Re:Re: [PATCH] of: device: Fix missing of_node_put() in of_dma_set_restricted_buffer

["Liang He" <windhl@126.com>]

At 2022-07-05 22:45:27, "Rob Herring" <robh@kernel.org> wrote:
>On Sat, Jul 02, 2022 at 09:44:49AM +0800, Liang He wrote:
>> We should use of_node_put() for the reference 'node' returned by
>> of_parse_phandle() which will increase the refcount.
>> 
>> Fixes: fec9b625095f ("of: Add plumbing for restricted DMA pool")
>> Co-authored-by: Miaoqian Lin <linmq006@gmail.com>
>> Signed-off-by: Liang He <windhl@126.com>
>> ---
>>  drivers/of/device.c | 5 ++++-
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/of/device.c b/drivers/of/device.c
>> index 874f031442dc..75b6cbffa755 100644
>> --- a/drivers/of/device.c
>> +++ b/drivers/of/device.c
>> @@ -81,8 +81,11 @@ of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
>>  		 * restricted-dma-pool region is allowed.
>>  		 */
>>  		if (of_device_is_compatible(node, "restricted-dma-pool") &&
>> -		    of_device_is_available(node))
>> +		    of_device_is_available(node)) {
>> +			of_node_put(node);
>>  			break;
>> +		}
>> +		of_node_put(node);
>
>This should be converted to use of_for_each_phandle() iterator instead. 
>That takes care of the put here (but not in the break).
>
>Rob

Hi, Rob.

After I carefully read the implementation of of_for_each_phandle() and of_parse_phandle(),
I think it is better to keep current coding style as it will change a lot of current code.

Besides, the loop index 'i' will be used in following of_reserved_mem_device_init_by_idx(), so
I cannot give a simple and correct way to use of_for_each_phandle().

Thanks, 

Liang