RDMA/cxgb3: Fail loopback connections.
The cxgb3 HW and driver don't support loopback RDMA connections. So fail
any connection attempt where the destination address is local.
Signed-off-by: Steve Wise <[email protected]>
---
drivers/infiniband/hw/cxgb3/iwch_cm.c | 16 ++++++++++++++++
1 files changed, 16 insertions(+), 0 deletions(-)
diff --git a/drivers/infiniband/hw/cxgb3/iwch_cm.c b/drivers/infiniband/hw/cxgb3/iwch_cm.c
index e9a08fa..5d82723 100644
--- a/drivers/infiniband/hw/cxgb3/iwch_cm.c
+++ b/drivers/infiniband/hw/cxgb3/iwch_cm.c
@@ -1784,6 +1784,17 @@ err:
return err;
}
+static void is_loopback_dst(struct iw_cm_id *cm_id)
+{
+ struct net_device *dev;
+
+ dev = ip_dev_find(&init_net, cm_id->remote_addr.sin_addr.s_addr);
+ if (!dev)
+ return 0;
+ dev_put(dev);
+ return 1;
+}
+
int iwch_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
{
int err = 0;
@@ -1791,6 +1802,11 @@ int iwch_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
struct iwch_ep *ep;
struct rtable *rt;
+ if (is_loopback_dst(cm_id)) {
+ err = -ENOSYS;
+ goto out;
+ }
+
ep = alloc_ep(sizeof(*ep), GFP_KERNEL);
if (!ep) {
printk(KERN_ERR MOD "%s - cannot alloc ep.\n", __FUNCTION__);
applied, although:
> +static void is_loopback_dst(struct iw_cm_id *cm_id)
> +{
> + struct net_device *dev;
> +
> + dev = ip_dev_find(&init_net, cm_id->remote_addr.sin_addr.s_addr);
> + if (!dev)
> + return 0;
> + dev_put(dev);
> + return 1;
> +}
is there any way this could trigger when it should, like if I'm trying
to make a connection from one local device to a different local device
(which should work fine)?
- R.
Roland Dreier wrote:
> applied, although:
>
> > +static void is_loopback_dst(struct iw_cm_id *cm_id)
> > +{
> > + struct net_device *dev;
> > +
> > + dev = ip_dev_find(&init_net, cm_id->remote_addr.sin_addr.s_addr);
> > + if (!dev)
> > + return 0;
> > + dev_put(dev);
> > + return 1;
> > +}
>
> is there any way this could trigger when it should, like if I'm trying
> to make a connection from one local device to a different local device
> (which should work fine)?
>
As far as I can tell, if the app does a rdma_resolve_addr() on the dst
addr (which is a local address), then the routing lookup will find the
local interface with that dst addr, and that device will be used for the
connect. IE src and dst devices are the same.
Maybe if the app does an explicit bind to the addr on one device, then
connects to the addr on the other device. But that's not gonna work
either, I think. I still think it will resolve to one device and that
device cannot do loopback...
Steve.