RE: [PATCH net-next v3 12/13] net: warn ops-locked drivers still using ndo_set_rx_mode

-----Original Message-----
From: Stanislav Fomichev <sdf@fomichev.me>
Sent: Friday, March 20, 2026 2:25 AM
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Subject: [PATCH net-next v3 12/13] net: warn ops-locked drivers still
using ndo_set_rx_mode

Now that all in-tree ops-locked drivers have been converted to
ndo_set_rx_mode_async, add a warning in register_netdevice to catch
any remaining or newly added drivers that use ndo_set_rx_mode with ops
locking. This ensures future driver authors are guided toward the
async path.

Also route ops-locked devices through dev_rx_mode_work even if they
lack rx_mode NDOs, to ensure netdev_ops_assert_locked() does not fire
on the legacy path where only RTNL is held.

Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
---
 net/core/dev.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/net/core/dev.c b/net/core/dev.c index

fc5c9b14faa0..f38ab254708b 100644

--- a/net/core/dev.c
+++ b/net/core/dev.c

@@ -9779,7 +9779,8 @@ void __dev_set_rx_mode(struct net_device *dev)
 	if (!netif_up_and_present(dev))
 		return;

-	if (ops->ndo_set_rx_mode_async || ops->ndo_change_rx_flags) {
+	if (ops->ndo_set_rx_mode_async || ops->ndo_change_rx_flags ||
+	    netdev_need_ops_lock(dev)) {
 		queue_work(rx_mode_wq, &dev->rx_mode_work);
 		return;
 	}

@@ -11471,6 +11472,11 @@ int register_netdevice(struct net_device

*dev)
 		goto err_uninit;
 	}

+	if (netdev_need_ops_lock(dev) &&
+	    dev->netdev_ops->ndo_set_rx_mode &&
+	    !dev->netdev_ops->ndo_set_rx_mode_async)
+		netdev_WARN(dev, "ops-locked drivers should use
+ndo_set_rx_mode_async\n");
+
 	ret = netdev_do_alloc_pcpu_stats(dev);
 	if (ret)
 		goto err_uninit;
--
2.53.0