Re: [PATCH] PM / sleep: Do not assume that "mem" is always present

From: Rafael J. Wysocki
Date: Wed Oct 20 2021 - 09:54:43 EST


On Wed, Sep 15, 2021 at 2:05 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
>
> On Wed, Sep 15, 2021 at 4:23 AM Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
> >
> > An implementation of suspend_ops is allowed to reject the PM_SUSPEND_MEM
> > suspend type from its ->valid() callback, we should not assume that it
> > is always present as this is not a correct reflection of what a firmware
> > interface may support.
> >
> > Fixes: 406e79385f32 ("PM / sleep: System sleep state selection interface rework")
> > Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> > ---
> > kernel/power/suspend.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
> > index eb75f394a059..02e306ad8db8 100644
> > --- a/kernel/power/suspend.c
> > +++ b/kernel/power/suspend.c
> > @@ -171,8 +171,7 @@ static bool valid_state(suspend_state_t state)
> >
> > void __init pm_states_init(void)
> > {
> > - /* "mem" and "freeze" are always present in /sys/power/state. */
> > - pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
> > + /* "freeze" is always present in /sys/power/state. */
> > pm_states[PM_SUSPEND_TO_IDLE] = pm_labels[PM_SUSPEND_TO_IDLE];
> > /*
> > * Suspend-to-idle should be supported even without any suspend_ops,
> > @@ -214,6 +213,7 @@ void suspend_set_ops(const struct platform_suspend_ops *ops)
> > }
> > if (valid_state(PM_SUSPEND_MEM)) {
> > mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
> > + pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
> > if (mem_sleep_default >= PM_SUSPEND_MEM)
> > mem_sleep_current = PM_SUSPEND_MEM;
> > }
> > --
>
> Applied as 5.16 material, thanks!

And reverted as per
https://lore.kernel.org/linux-pm/d36f79b4-472c-4852-7370-a011f9f556ce@xxxxxxxxx/