Hi Nick, On 25/09/2019 14:32:09-0600, Nick Crews wrote: > If the RTC HW returns an invalid time, the rtc_year_days() > call would crash. This patch adds error logging in this > situation, and removes the tm_yday and tm_wday calculations. > These fields should not be relied upon by userspace > according to man rtc, and thus we don't need to calculate > them. > > Signed-off-by: Nick Crews <[email protected]> > --- > drivers/rtc/rtc-wilco-ec.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c > index 8ad4c4e6d557..53da355d996a 100644 > --- a/drivers/rtc/rtc-wilco-ec.c > +++ b/drivers/rtc/rtc-wilco-ec.c > @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct > rtc_time *tm) > tm->tm_mday = rtc.day; > tm->tm_mon = rtc.month - 1; > tm->tm_year = rtc.year + (rtc.century * 100) - 1900; > - tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); > - > - /* Don't compute day of week, we don't need it. */ > - tm->tm_wday = -1; > + /* Ignore other tm fields, man rtc says userspace shouldn't use them. */ > + > + if (rtc_valid_tm(tm)) { > + dev_err(dev, > + "Time from RTC is invalid: second=%u, minute=%u, > hour=%u, day=%u, month=%u, year=%u, century=%u", > + rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month, > + rtc.year, rtc.century);
Do you mind using %ptR? At this point you already filled the tm struct anyway and if you print century separately, you can infer tm_year. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
