Re: [PATCH v5 net-next 1/7] net: move ethtool-related netdev state into its own struct

[Jakub Kicinski <kuba@kernel.org>]

On Tue, 18 Jun 2024 16:05:13 -0700 David Wei wrote:
> > @@ -11065,6 +11065,9 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
> >  	dev->real_num_rx_queues = rxqs;
> >  	if (netif_alloc_rx_queues(dev))
> >  		goto free_all;
> > +	dev->ethtool = kzalloc(sizeof(*dev->ethtool), GFP_KERNEL_ACCOUNT);  
> 
> Why GFP_KERNEL_ACCOUNT instead of just GFP_KERNEL?

netdevs can be created by a user, think veth getting created in 
a container. So we need to account the allocated memory towards 
the memory limit of the current user.

> > +	if (!dev->ethtool)
> > +		goto free_all;
> >  
> >  	strcpy(dev->name, name);
> >  	dev->name_assign_type = name_assign_type;
> > @@ -11115,6 +11118,7 @@ void free_netdev(struct net_device *dev)
> >  		return;
> >  	}
> >  
> > +	kfree(dev->ethtool);  
> 
> dev->ethtool = NULL?

defensive programming is sometimes permitted by not encouraged :)