Re: linux-next: manual merge of the net-next tree with the net tree

[Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx>]

Hi Stephen,

On 07/02/2023 23:46, Stephen Rothwell wrote:
> Hi all,
> 
> Today's linux-next merge of the net-next tree got a conflict in:
> 
>   net/devlink/leftover.c (net/core/devlink.c in the net tree)
> 
> between commit:
> 
>   565b4824c39f ("devlink: change port event netdev notifier from per-net to global")
> 
> from the net tree and commits:
> 
>   f05bd8ebeb69 ("devlink: move code to a dedicated directory")
>   687125b5799c ("devlink: split out core code")
> 
> from the net-next tree.
> 
> I fixed it up (I used the latter version of this file and applied the
> following merge fix up) and can carry the fix as necessary.

Thank you for the fix!

I also had the same conflicts on MPTCP side when merging mptcp-next with
-net and I used the same resolution:

Tested-by: Matthieu Baerts <matthieu.baerts@xxxxxxxxxxxx>

I was just a bit confused because I didn't see the modifications in
net/devlink/leftover.c -- devlink_port_netdevice_event() function -- in
the patch you attached but I saw them on linux-next. I guess that's
because you used the latter version of this file.

Just in case it would help the net maintainers, I attached to this email
the modification I had on my side which looks the same as Jiri's
original patch but using the new paths.

Cheers,
Matt
-- 
Tessares | Belgium | Hybrid Access Solutions
www.tessares.net

diff --git a/net/devlink/core.c b/net/devlink/core.c
index aeffd1b8206d..a4f47dafb864 100644
--- a/net/devlink/core.c
+++ b/net/devlink/core.c
@@ -205,7 +205,7 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
 		goto err_xa_alloc;
 
 	devlink->netdevice_nb.notifier_call = devlink_port_netdevice_event;
-	ret = register_netdevice_notifier_net(net, &devlink->netdevice_nb);
+	ret = register_netdevice_notifier(&devlink->netdevice_nb);
 	if (ret)
 		goto err_register_netdevice_notifier;
 
@@ -266,8 +266,7 @@ void devlink_free(struct devlink *devlink)
 	xa_destroy(&devlink->snapshot_ids);
 	xa_destroy(&devlink->ports);
 
-	WARN_ON_ONCE(unregister_netdevice_notifier_net(devlink_net(devlink),
-						       &devlink->netdevice_nb));
+	WARN_ON_ONCE(unregister_netdevice_notifier(&devlink->netdevice_nb));
 
 	xa_erase(&devlinks, devlink->index);
 
diff --git a/net/devlink/leftover.c b/net/devlink/leftover.c
index 9d6373603340..f05ab093d231 100644
--- a/net/devlink/leftover.c
+++ b/net/devlink/leftover.c
@@ -8430,6 +8430,8 @@ int devlink_port_netdevice_event(struct notifier_block *nb,
 		break;
 	case NETDEV_REGISTER:
 	case NETDEV_CHANGENAME:
+		if (devlink_net(devlink) != dev_net(netdev))
+			return NOTIFY_OK;
 		/* Set the netdev on top of previously set type. Note this
 		 * event happens also during net namespace change so here
 		 * we take into account netdev pointer appearing in this
@@ -8439,6 +8441,8 @@ int devlink_port_netdevice_event(struct notifier_block *nb,
 					netdev);
 		break;
 	case NETDEV_UNREGISTER:
+		if (devlink_net(devlink) != dev_net(netdev))
+			return NOTIFY_OK;
 		/* Clear netdev pointer, but not the type. This event happens
 		 * also during net namespace change so we need to clear
 		 * pointer to netdev that is going to another net namespace.