Re: [PATCH] cpuidle: menu: Do not return a disabled idle state

[Rafael J. Wysocki (Intel)]

On Thu, Aug 27, 2026 at 11:48 AM Xueqin Luo <luoxueqin@xxxxxxxxxx> wrote:
>
> When idle state 0 is disabled and the PM QoS latency constraint is
> zero (latency_req == 0), the first branch of the || in the early-return
> condition of menu_select() is taken immediately, so state 0 is returned
> regardless of its disable flag.
>
> Address this by making the !disable check a prerequisite for the entire
> early-return condition, so that when state 0 is disabled the normal
> state selection loop is used instead, which already skips disabled
> states.
>
> Fixes: 53812cdc9100 ("cpuidle: menu: Move the latency_req == 0 special case check")
> Signed-off-by: Xueqin Luo <luoxueqin@xxxxxxxxxx>
> ---
>  drivers/cpuidle/governors/menu.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
> index 544a5d593007..eb529d73d4b7 100644
> --- a/drivers/cpuidle/governors/menu.c
> +++ b/drivers/cpuidle/governors/menu.c
> @@ -284,10 +284,10 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev,
>                 data->bucket = BUCKETS - 1;
>         }
>
> -       if (latency_req == 0 ||
> -           ((data->next_timer_ns < drv->states[1].target_residency_ns ||
> -             latency_req < drv->states[1].exit_latency_ns) &&
> -            !dev->states_usage[0].disable)) {
> +       if (!dev->states_usage[0].disable &&
> +           (latency_req == 0 ||
> +            data->next_timer_ns < drv->states[1].target_residency_ns ||
> +            latency_req < drv->states[1].exit_latency_ns)) {
>                 /*
>                  * In this case state[0] will be used no matter what, so return
>                  * it right away and keep the tick running if state[0] is a
> --

Applied as 7.4 material, thanks!