Re: [PATCH net-next v4 1/2] net/rds: restrict the rdma_cm ids to IB devices

[sashiko-bot@kernel.org]

> RDS only has an IB transport, but it never tells the rdma_cm so.  The
> listener created in rds_rdma_listen_init() is therefore installed on
> every RDMA device in the system, including iWARP RNICs, and the id an
> outgoing connection resolves through in rds_ib_conn_path_connect()
> may be bound to whichever device the address resolution picks:
> rds_ib_laddr_check() only vouched for the local address being served
> by one of RDS's IB devices, while cma_acquire_dev_by_src_ip() walks
> every RDMA device for the same address, so a software iWARP device
> attached to the same netdev can win.  The event handler then runs
> the IB transport's callbacks against a device that is not one.
> 
> The rdma_cm has an API for exactly this since commit a760e80e90f5
> ("RDMA/core: introduce rdma_restrict_node_type()").  Restrict all
> three ids RDS creates - the listener, the per-connection id and the
> probe id in rds_ib_laddr_check_cm() - to RDMA_NODE_IB_CA before they
> [ ... ]
> removed and left the ids unrestricted, hence the Fixes tag.
> 
> Fixes: dcdede0406d3 ("RDS: Drop stale iWARP RDMA transport")
> Assisted-by: Claude-Code:claude-fable-5
> Signed-off-by: Allison Henderson <achender@kernel.org>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260927063058.170273-1-achender@kernel.org?part=1