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Date:   Mon, 22 Aug 2022 16:44:43 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Hawkins Jiawei <yin31149@gmail.com>
Cc:     David Howells <dhowells@redhat.com>,
        Marc Dionne <marc.dionne@auristor.com>,
        "David S. Miller" <davem@davemloft.net>,
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Subject: Re: [PATCH] rxrpc: fix bad unlock balance in rxrpc_do_sendmsg
Message-ID: <20220822134443.GE2695@kadam>
References: <20220822112952.2961-1-yin31149@gmail.com>
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On Mon, Aug 22, 2022 at 09:04:14PM +0800, Hawkins Jiawei wrote:
>  static int rxrpc_send_data(struct rxrpc_sock *rx,
>  			   struct rxrpc_call *call,
>  			   struct msghdr *msg, size_t len,
> -			   rxrpc_notify_end_tx_t notify_end_tx)
> +			   rxrpc_notify_end_tx_t notify_end_tx,
> +			   bool *holding_mutex)
>  {
>  	struct rxrpc_skb_priv *sp;
>  	struct sk_buff *skb;
> @@ -299,6 +318,13 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
>  	bool more;
>  	int ret, copied;
>  
> +	/*
> +	 * The caller holds the call->user_mutex when calls
> +	 * rxrpc_send_data(), so initial it with True
> +	 */
> +	if (holding_mutex)
> +		*holding_mutex = true;

Don't make this optional.  All callers have to care if we dropped the
lock.

regards,
dan carpenter