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Date:   Wed, 15 Mar 2023 14:28:41 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Eric Dumazet <edumazet@google.com>
Cc:     "David S . Miller" <davem@davemloft.net>,
        Paolo Abeni <pabeni@redhat.com>,
        David Ahern <dsahern@kernel.org>, netdev@vger.kernel.org,
        eric.dumazet@gmail.com,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH net-next 1/8] inet: preserve const qualifier in
 inet_sk()
Message-ID: <20230315142841.3a2ac99a@kernel.org>
In-Reply-To: <20230315154245.3405750-2-edumazet@google.com>
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        <20230315154245.3405750-2-edumazet@google.com>
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On Wed, 15 Mar 2023 15:42:38 +0000 Eric Dumazet wrote:
> -static inline struct inet_sock *inet_sk(const struct sock *sk)
> -{
> -	return (struct inet_sock *)sk;
> -}
> +#define inet_sk(sk) \
> +       _Generic(sk,                                          		\
> +                const struct sock * : ((const struct inet_sock *)(sk)),	\
> +                struct sock * : ((struct inet_sock *)(sk))		\
> +       )

Could we possibly use container_of_const() or define a new common
macro for this downcast? I'm worried it will spread and it's a bit
verbose.

(I think Greg is constifying things too so let me add him and Linus.)