Intel Continues Bringing Up DMA-BUF Support For RDMA

Written by Michael Larabel in Intel on 5 October 2020 at 02:54 AM EDT. 5 Comments
Presumably with Xe-HP in mind, Intel engineers continue working on adding DMA-BUF support to the Linux kernel's RDMA code.

Intel engineers are working to support DMA-BUF for peer-to-peer transactions over PCI Express between RDMA NICs and supported PCIe devices/drivers.

The peer-to-peer support with capable hardware and drivers means bypassing the system memory when the CPU doesn't need to access it, in turn offering better performance. AMD engineers have also been investing in Linux's peer-to-peer DMA capabilities as well.

Intel selected the DMA-BUF interface for the RDMA P2P focus due to already being supported by GPU drivers and they feeling it is better tailored for this purpose than the likes of Heterogeneous Memory Management, PCI P2P DMA, and alternatives.

Intel's Linux graphics driver would still need changes for making use of this P2P RDMA support but presumably it will be coming as part of Xe HP/HPC enablement. The latest RDMA DMA-BUF patches were sent out on Sunday.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via

Popular News This Week