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Date:   Thu, 12 Oct 2023 00:37:37 +0530
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Subject: Re: [PATCH] Remove extra unlock for the mutex
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To:     Eric Dumazet <edumazet@google.com>
Cc:     Greg KH <gregkh@linuxfoundation.org>, davem@davemloft.net,
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From:   Abhinav Singh <singhabhinav9051571833@gmail.com>
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On 10/11/23 23:13, Eric Dumazet wrote:
> 
> There is no undefined behavior, only sparse that might be confused a little.
> 
> I do not think we can express in sparse the fact that
> inet_csk_find_open_port() acquires head->lock
> 
> (head being the return value of this function...)
> 
> The following does not help.
> 
> diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
> index aeebe881668996057d1495c84eee0f0b644b7ad0..ed7b3993316cd1ba0b2859b0bd3f447e066bd3b5
> 100644
> --- a/net/ipv4/inet_connection_sock.c
> +++ b/net/ipv4/inet_connection_sock.c
> @@ -323,6 +323,7 @@ static struct inet_bind_hashbucket *
>   inet_csk_find_open_port(const struct sock *sk, struct
> inet_bind_bucket **tb_ret,
>                          struct inet_bind2_bucket **tb2_ret,
>                          struct inet_bind_hashbucket **head2_ret, int *port_ret)
> +       __acquires(head->lock)
>   {
>          struct inet_hashinfo *hinfo = tcp_or_dccp_get_hashinfo(sk);
>          int i, low, high, attempt_half, port, l3mdev;

Okay got it. Thank you for your time maintainers.And apologizes for not 
thoroughly checking before sending the patch. I have a question, there 
were some type checking warning as well from sparse tool. Can a create 
patch for fixing those type checking warning?