Embedding net_device into structures prohibits the usage of flexible
arrays in the net_device structure. For more details, see the discussion
at [1].

Un-embed the net_device from struct hfi1_netdev_rx by converting it
into a pointer. Then use the leverage alloc_netdev() to allocate the
net_device object at hfi1_alloc_rx().

[1] https://lore.kernel.org/all/20240229225910.79e224cf@kernel.org/

Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
---
Changelog

v5:
       	* Basically replaced the old alloc_netdev() by the new helper
          alloc_netdev_dummy().
v4:
       	* Fix the changelog format
v3:
       	* Re-worded the comment, by removing the first paragraph.
v2:
       	* Free struct hfi1_netdev_rx allocation if alloc_netdev() fails
       	* Pass zero as the private size for alloc_netdev().
       	* Remove wrong reference for iwl in the comments
---
 drivers/infiniband/hw/hfi1/netdev.h    | 2 +-
 drivers/infiniband/hw/hfi1/netdev_rx.c | 9 +++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/netdev.h b/drivers/infiniband/hw/hfi1/netdev.h
index 8aa074670a9c..07c8f77c9181 100644
--- a/drivers/infiniband/hw/hfi1/netdev.h
+++ b/drivers/infiniband/hw/hfi1/netdev.h
@@ -49,7 +49,7 @@ struct hfi1_netdev_rxq {
  *		When 0 receive queues will be freed.
  */
 struct hfi1_netdev_rx {
-	struct net_device rx_napi;
+	struct net_device *rx_napi;
 	struct hfi1_devdata *dd;
 	struct hfi1_netdev_rxq *rxq;
 	int num_rx_q;
diff --git a/drivers/infiniband/hw/hfi1/netdev_rx.c b/drivers/infiniband/hw/hfi1/netdev_rx.c
index 720d4c85c9c9..8608044203bb 100644
--- a/drivers/infiniband/hw/hfi1/netdev_rx.c
+++ b/drivers/infiniband/hw/hfi1/netdev_rx.c
@@ -188,7 +188,7 @@ static int hfi1_netdev_rxq_init(struct hfi1_netdev_rx *rx)
 	int i;
 	int rc;
 	struct hfi1_devdata *dd = rx->dd;
-	struct net_device *dev = &rx->rx_napi;
+	struct net_device *dev = rx->rx_napi;
 
 	rx->num_rx_q = dd->num_netdev_contexts;
 	rx->rxq = kcalloc_node(rx->num_rx_q, sizeof(*rx->rxq),
@@ -360,7 +360,11 @@ int hfi1_alloc_rx(struct hfi1_devdata *dd)
 	if (!rx)
 		return -ENOMEM;
 	rx->dd = dd;
-	init_dummy_netdev(&rx->rx_napi);
+	rx->rx_napi = alloc_netdev_dummy(0);
+	if (!rx->rx_napi) {
+		kfree(rx);
+		return -ENOMEM;
+	}
 
 	xa_init(&rx->dev_tbl);
 	atomic_set(&rx->enabled, 0);
@@ -374,6 +378,7 @@ void hfi1_free_rx(struct hfi1_devdata *dd)
 {
 	if (dd->netdev_rx) {
 		dd_dev_info(dd, "hfi1 rx freed\n");
+		free_netdev(dd->netdev_rx->rx_napi);
 		kfree(dd->netdev_rx);
 		dd->netdev_rx = NULL;
 	}
-- 
2.43.0

On Tue, Apr 30, 2024 at 09:22:11AM -0700, Breno Leitao wrote:
> Embedding net_device into structures prohibits the usage of flexible
> arrays in the net_device structure. For more details, see the discussion
> at [1].
> 
> Un-embed the net_device from struct hfi1_netdev_rx by converting it
> into a pointer. Then use the leverage alloc_netdev() to allocate the
> net_device object at hfi1_alloc_rx().
> 
> [1] https://lore.kernel.org/all/20240229225910.79e224cf@kernel.org/
> 
> Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
> Signed-off-by: Breno Leitao <leitao@debian.org>
> ---
> Changelog
> 
> v5:
>        	* Basically replaced the old alloc_netdev() by the new helper
>           alloc_netdev_dummy().
> v4:
>        	* Fix the changelog format
> v3:
>        	* Re-worded the comment, by removing the first paragraph.
> v2:
>        	* Free struct hfi1_netdev_rx allocation if alloc_netdev() fails
>        	* Pass zero as the private size for alloc_netdev().
>        	* Remove wrong reference for iwl in the comments
> ---
>  drivers/infiniband/hw/hfi1/netdev.h    | 2 +-
>  drivers/infiniband/hw/hfi1/netdev_rx.c | 9 +++++++--
>  2 files changed, 8 insertions(+), 3 deletions(-)
> 

Thanks,
Acked-by: Leon Romanovsky <leon@kernel.org>