Re: [PATCH net-next v2] netdevice: define and allocate &net_device _properly_

From: Breno Leitao
Date: Wed Jul 10 2024 - 07:19:50 EST


Hello Eric,

On Tue, Jul 09, 2024 at 08:27:45AM -0700, Eric Dumazet wrote:
> On Tue, Jul 9, 2024 at 5:54 AM Breno Leitao <leitao@xxxxxxxxxx> wrote:

> > @@ -2596,7 +2599,7 @@ void dev_net_set(struct net_device *dev, struct net *net)
> > */
> > static inline void *netdev_priv(const struct net_device *dev)
> > {
> > - return (char *)dev + ALIGN(sizeof(struct net_device), NETDEV_ALIGN);
> > + return (void *)dev->priv;
>
> Minor remark : the cast is not needed, but this is fine.

In fact, the compiler is not very happy if I remove the cast:

./include/linux/netdevice.h:2603:9: error: returning 'const u8[]' (aka 'const unsigned char[]') from a function with result type 'void *' discards qualifiers [-Werror,-Wincompatible-pointer-types-discards-qualifiers]
2603 | return dev->priv;
| ^~~~~~~~~