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Date:   Wed, 30 Mar 2022 22:44:50 +0800
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Subject: Re: [PATCH 2/4] ipmi: Limit the number of message a user may have
 outstanding
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To:     minyard@acm.org
Cc:     openipmi-developer@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, Corey Minyard <cminyard@mvista.com>
References: <20220329183340.471474-1-minyard@acm.org>
 <20220329183340.471474-3-minyard@acm.org>
From:   chenchacha <chen.chenchacha@foxmail.com>
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> @@ -2298,6 +2309,14 @@ static int i_ipmi_request(struct ipmi_user     *user,
>   	struct ipmi_recv_msg *recv_msg;
>   	int rv = 0;
>   
> +	if (user) {
> +		if (atomic_add_return(1, &user->nr_msgs) > max_msgs_per_user) {
> +			atomic_dec(&user->nr_msgs);
> +			rv = -EBUSY;
> +			goto out;
> +		}
> +	}
> +
> @@ -2369,6 +2388,8 @@ static int i_ipmi_request(struct ipmi_user     *user,
>   	rcu_read_unlock();
>   
>   out:
> +	if (rv && user)
> +		atomic_dec(&user->nr_msgs);
>   	return rv;
>   }

If the number of msg is greater than the limit, the nr_msgs will be 
decrease twice.

Should it be returned directory?

--
Chen Guanqiao