Commit ba6f418f authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

net: bubble up taking netdev instance lock to callers of net_devmem_unbind_dmabuf() 



A recent commit added taking the netdev instance lock
in netdev_nl_bind_rx_doit(), but didn't remove it in
net_devmem_unbind_dmabuf() which it calls from an error path.
Always expect the callers of net_devmem_unbind_dmabuf() to
hold the lock. This is consistent with net_devmem_bind_dmabuf().

(Not so) coincidentally this also protects mp_param with the instance
lock, which the rest of this series needs.

Fixes: 1d22d306 ("net: drop rtnl_lock for queue_mgmt operations")
Reviewed-by: default avatarMina Almasry <almasrymina@google.com>
Acked-by: default avatarStanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250324224537.248800-2-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 51068769

net/core/devmem.c

+0 −2
Original line number Diff line number Diff line
@@ -128,12 +128,10 @@ void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) 
		rxq->mp_params.mp_priv = NULL;

		rxq->mp_params.mp_ops = NULL;



		netdev_lock(binding->dev);

		rxq_idx = get_netdev_rx_queue_index(rxq);



		err = netdev_rx_queue_restart(binding->dev, rxq_idx);

		WARN_ON(err && err != -ENETDOWN);

		netdev_unlock(binding->dev);

	}



	xa_erase(&net_devmem_dmabuf_bindings, binding->id);

net/core/netdev-genl.c

+2 −0
Original line number Diff line number Diff line
@@ -947,7 +947,9 @@ void netdev_nl_sock_priv_destroy(struct netdev_nl_sock *priv) 


	mutex_lock(&priv->lock);

	list_for_each_entry_safe(binding, temp, &priv->bindings, list) {

		netdev_lock(binding->dev);

		net_devmem_unbind_dmabuf(binding);

		netdev_unlock(binding->dev);

	}

	mutex_unlock(&priv->lock);

}