Re: [PATCH v6 07/18] of: dynamic: change type of of_{at,de}tach_node() to void

[Michael Ellerman]

Frank Rowand <frowand.list@xxxxxxxxx> writes:
> On 11/7/18 4:08 AM, Michael Ellerman wrote:
>> frowand.list@xxxxxxxxx writes:
>> 
>>> From: Frank Rowand <frank.rowand@xxxxxxxx>
>>>
>>> of_attach_node() and of_detach_node() always return zero, so
>>> their return value is meaningless.
>> 
>> But should they always return zero?
>> 
>> At least __of_attach_node_sysfs() can fail in several ways.
>
> Sigh.  And of_reconfig_notify() can fail.  And at one point in the
> history the return value of of_reconfig_notify() was returned by
> of_attach_node() if of_reconfig_notify() failed.
>
>> And there's also this in __of_detach_node() which should probably be
>> returning an error:
>> 
>> 	if (WARN_ON(of_node_check_flag(np, OF_DETACHED)))
>>         	return;
>> 
>> 
>> Seems to me we should instead be fixing these to propagate errors,
>> rather than hiding them?
>
> The history of how of_attach_node() stopped propagating errors is
> a bit more complex than I want to dig into at the moment.  So I'll
> drop this patch from the series and add investigating this onto
> my todo list.  I suspect that the result of investigating will be
> that error return values should not be ignored in of_attach_node()
> and of_detach_node(), but should instead be propagated to the
> callers, as you suggest.

Thanks.

cheers