Re: next: suspicious RCU usage message since commit 'rcu: Remove superfluous versions of rcu_read_lock_sched_held()'

[Guenter Roeck <linux@roeck-us.net>]

On 04/25/2016 01:49 PM, Paul E. McKenney wrote:
> On Mon, Apr 25, 2016 at 01:25:10PM -0700, Guenter Roeck wrote:
>> On Mon, Apr 25, 2016 at 10:12:39AM -0700, Paul E. McKenney wrote:
>>> On Sun, Apr 24, 2016 at 11:26:41PM -0700, Guenter Roeck wrote:
>>>> On 04/24/2016 10:49 PM, Paul E. McKenney wrote:
>>>>> On Sun, Apr 24, 2016 at 10:37:25PM -0700, Guenter Roeck wrote:
>>>>>> On 04/24/2016 10:28 PM, Paul E. McKenney wrote:
>>>>>>> On Sun, Apr 24, 2016 at 04:56:38PM -0700, Guenter Roeck wrote:
>>>
>>> [ . . . ]
>>>
>>>>>>>> After making the same change in _pwrdm_state_switch(), the traceback is gone
>>>>>>> >from my tests (beagle, beagle-xm, and overo-tobi).
>>>>>>>
>>>>>>> Very good!
>>>>>>>
>>>>>>> (And yes, you normally find these one at a time...)
>>>>>>>
>>>>>> Are you going to submit a formal patch ?
>>>>>
>>>>> I can, but please feel free to send mine along with yours, if you wish.
>>>>>
>>>> I think it would be best if you send a single patch which fixes both calls.
>>>
>>> Like this one?
>>>
>>> If so, could you please run it to make sure that it actually fixes the
>>> problem?  And if it does, would you be willing to give me a Tested-by?
>>>
>> It does. Tested-by: inline below.
>
> Got it, thank you!
>
> If the ARM guys are willing to take this, it might hit the next merge
> window, or perhaps they will take it as an exception.  If I push it
> up my usual route, it will be a bit later.
>
> I just now sent it out, so hopefully they will grab it.  ;-)
>
Hi Paul,

Either it fixes a zero-day bug which was exposed by 'rcu: Remove superfluous
versions ...", or it fixes a problem with that commit, so I would hope that
_someone_ will pick it up.

Anyway, thanks a lot for looking into it, and for the patch!

Guenter