On Tue, Feb 4, 2025 at 6:06 PM Jakub Kicinski [off-list ref] wrote:

On Tue, 4 Feb 2025 11:41:09 -0800 Stanislav Fomichev wrote:

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Don't we need some way for the device to opt-in (or opt-out) and avoid
such issues?

Yeah, I think likely the driver needs to declare support (i.e. it's
not using dma-mapping API with dma-buf addresses).

netif_skb_features/ndo_features_check seems like a good fit?

validate_xmit_skb()

I was thinking I'd check dev->features during the dmabuf tx binding
and check the binding completely if the feature is not supported. I'm
guessing another check in validate_xmit_skb() is needed anyway for
cases such as forwarding at what not?

-- 
Thanks,
Mina