Re: [PATCH 1/3] arch/um/drivers: remove duplicate structure field initialization

[Stephen Hemminger <shemminger@vyatta.com>]

On Mon, 21 Jun 2010 15:53:49 -0700
Andrew Morton <akpm@linux-foundation.org> wrote:

> On Sun, 20 Jun 2010 15:40:02 +0200 (CEST)
> Julia Lawall <julia@diku.dk> wrote:
> 
> > From: Julia Lawall <julia@diku.dk>
> > 
> > There are two initializations of ndo_set_mac_address, one to a local
> > function that is not used otherwise and one to a function that is defined
> > elsewhere.  This patch keeps the initialization to the local function.
> > 
> > The semantic match that finds this problem is as follows:
> > (http://coccinelle.lip6.fr/)
> > 
> > // <smpl>
> > @r@
> > identifier I, s, fld;
> > position p0,p;
> > expression E;
> > @@
> > 
> > struct I s =@p0 { ... .fld@p = E, ...};
> > 
> > @s@
> > identifier I, s, r.fld;
> > position r.p0,p;
> > expression E;
> > @@
> > 
> > struct I s =@p0 { ... .fld@p = E, ...};
> > 
> > @script:python@
> > p0 << r.p0;
> > fld << r.fld;
> > ps << s.p;
> > pr << r.p;
> > @@
> > 
> > if int(ps[0].line)<int(pr[0].line) or int(ps[0].column)<int(pr[0].column):
> >   cocci.print_main(fld,p0)
> > // </smpl>
> > 
> > Signed-off-by: Julia Lawall <julia@diku.dk>
> > 
> > ---
> > This fix was sent previously, in September 2009.
> > 
> >  arch/um/drivers/net_kern.c |    1 -
> >  1 file changed, 1 deletion(-)
> > 
> > diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
> > index f053726..d2d42d8 100644
> > --- a/arch/um/drivers/net_kern.c
> > +++ b/arch/um/drivers/net_kern.c
> > @@ -380,7 +380,6 @@ static const struct net_device_ops uml_netdev_ops = {
> >  	.ndo_tx_timeout 	= uml_net_tx_timeout,
> >  	.ndo_set_mac_address	= uml_net_set_mac,
> >  	.ndo_change_mtu 	= uml_net_change_mtu,
> > -	.ndo_set_mac_address 	= eth_mac_addr,
> >  	.ndo_validate_addr	= eth_validate_addr,
> >  };
> 
> Your patch is actually a functional change.
> 
> Geeze, whatamess.
> 
> 
> This duplicated field was added by
> 
> : commit 8bb95b39a16ed55226810596f92216c53329d2fe
> : Author:     Stephen Hemminger <shemminger@linux-foundation.org>
> : AuthorDate: Thu Mar 26 15:11:17 2009 +0000
> : Commit:     David S. Miller <davem@davemloft.net>
> : CommitDate: Fri Mar 27 00:46:40 2009 -0700
> :
> :    uml: convert network device to netdevice ops
> 
> Either Stephen fat-fingered it, or it was a secret, unchangelogged (and
> partial) cleanup.
> 
> Presumably the spin_lock_irq(&lp->lock); stuff is in uml_net_set_mac()
> for a reason so presumably we should restore it.
> 
> 
> - Use the standard eth_mac_addr() in uml_net_set_mac()
> 
> - Remove unneeded and racy local set_ether_mac()
> 
> - Remove duplicated (and incorrect)
>   uml_netdev_ops.ndo_set_mac_address initializer.
> 
> Fixes 8bb95b39a16ed55226810596f92216c53329d2fe ("uml: convert network
> device to netdevice ops").
> 
> diff -puN arch/um/drivers/net_kern.c~arch-um-drivers-remove-duplicate-structure-field-initialization arch/um/drivers/net_kern.c
> --- a/arch/um/drivers/net_kern.c~arch-um-drivers-remove-duplicate-structure-field-initialization
> +++ a/arch/um/drivers/net_kern.c
> @@ -25,11 +25,6 @@
>  #include "net_kern.h"
>  #include "net_user.h"
>  
> -static inline void set_ether_mac(struct net_device *dev, unsigned char *addr)
> -{
> -	memcpy(dev->dev_addr, addr, ETH_ALEN);
> -}
> -
>  #define DRIVER_NAME "uml-netdev"
>  
>  static DEFINE_SPINLOCK(opened_lock);
> @@ -266,7 +261,7 @@ static int uml_net_set_mac(struct net_de
>  	struct sockaddr *hwaddr = addr;
>  
>  	spin_lock_irq(&lp->lock);
> -	set_ether_mac(dev, hwaddr->sa_data);
> +	eth_mac_addr(dev, hwaddr->sa_data);
>  	spin_unlock_irq(&lp->lock);
>  
>  	return 0;
> @@ -380,7 +375,6 @@ static const struct net_device_ops uml_n
>  	.ndo_tx_timeout 	= uml_net_tx_timeout,
>  	.ndo_set_mac_address	= uml_net_set_mac,
>  	.ndo_change_mtu 	= uml_net_change_mtu,
> -	.ndo_set_mac_address 	= eth_mac_addr,
>  	.ndo_validate_addr	= eth_validate_addr,
>  };
>  
> @@ -478,7 +472,7 @@ static void eth_configure(int n, void *i
>  	    ((*transport->user->init)(&lp->user, dev) != 0))
>  		goto out_unregister;
>  
> -	set_ether_mac(dev, device->mac);
> +	eth_mac_addr(dev, device->mac);
>  	dev->mtu = transport->user->mtu;
>  	dev->netdev_ops = &uml_netdev_ops;
>  	dev->ethtool_ops = &uml_net_ethtool_ops;

Looks correct thanks.