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Date: Wed, 23 May 2018 16:50:06 -0500
From: Bjorn Helgaas <helgaas@kernel.org>
To: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
 kernel-janitors@vger.kernel.org, Paul Mackerras <paulus@samba.org>,
 Michael Ellerman <mpe@ellerman.id.au>,
 Bjorn Helgaas <bhelgaas@google.com>, linuxppc-dev@lists.ozlabs.org,
 linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/5] pci/hotplug/pnv-php: add missing of_node_put
Message-ID: <20180523215006.GF150632@bhelgaas-glaptop.roam.corp.google.com>
References: <1527102436-13447-1-git-send-email-Julia.Lawall@lip6.fr>
 <1527102436-13447-5-git-send-email-Julia.Lawall@lip6.fr>
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On Wed, May 23, 2018 at 09:07:15PM +0200, Julia Lawall wrote:
> The device node iterators perform an of_node_get on each iteration, so a
> jump out of the loop requires an of_node_put.
> 
> The semantic patch that fixes this problem is as follows
> (http://coccinelle.lip6.fr):
> 
> // <smpl>
> @@
> expression root,e;
> local idexpression child;
> iterator name for_each_child_of_node;
> @@
> 
>  for_each_child_of_node(root, child) {
>    ... when != of_node_put(child)
>        when != e = child
> +  of_node_put(child);
> ?  break;
>    ...
> }
> ... when != child
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied to pci/hotplug for v4.18, thanks!

> ---
>  drivers/pci/hotplug/pnv_php.c |    8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c
> index d441006..6c2e8d7 100644
> --- a/drivers/pci/hotplug/pnv_php.c
> +++ b/drivers/pci/hotplug/pnv_php.c
> @@ -220,12 +220,16 @@ static int pnv_php_populate_changeset(struct of_changeset *ocs,
>  
>  	for_each_child_of_node(dn, child) {
>  		ret = of_changeset_attach_node(ocs, child);
> -		if (ret)
> +		if (ret) {
> +			of_node_put(child);
>  			break;
> +		}
>  
>  		ret = pnv_php_populate_changeset(ocs, child);
> -		if (ret)
> +		if (ret) {
> +			of_node_put(child);
>  			break;
> +		}
>  	}
>  
>  	return ret;
>