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Date: Wed, 6 Dec 2023 09:37:08 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Jiawen Wu <jiawenwu@trustnetic.com>
Cc: davem@davemloft.net, edumazet@google.com, pabeni@redhat.com,
 linux@armlinux.org.uk, andrew@lunn.ch, netdev@vger.kernel.org,
 mengyuanlou@net-swift.com
Subject: Re: [PATCH net-next v3 4/7] net: wangxun: add ethtool_ops for ring
 parameters
Message-ID: <20231206093708.62f91a45@kernel.org>
In-Reply-To: <20231206095355.1220086-5-jiawenwu@trustnetic.com>
References: <20231206095355.1220086-1-jiawenwu@trustnetic.com>
	<20231206095355.1220086-5-jiawenwu@trustnetic.com>
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On Wed,  6 Dec 2023 17:53:52 +0800 Jiawen Wu wrote:
> +	ngbe_down(wx);
> +
> +	err = wx_set_ring(wx, new_tx_count, new_rx_count);
> +
> +	wx_configure(wx);
> +	ngbe_up(wx);

What if it fails? We don't allow down() / up() cycles on ethtool config
changes. You have to implement some form of reconfiguration, at minimum
it needs to be resilient to memory allocation failures (in which case
the old config should be kept and the device should keep running).