Re: [PATCH for-next V1 5/9] IB/core: Add rdma_network_type to wc

[Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>]

> +	/* Use the hint from IP Stack to select GID Type */
> +	network_gid_type = ib_network_to_gid_type(addr->dev_addr.network);
> +	if (addr->dev_addr.network != RDMA_NETWORK_IB) {
> +		route->path_rec->gid_type = network_gid_type;
> +		/* TODO: get the hoplimit from the inet/inet6 device */
> +		route->path_rec->hop_limit = IPV6_DEFAULT_HOPLIMIT;

Uh, that is more than a TODO, that is showing this is all messed up.

It isn't just the hop limit that has to come from the route entry, all
the source information of the path comes from there. Ie the gid table
should accept the route entry directly and spit out the sgid_index.

The responder side is the same, it also needs to do a route lookup to
figure out what it is doing, and that may not match what the rx says
from the headers. This is important stuff.

I really don't like the API changes that went in with the last series
that added net_dev and gid_attr everywhere, that just seems to be
enabling mistakes like the above. You can't use rocev2 without doing
route lookups, providing APIs that don't force this to happen just
encourages broken flows like this.

Jason
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