Re: [PATCH] PM: sleep: Fix error handling in dpm_prepare()

From: Rafael J. Wysocki
Date: Thu Dec 16 2021 - 14:49:20 EST


On Thu, Dec 16, 2021 at 8:44 PM Thomas Hellström
<thomas.hellstrom@xxxxxxxxxxxxxxx> wrote:
>
> On Thu, 2021-12-16 at 20:30 +0100, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > Commit 2aa36604e824 ("PM: sleep: Avoid calling put_device() under
> > dpm_list_mtx") forgot to update the while () loop termination
> > condition to also break the loop if error is nonzero, which
> > causes the loop to become infinite if device_prepare() returns
> > an error for one device.
> >
> > Add the missing !error check.
> >
> > Fixes: 2aa36604e824 ("PM: sleep: Avoid calling put_device() under
> > dpm_list_mtx")
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
>
> Was this meant to be a Reported-by:?

Yes, it was, sorry.

> Also Cc stable? IIRC 2aa36604e824 was.

That gets added later and -stable can figure it out.

> In any case,
> Reviewed-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>

Thanks!

> > ---
> > drivers/base/power/main.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > Index: linux-pm/drivers/base/power/main.c
> > ===================================================================
> > --- linux-pm.orig/drivers/base/power/main.c
> > +++ linux-pm/drivers/base/power/main.c
> > @@ -1902,7 +1902,7 @@ int dpm_prepare(pm_message_t state)
> > device_block_probing();
> >
> > mutex_lock(&dpm_list_mtx);
> > - while (!list_empty(&dpm_list)) {
> > + while (!list_empty(&dpm_list) && !error) {
> > struct device *dev = to_device(dpm_list.next);
> >
> > get_device(dev);
> >
> >
> >
>
>