Re: [PATCH] PM / devfreq: Fix faulty error message

From: MyungJoo Ham
Date: Wed Mar 18 2015 - 00:12:54 EST


> The misleading log "releasing devfreq which doesn't exist" prints out
> for well behaved clients. This is due to the fact that _remove_devfreq
> calls itself recursively by proxy (via put_device()). The second time
> _devfreq_remove is called the respective device has already been
> deleted, causing the misleading warning.
>
> So just skip printing the message if _devfreq_remove was called via
> put_device().
>
> Signed-off-by: Deva Ramasubramanian <dramasub@xxxxxxxxxxxxxx>
> ---
> drivers/devfreq/devfreq.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 30b538d8..bee59db 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -399,7 +399,8 @@ static void _remove_devfreq(struct devfreq *devfreq)
> mutex_lock(&devfreq_list_lock);
> if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) {
> mutex_unlock(&devfreq_list_lock);
> - dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n");
> + if (!skip)
> + dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n");

There is no variable 'skip' in the function. (you get build error.)
And with patch 585fc83ece43be63, we do not call the function recursively, either.

---
drivers/devfreq/devfreq.c: In function â_remove_devfreqâ:
drivers/devfreq/devfreq.c:402:8: error: âskipâ undeclared (first use in this function)
drivers/devfreq/devfreq.c:402:8: note: each undeclared identifier is reported only once for each function it appears in
make[2]: *** [drivers/devfreq/devfreq.o] Error 1
make[1]: *** [drivers/devfreq] Error 2
make[1]: *** Waiting for unfinished jobs....
---

I'll update the function description.


Cheers,
MyungJoo.

> return;
> }
> list_del(&devfreq->node);
> --
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