>
> After investigation, seems the culprit is commit 647bf13ce944 ("RDMA/rxe:
> Create duplicate mapping tables for FMRs"). The problem is
> mr_check_range returns -EFAULT after find iova and length are not
> valid, so connection between two VMs can't be established.
>
> Revert the commit manually or apply below temporary change, rxe works
> again with rnbd/rtrs though I don't think it is the right thing to do.
> Could experts provide a proper solution? Thanks.
>
This patch fixed failures in blktests and srp which were discussed at length. See e.g.
https://lore.kernel.org/linux-rdma/20210907163939.GW1200268@xxxxxxxx/
and related messages. The conclusion was that two mappings were required. One owned by the
driver and one by the 'hardware', i.e. bottom half in the rxe case, allowing updating a new mapping
while the old one is still active and then switching them.
If this case has iova and length not valid as indicated is there a problem with the test case?
Bob
