> On Jun 6, 2023, at 11:48 AM, Jason Gunthorpe <jgg@xxxxxxxxxx> wrote: > > On Fri, Jun 02, 2023 at 03:24:30PM -0400, Chuck Lever wrote: >> From: Chuck Lever <chuck.lever@xxxxxxxxxx> >> >> We would like to enable the use of siw on top of a VPN that is >> constructed and managed via a tun device. That hasn't worked up >> until now because ARPHRD_NONE devices (such as tun devices) have >> no GID for the RDMA/core to look up. >> >> But it turns out that the egress device has already been picked for >> us. addr_handler() just has to do the right thing with it. >> >> Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx> >> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> >> --- >> drivers/infiniband/core/cma.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c >> index 56e568fcd32b..3351dc5afa17 100644 >> --- a/drivers/infiniband/core/cma.c >> +++ b/drivers/infiniband/core/cma.c >> @@ -704,11 +704,15 @@ cma_validate_port(struct ib_device *device, u32 port, >> ndev = dev_get_by_index(dev_addr->net, bound_if_index); >> if (!ndev) >> return ERR_PTR(-ENODEV); >> + } else if (dev_type == ARPHRD_NONE) { >> + sgid_attr = rdma_get_gid_attr(device, port, 0); > > It seems believable, should it be locked to iwarp devices? > > More broadly, should iwarp devices just always do this and skip all > the rest of it? > > I think it also has to check that the returned netdev in the sgid_attr > matches the egress netdev selected? Both @ndev and sgid_attr.ndev are NULL here. So I assume you want the code to check, on return, that sgid_attr.device == device? -- Chuck Lever