Re: [PATCH v2 2/2] of: __of_detach_node() - remove node from phandle cache

[Frank Rowand <frowand.list@gmail.com>]

On 12/18/18 12:01 PM, Rob Herring wrote:
> On Tue, Dec 18, 2018 at 12:57 PM Frank Rowand <frowand.list@gmail.com> wrote:
>>
>> On 12/17/18 2:52 AM, Michael Ellerman wrote:
>>> Hi Frank,
>>>
>>> frowand.list@gmail.com writes:
>>>> From: Frank Rowand <frank.rowand@sony.com>
>>>>
>>>> Non-overlay dynamic devicetree node removal may leave the node in
>>>> the phandle cache.  Subsequent calls to of_find_node_by_phandle()
>>>> will incorrectly find the stale entry.  Remove the node from the
>>>> cache.
>>>>
>>>> Add paranoia checks in of_find_node_by_phandle() as a second level
>>>> of defense (do not return cached node if detached, do not add node
>>>> to cache if detached).
>>>>
>>>> Reported-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
>>>> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
>>>> ---
>>>
>>> Similarly here can we add:
>>>
>>> Fixes: 0b3ce78e90fc ("of: cache phandle nodes to reduce cost of of_find_node_by_phandle()")
>>
>> Yes, thanks.
>>
>>
>>> Cc: stable@vger.kernel.org # v4.17+
>>
>> Nope, 0b3ce78e90fc does not belong in stable (it is a feature, not a bug
>> fix).  So the bug will not be in stable.
> 
> 0b3ce78e90fc landed in v4.17, so Michael's line above is correct.
> Annotating it with 4.17 only saves Greg from trying and then emailing
> us to backport this patch as it wouldn't apply.

Thanks for the correction.  I was both under-thinking and over-thinking,
ending up with an incorrect answer.

Can you add the Cc: to version 3 patch comments (both 1/2 and 2/2) or do
you want me to re-spin?

-Frank

> 
> Rob
>