[PATCH net] net: spacemit: Hold RTNL lock in emac_resume() and emac_suspend()

[Ali Tariq]

On 11/6/26 2:43 PM, Troy Mitchell wrote:
> On Thu,  5 Nov 2026 17:34:37 +0500, Ali Tariq wrote:
>> @@ -2056,7 +2059,9 @@ static int emac_suspend(struct device *dev)
>>   		return 0;
>>   	}
>>   
>> +	rtnl_lock();
>>   	emac_stop(ndev);
>> +	rtnl_unlock();
>>   
>>   	clk_disable_unprepare(priv->bus_clk);
>>   	netif_device_detach(ndev);
> This can deadlock. emac_stop() -> emac_down() calls
> cancel_work_sync(&priv->tx_timeout_task) with RTNL now held, while
> emac_tx_timeout_task() starts with rtnl_lock().
> 

Thanks Troy, that makes sense.

For the deadlock, I think the correct function to call is rtnl_trylock() 
inside the emac_tx_timeout_task(), which would return if the lock is 
already held and will hold the lock if it is not.

What are your thoughts on this? Does a v2 changing rtnl_lock() to 
rtnl_trylock() inside emac_tx_timeout_task() make sense?

Regards,
Ali