Subject: Re: [PATCH net-next v2] net: mana: Implement get_ringparam/set_ringparam for mana

From: Jakub Kicinski <[email-masked]>
Date: Wed, 31 Jul 2024 17:15:18 -0700

On Tue, 30 Jul 2024 10:01:35 -0700 Shradha Gupta wrote:
> +	err1 = mana_detach(ndev, false);
> +	if (err1) {
> +		netdev_err(ndev, "mana_detach failed: %d\n", err1);
> +		return err1;
> +	}
> +
> +	apc->tx_queue_size = new_tx;
> +	apc->rx_queue_size = new_rx;
> +	err1 = mana_attach(ndev);
> +	if (!err1)
> +		return 0;
> +
> +	netdev_err(ndev, "mana_attach failed: %d\n", err1);
> +
> +	/* Try rolling back to the older values */
> +	apc->tx_queue_size = old_tx;
> +	apc->rx_queue_size = old_rx;
> +	err2 = mana_attach(ndev);

If system is under memory pressure there's no guarantee you'll get 
the memory back, even if you revert to the old counts.
We strongly recommend you refactor the code to hold onto the old memory
until you're sure new config works.
-- 
pw-bot: cr