Re: [RFC net-next 1/4] net: Allow non parent devices to be used for ZC DMA

On Wed, 2 Jul 2025 20:24:23 +0300 Dragos Tatulea wrote:

For zerocopy (io_uring, devmem), there is an assumption that the
parent device can do DMA. However that is not always the case:
for example mlx5 SF devices have an auxiliary device as a parent.

Noob question -- I thought that the point of SFs was that you can pass
them thru to a VM. How do they not have DMA support? Is it added on
demand by the mediated driver or some such?