[PATCH net-next v4 2/2] net: mana: Drop TX skb on post_work_request failure and unmap resources

Aditya Garg
2025-11-12T13:11:48Z

Drop TX packets when posting the work request fails and ensure DMA
mappings are always cleaned up.

Signed-off-by: Aditya Garg <gargaditya@linux.microsoft.com>
---
Changes in v4:
* Fix warning during build reported by kernel test robot
---
drivers/net/ethernet/microsoft/mana/gdma_main.c | 6 +-----
drivers/net/ethernet/microsoft/mana/mana_en.c | 7 +++----
include/net/mana/mana.h | 1 +
3 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c
index effe0a2f207a..8fd70b34807a 100644
--- a/drivers/net/ethernet/microsoft/mana/gdma_main.c
+++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c
@@ -1300,7 +1300,6 @@ int mana_gd_post_work_request(struct gdma_queue *wq,
struct gdma_posted_wqe_info *wqe_info)
{
u32 client_oob_size = wqe_req->inline_oob_size;
- struct gdma_context *gc;
u32 sgl_data_size;
u32 max_wqe_size;
u32 wqe_size;
@@ -1330,11 +1329,8 @@ int mana_gd_post_work_request(struct gdma_queue *wq,
if (wqe_size > max_wqe_size)
return -EINVAL;

- if (wq->monitor_avl_buf && wqe_size > mana_gd_wq_avail_space(wq)) {
- gc = wq->gdma_dev->gdma_context;
- dev_err(gc->dev, "unsuccessful flow control!\n");
+ if (wq->monitor_avl_buf && wqe_size > mana_gd_wq_avail_space(wq))
return -ENOSPC;
- }

if (wqe_info)
wqe_info->wqe_size_in_bu = wqe_size / GDMA_WQE_BU_SIZE;
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 67ae5421f9ee..066d822f68f0 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -491,9 +491,9 @@ netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev)

if (err) {
(void)skb_dequeue_tail(&txq->pending_skbs);
+ mana_unmap_skb(skb, apc);
netdev_warn(ndev, "Failed to post TX OOB: %d\n", err);
- err = NETDEV_TX_BUSY;
- goto tx_busy;
+ goto free_sgl_ptr;
}

err = NETDEV_TX_OK;
@@ -513,7 +513,6 @@ netdev_tx_t mana_start_xmit(struct sk_buff *skb, struct net_device *ndev)
tx_stats->bytes += len + ((num_gso_seg - 1) * gso_hs);
u64_stats_update_end(&tx_stats->syncp);

-tx_busy:
if (netif_tx_queue_stopped(net_txq) && mana_can_tx(gdma_sq)) {
netif_tx_wake_queue(net_txq);
apc->eth_stats.wake_queue++;
@@ -1679,7 +1678,7 @@ static int mana_move_wq_tail(struct gdma_queue *wq, u32 num_units)
return 0;
}

-static void mana_unmap_skb(struct sk_buff *skb, struct mana_port_context *apc)
+void mana_unmap_skb(struct sk_buff *skb, struct mana_port_context *apc)
{
struct mana_skb_head *ash = (struct mana_skb_head *)skb->head;
struct gdma_context *gc = apc->ac->gdma_dev->gdma_context;
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 50a532fb30d6..d05457d3e1ab 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -585,6 +585,7 @@ int mana_set_bw_clamp(struct mana_port_context *apc, u32 speed,
void mana_query_phy_stats(struct mana_port_context *apc);
int mana_pre_alloc_rxbufs(struct mana_port_context *apc, int mtu, int num_queues);
void mana_pre_dealloc_rxbufs(struct mana_port_context *apc);
+void mana_unmap_skb(struct sk_buff *skb, struct mana_port_context *apc);

extern const struct ethtool_ops mana_ethtool_ops;
extern struct dentry *mana_debugfs_root;
--
2.43.0