On 12/27/24 5:04 AM, Guangguan Wang wrote:

The command 'smc_pnet -a -I <ethx> <pnetid>' will add <pnetid>
to the pnetid table and will attach the <pnetid> to net device
whose name is <ethx>. But When do SMCR by <ethx>, in function
smc_pnet_find_roce_by_pnetid, it will use <ethx>'s base ndev's
pnetid to match rdma device, not <ethx>'s pnetid. The asymmetric
use of the pnetid seems weird. Sometimes it is difficult to know
the hierarchy of net device what may make it difficult to configure
the pnetid and to use the pnetid. Looking into the history of
commit, it was the commit 890a2cb4a966 ("net/smc: rework pnet table")
that changes the ndev from the <ethx> to the <ethx>'s base ndev
when finding pnetid by pnetid table. It seems a mistake.

This patch changes the ndev back to the <ethx> when finding pnetid
by pnetid table.

Fixes: 890a2cb4a966 ("net/smc: rework pnet table")
Signed-off-by: Guangguan Wang <redacted>

If I read correctly, this will break existing applications using the
lookup schema introduced by the blamed commit - which is not very recent.

Perhaps for a net patch would be better to support both lookup schemas i.e.

	(smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid) ||
	 smc_pnet_find_ndev_pnetid_by_table(base_ndev, ndev_pnetid))

?

Thanks,

Paolo