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Date:   Thu, 16 Jun 2022 15:14:45 +0200
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Liang He <windhl@126.com>
Cc:     lpieralisi@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] bus: (mvebu-mbus) Add missing of_node_put()
Message-ID: <20220616131445.fm4pyrsodo624vwz@pali>
References: <20220616020135.3973141-1-windhl@126.com>
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On Thursday 16 June 2022 10:01:35 Liang He wrote:
> In mvebu_mbus_dt_init(), of_find_matching_node_and_match() and
> of_find_node_by_phandle() will both return node pointers with
> refcount incremented. We should use of_node_put() in fail path
> or when it is not used anymore.
> 
> Signed-off-by: Liang He <windhl@126.com>

Acked-by: Pali Rohár <pali@kernel.org>

> ---
>  changelog:
> 
>   v2: (1) use real name (2) add of_node_put when not used anymore
> 
>   v1: add of_node_put in fail path
> 
> 
>  drivers/bus/mvebu-mbus.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c
> index db612045616f..e168c8de2ae8 100644
> --- a/drivers/bus/mvebu-mbus.c
> +++ b/drivers/bus/mvebu-mbus.c
> @@ -1327,22 +1327,28 @@ int __init mvebu_mbus_dt_init(bool is_coherent)
>  
>  	prop = of_get_property(np, "controller", NULL);
>  	if (!prop) {
> +		of_node_put(np);
>  		pr_err("required 'controller' property missing\n");
>  		return -EINVAL;
>  	}
>  
>  	controller = of_find_node_by_phandle(be32_to_cpup(prop));
>  	if (!controller) {
> +		of_node_put(np);
>  		pr_err("could not find an 'mbus-controller' node\n");
>  		return -ENODEV;
>  	}
>  
>  	if (of_address_to_resource(controller, 0, &mbuswins_res)) {
> +		of_node_put(np);
> +		of_node_put(controller);
>  		pr_err("cannot get MBUS register address\n");
>  		return -EINVAL;
>  	}
>  
>  	if (of_address_to_resource(controller, 1, &sdramwins_res)) {
> +		of_node_put(np);
> +		of_node_put(controller);
>  		pr_err("cannot get SDRAM register address\n");
>  		return -EINVAL;
>  	}
> @@ -1360,6 +1366,8 @@ int __init mvebu_mbus_dt_init(bool is_coherent)
>  			pr_warn(FW_WARN "deprecated mbus-mvebu Device Tree, suspend/resume will not work\n");
>  	}
>  
> +	of_node_put(controller);	
> +
>  	mbus_state.hw_io_coherency = is_coherent;
>  
>  	/* Get optional pcie-{mem,io}-aperture properties */
> @@ -1378,6 +1386,11 @@ int __init mvebu_mbus_dt_init(bool is_coherent)
>  		return ret;
>  
>  	/* Setup statically declared windows in the DT */
> -	return mbus_dt_setup(&mbus_state, np);
> +	ret = mbus_dt_setup(&mbus_state, np);
> +
> +	of_node_put(np);
> +	
> +	return ret;
> +
>  }
>  #endif
> -- 
> 2.25.1
>