vrf: use dev_replace_track() for better tracking

vrf_rt6_release() and vrf_rtable_release() changes dst->dev

Instead of

dev_hold(ndev);
dev_put(odev);

We should use

dev_replace_track(odev, ndev, &dst->dev_tracker, GFP_KERNEL);

If we do not transfer dst->dev_tracker to the new device,
we will get warnings from ref_tracker_dir_exit() when odev
is finally dismantled.

Fixes: 9038c320001d ("net: dst: add net device refcount tracking to dst_entry")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20211207055603.1926372-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 131c745..dbfa124 100644 (file)
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -814,9 +814,9 @@ static void vrf_rt6_release(struct net_device *dev, struct net_vrf *vrf)
         */
        if (rt6) {
                dst = &rt6->dst;
-               dev_put(dst->dev);
+               dev_replace_track(dst->dev, net->loopback_dev,
+                                 &dst->dev_tracker, GFP_KERNEL);
                dst->dev = net->loopback_dev;
-               dev_hold(dst->dev);
                dst_release(dst);
        }
 }
@@ -1061,9 +1061,9 @@ static void vrf_rtable_release(struct net_device *dev, struct net_vrf *vrf)
         */
        if (rth) {
                dst = &rth->dst;
-               dev_put(dst->dev);
+               dev_replace_track(dst->dev, net->loopback_dev,
+                                 &dst->dev_tracker, GFP_KERNEL);
                dst->dev = net->loopback_dev;
-               dev_hold(dst->dev);
                dst_release(dst);
        }
 }