Hi Jakub,

On Wed, Nov 26, 2025 at 08:05:41PM -0800, Jakub Kicinski wrote:

On Sun, 23 Nov 2025 10:08:18 -0800 Dipayaan Roy wrote:

quoted

Implement .ndo_tx_timeout for MANA so any stalled TX queue can be detected
and a device-controlled port reset for all queues can be scheduled to a
ordered workqueue. The reset for all queues on stall detection is
recomended by hardware team.

The change introduces a single ordered workqueue
"mana_per_port_queue_reset_wq" queuing one work_struct per port,
using WQ_UNBOUND | WQ_MEM_RECLAIM so stalled queue reset work can
run on any CPU and still make forward progress under memory
pressure.

And we need to be able to reset the NIC queue under memory pressure
because.. ?  I could be wrong but I still find this unusual / defensive
programming, if you could point me at some existing drivers that'd help.

I found these existing drivers using 'create_singlethread_workqueue',

drivers/net/ethernet/mellanox/mlx4/en_main.c
drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
drivers/net/ethernet/mellanox/mlx5/core/en_main.c

'create_singlethread_workqueue' in turn uses  WQ_MEM_RECLAIM

as in below macros 
#define alloc_ordered_workqueue(fmt, flags, args...) \
	alloc_workqueue(fmt, WQ_UNBOUND | __WQ_ORDERED | (flags), 1,
##args)

...
#define create_singlethread_workqueue(name) \
	alloc_ordered_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM,
name)

I will switch to directly using create_singlethread_workqueue instead
of explicitly mentioning the flags in the next version. 

 

quoted

@@ -3287,6 +3341,7 @@ static int mana_probe_port(struct mana_context *ac, int port_idx,
 	ndev->min_mtu = ETH_MIN_MTU;
 	ndev->needed_headroom = MANA_HEADROOM;
 	ndev->dev_port = port_idx;
+	ndev->watchdog_timeo = 15 * HZ;

5 sec is typical, off the top of my head

As per our internal discussion, 15 second timeout recommended by HW team based on the FPGA reconfig
scenario.

quoted

@@ -3647,6 +3717,11 @@ void mana_remove(struct gdma_dev *gd, bool suspending)
 		free_netdev(ndev);
 	}
 
+	if (ac->per_port_queue_reset_wq) {
+		destroy_workqueue(ac->per_port_queue_reset_wq);
+		ac->per_port_queue_reset_wq = NULL;
+	}

I think you're missing this cleanup in the failure path of mana_probe

Right, if all the ports fail to probe the clean up will get skipped from
mana_remove. I will fix this in the v5.

-- 
pw-bot: cr

Thank you for the comments, I will work on it in v5.

Regards