Re: [PATCH 01/15] ARM: actions: fix a leaked reference by addingmissing of_node_put

From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To: Wen Yang <wen.yang99@zte.com.cn>,
	linus.walleij@linaro.org, afaerber@suse.de
Cc: liviu.dudau@arm.com, sudeep.holla@arm.com,
	lorenzo.pieralisi@arm.com, linux@armlinux.org.uk,
	linux-arm-kernel@lists.infradead.org,
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	linux-samsung-soc@vger.kernel.org, michal.simek@xilinx.com,
	dinguyen@kernel.org, heiko@sntech.de,
	linux-rockchip@lists.infradead.org, f.fainelli@gmail.com,
	rjui@broadcom.com, sbranden@broadcom.com,
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	shawnguo@kernel.org, s.hauer@pengutronix.de,
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	wang.yi59@zte.com.cn
Subject: Re: [PATCH 01/15] ARM: actions: fix a leaked reference by addingmissing of_node_put
Date: Fri, 1 Mar 2019 21:25:23 +0530	[thread overview]
Message-ID: <20190301155523.GA1915@Mani-XPS-13-9360> (raw)
In-Reply-To: <1551430616-42014-1-git-send-email-wen.yang99@zte.com.cn>

Hi Wen,

On Fri, Mar 01, 2019 at 04:56:42PM +0800, Wen Yang wrote:
> The call to of_get_next_child returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
> 
> Detected by coccinelle with the following warnings:
> ./arch/arm/mach-actions/platsmp.c:112:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 103, but without a corresponding object release within this function.
> ./arch/arm/mach-actions/platsmp.c:124:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 115, but without a corresponding object release within this function.
> ./arch/arm/mach-actions/platsmp.c:137:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 128, but without a corresponding object release within this function.
> 

We have a floating patch for this:
https://www.spinics.net/lists/arm-kernel/msg694544.html

Andreas: Can you please take a second look at the patchset submitted by Linus
Walleij and Russel for simplifying the Actions startup code?

Thanks,
Mani

> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: "Andreas Färber" <afaerber@suse.de>
> Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  arch/arm/mach-actions/platsmp.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/arm/mach-actions/platsmp.c b/arch/arm/mach-actions/platsmp.c
> index 4fd479c..1a8e078 100644
> --- a/arch/arm/mach-actions/platsmp.c
> +++ b/arch/arm/mach-actions/platsmp.c
> @@ -107,6 +107,7 @@ static void __init s500_smp_prepare_cpus(unsigned int max_cpus)
>  	}
>  
>  	timer_base_addr = of_iomap(node, 0);
> +	of_node_put(node);
>  	if (!timer_base_addr) {
>  		pr_err("%s: could not map timer registers\n", __func__);
>  		return;
> @@ -119,6 +120,7 @@ static void __init s500_smp_prepare_cpus(unsigned int max_cpus)
>  	}
>  
>  	sps_base_addr = of_iomap(node, 0);
> +	of_node_put(node);
>  	if (!sps_base_addr) {
>  		pr_err("%s: could not map sps registers\n", __func__);
>  		return;
> @@ -132,6 +134,7 @@ static void __init s500_smp_prepare_cpus(unsigned int max_cpus)
>  		}
>  
>  		scu_base_addr = of_iomap(node, 0);
> +		of_node_put(node);
>  		if (!scu_base_addr) {
>  			pr_err("%s: could not map scu registers\n", __func__);
>  			return;
> -- 
> 2.9.5
> 