[PATCH net] net: mana: Remove redundant netdev_lock_ops_to_full() calls

[PATCH net] net: mana: Remove redundant netdev_lock_ops_to_full() calls

[Saurabh Sengar]

NET_SHAPER is always selected for MANA driver. When NET_SHAPER is enabled,
netdev_lock_ops_to_full() reduces effectively to only an assert for lock,
which is always held in the path when NET_SHAPER is enabled.

Remove the redundant netdev_lock_ops_to_full() call.

Fixes: d5c8f0e4e0cb ("net: mana: Fix potential deadlocks in mana napi ops")
Cc: stable@vger.kernel.org
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
---
 drivers/net/ethernet/microsoft/mana/mana_en.c | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 550843e2164b..f0dbf4e82e0b 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -2100,10 +2100,8 @@ static void mana_destroy_txq(struct mana_port_context *apc)
 		napi = &apc->tx_qp[i].tx_cq.napi;
 		if (apc->tx_qp[i].txq.napi_initialized) {
 			napi_synchronize(napi);
-			netdev_lock_ops_to_full(napi->dev);
 			napi_disable_locked(napi);
 			netif_napi_del_locked(napi);
-			netdev_unlock_full_to_ops(napi->dev);
 			apc->tx_qp[i].txq.napi_initialized = false;
 		}
 		mana_destroy_wq_obj(apc, GDMA_SQ, apc->tx_qp[i].tx_object);
@@ -2256,10 +2254,8 @@ static int mana_create_txq(struct mana_port_context *apc,
 		mana_create_txq_debugfs(apc, i);
 
 		set_bit(NAPI_STATE_NO_BUSY_POLL, &cq->napi.state);
-		netdev_lock_ops_to_full(net);
 		netif_napi_add_locked(net, &cq->napi, mana_poll);
 		napi_enable_locked(&cq->napi);
-		netdev_unlock_full_to_ops(net);
 		txq->napi_initialized = true;
 
 		mana_gd_ring_cq(cq->gdma_cq, SET_ARM_BIT);
@@ -2295,10 +2291,8 @@ static void mana_destroy_rxq(struct mana_port_context *apc,
 	if (napi_initialized) {
 		napi_synchronize(napi);
 
-		netdev_lock_ops_to_full(napi->dev);
 		napi_disable_locked(napi);
 		netif_napi_del_locked(napi);
-		netdev_unlock_full_to_ops(napi->dev);
 	}
 	xdp_rxq_info_unreg(&rxq->xdp_rxq);
 
@@ -2549,18 +2543,14 @@ static struct mana_rxq *mana_create_rxq(struct mana_port_context *apc,
 
 	gc->cq_table[cq->gdma_id] = cq->gdma_cq;
 
-	netdev_lock_ops_to_full(ndev);
 	netif_napi_add_weight_locked(ndev, &cq->napi, mana_poll, 1);
-	netdev_unlock_full_to_ops(ndev);
 
 	WARN_ON(xdp_rxq_info_reg(&rxq->xdp_rxq, ndev, rxq_idx,
 				 cq->napi.napi_id));
 	WARN_ON(xdp_rxq_info_reg_mem_model(&rxq->xdp_rxq, MEM_TYPE_PAGE_POOL,
 					   rxq->page_pool));
 
-	netdev_lock_ops_to_full(ndev);
 	napi_enable_locked(&cq->napi);
-	netdev_unlock_full_to_ops(ndev);
 
 	mana_gd_ring_cq(cq->gdma_cq, SET_ARM_BIT);
 out:
-- 
2.43.0

Re: [PATCH net] net: mana: Remove redundant netdev_lock_ops_to_full() calls

[Jakub Kicinski]

On Mon, 25 Aug 2025 04:03:14 -0700 Saurabh Sengar wrote:
> NET_SHAPER is always selected for MANA driver. When NET_SHAPER is enabled,
> netdev_lock_ops_to_full() reduces effectively to only an assert for lock,
> which is always held in the path when NET_SHAPER is enabled.
> 
> Remove the redundant netdev_lock_ops_to_full() call.
> 
> Fixes: d5c8f0e4e0cb ("net: mana: Fix potential deadlocks in mana napi ops")
> Cc: stable@vger.kernel.org

If the call is a nop why is this a stable-worthy fix?
-- 
pw-bot: cr

Re: [PATCH net] net: mana: Remove redundant netdev_lock_ops_to_full() calls

[Saurabh Singh Sengar]

On Mon, Aug 25, 2025 at 05:41:33PM -0700, Jakub Kicinski wrote:
> On Mon, 25 Aug 2025 04:03:14 -0700 Saurabh Sengar wrote:
> > NET_SHAPER is always selected for MANA driver. When NET_SHAPER is enabled,
> > netdev_lock_ops_to_full() reduces effectively to only an assert for lock,
> > which is always held in the path when NET_SHAPER is enabled.
> > 
> > Remove the redundant netdev_lock_ops_to_full() call.
> > 
> > Fixes: d5c8f0e4e0cb ("net: mana: Fix potential deadlocks in mana napi ops")
> > Cc: stable@vger.kernel.org
> 
> If the call is a nop why is this a stable-worthy fix?

I am fine removing CC and fixes tag.
I can send a V2 for it.


- Saurabh