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Date: Tue, 29 Oct 2024 15:36:19 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Jeremy Kerr <jk@codeconstruct.com.au>
Cc: Andrew Lunn <andrew@lunn.ch>, Andrew Lunn <andrew+netdev@lunn.ch>,
 "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>, Joel Stanley
 <joel@jms.id.au>, Jacky Chou <jacky_chou@aspeedtech.com>, Jacob Keller
 <jacob.e.keller@intel.com>, netdev@vger.kernel.org
Subject: Re: [PATCH net 1/2] net: ethernet: ftgmac100: prevent use after
 free on unregister when using NCSI
Message-ID: <20241029153619.1743f07e@kernel.org>
In-Reply-To: <0123d308bb8577e7ccb5d99c504cec389ba8fe15.camel@codeconstruct.com.au>
References: <20241028-ftgmac-fixes-v1-0-b334a507be6c@codeconstruct.com.au>
	<20241028-ftgmac-fixes-v1-1-b334a507be6c@codeconstruct.com.au>
	<fe5630d4-1502-45eb-a6fb-6b5bc33506a9@lunn.ch>
	<0123d308bb8577e7ccb5d99c504cec389ba8fe15.camel@codeconstruct.com.au>
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On Tue, 29 Oct 2024 12:32:53 +0800 Jeremy Kerr wrote:
> As the ordering in ftgmac100_remove() is:
> 
> 
>         if (priv->ndev)
>                 ncsi_unregister_dev(priv->ndev);
>         unregister_netdev(netdev);
> 
> which, is (I assume intentionally) symmetric with the _probe, which
> does:
> 
>                 priv->ndev = ncsi_register_dev(netdev, ftgmac100_ncsi_handler);
> 
>         /* ... */
> 
>         register_netdev(netdev)

To be clear - symmetric means mirror image.
I agree with Andrew.