| Message ID | 1547110840-15396-1-git-send-email-vincent.guittot@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] PM/runtime: Fix autosuspend_delay on 32bits arch | expand |
* Vincent Guittot <vincent.guittot@linaro.org> [190110 09:00]: > Cast autosuspend_delay in u64 to make sure that the full computation of > expires or slack will be done in u64, even on 32bits arch. > Otherwise, any delay greater than 2^31 nsec can overflow if signed 32bits > is used when moving delay from msec to nsec > > Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") > Reported-by: Tony Lindgren <tony@atomide.com> > Tested-by: Tony Lindgren <tony@atomide.com> > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> > --- > > Change since v1: > - add u64 cast for slack computation Still works for me. Thanks, Tony
On Thursday, January 10, 2019 5:44:31 PM CET Tony Lindgren wrote: > * Vincent Guittot <vincent.guittot@linaro.org> [190110 09:00]: > > Cast autosuspend_delay in u64 to make sure that the full computation of > > expires or slack will be done in u64, even on 32bits arch. > > Otherwise, any delay greater than 2^31 nsec can overflow if signed 32bits > > is used when moving delay from msec to nsec > > > > Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") > > Reported-by: Tony Lindgren <tony@atomide.com> > > Tested-by: Tony Lindgren <tony@atomide.com> > > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> > > --- > > > > Change since v1: > > - add u64 cast for slack computation > > Still works for me. Applied, thanks!
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 7062469..76d0676 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -141,7 +141,7 @@ u64 pm_runtime_autosuspend_expiration(struct device *dev) last_busy = READ_ONCE(dev->power.last_busy); - expires = last_busy + autosuspend_delay * NSEC_PER_MSEC; + expires = last_busy + (u64)autosuspend_delay * NSEC_PER_MSEC; if (expires <= now) expires = 0; /* Already expired. */ @@ -525,7 +525,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) * We add a slack of 25% to gather wakeups * without sacrificing the granularity. */ - u64 slack = READ_ONCE(dev->power.autosuspend_delay) * + u64 slack = (u64)READ_ONCE(dev->power.autosuspend_delay) * (NSEC_PER_MSEC >> 2); dev->power.timer_expires = expires;
Cast autosuspend_delay in u64 to make sure that the full computation of expires or slack will be done in u64, even on 32bits arch. Otherwise, any delay greater than 2^31 nsec can overflow if signed 32bits is used when moving delay from msec to nsec Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by: Tony Lindgren <tony@atomide.com> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> --- Change since v1: - add u64 cast for slack computation drivers/base/power/runtime.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)