RE: [PATCH v5] PM / devfreq: Restart previous governor if new governor fails to start

From: MyungJoo Ham
Date: Tue Mar 12 2019 - 03:17:24 EST


>From: Saravana Kannan <skannan@xxxxxxxxxxxxxx>
>
>If the new governor fails to start, switch back to old governor so that the
>devfreq state is not left in some weird limbo.
>
>[Mjungjoo: assume fatal on revert failure and set df->governor to NULL]
>Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
>Signed-off-by: Saravana Kannan <skannan@xxxxxxxxxxxxxx>
>Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>

I'll modify WARN->ERROR for the case when it's fatal:

>+ if (ret) {
>+ dev_warn(dev,
>+ "%s: reverting to Governor %s failed (%d)\n",
>+ __func__, df->governor_name, ret);
>+ df->governor = NULL;
>+ }

Acked-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>


>---
>V5:
>* assume fatal on revert failure and set df->governor to NULL
>
>V4:
>* Removed prev_governor check.
>
>V3:
>* Fix NULL deref for real this time.
>* Addressed some style preferences.
>
>V2:
>* Fixed typo in commit text
>* Fixed potential NULL deref
>
> drivers/devfreq/devfreq.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>