simple block driver is now possible to write using the kernel's Rust APIs and to enable comparisons between the C and Rust implementations. A minimal version of the "rnull" driver is already present in the mainline kernel, but Hindborg's patch set brings it up to feature parity with the C version.
source & further reading
lwn.net — original article
Run several Linux kernels at the same time on bare metal, without a hypervisor
[$] Considering the OpenMDW license
Go 1.27 released