Merge branch 'fortglx/4.5/time' of https://git.linaro.org/people/john.stultz/linux into timers/core
Get the core time(keeping) updates from John Stultz
- NTP robustness tweaks
- Another signed overflow nailed down
- More y2038 changes
- Stop alarmtimer after resume
- MAINTAINERS update
- Selftest fixes
diff --git a/MAINTAINERS b/MAINTAINERS
index 050d0e7..b2f6b04 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9348,7 +9348,7 @@
S: Maintained
F: drivers/thunderbolt/
-TIMEKEEPING, CLOCKSOURCE CORE, NTP
+TIMEKEEPING, CLOCKSOURCE CORE, NTP, ALARMTIMER
M: John Stultz <john.stultz@linaro.org>
M: Thomas Gleixner <tglx@linutronix.de>
L: linux-kernel@vger.kernel.org
@@ -9361,6 +9361,7 @@
F: include/uapi/linux/timex.h
F: kernel/time/clocksource.c
F: kernel/time/time*.c
+F: kernel/time/alarmtimer.c
F: kernel/time/ntp.c
F: tools/testing/selftests/timers/
diff --git a/include/linux/time.h b/include/linux/time.h
index beebe3a..297f09f 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -125,6 +125,32 @@
extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
+/*
+ * Validates if a timespec/timeval used to inject a time offset is valid.
+ * Offsets can be postive or negative. The value of the timeval/timespec
+ * is the sum of its fields, but *NOTE*: the field tv_usec/tv_nsec must
+ * always be non-negative.
+ */
+static inline bool timeval_inject_offset_valid(const struct timeval *tv)
+{
+ /* We don't check the tv_sec as it can be positive or negative */
+
+ /* Can't have more microseconds then a second */
+ if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
+ return false;
+ return true;
+}
+
+static inline bool timespec_inject_offset_valid(const struct timespec *ts)
+{
+ /* We don't check the tv_sec as it can be positive or negative */
+
+ /* Can't have more nanoseconds then a second */
+ if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC)
+ return false;
+ return true;
+}
+
#define CURRENT_TIME (current_kernel_time())
#define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 })
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 7fbba63..e840ed8 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -271,11 +271,27 @@
__pm_wakeup_event(ws, MSEC_PER_SEC);
return ret;
}
+
+static int alarmtimer_resume(struct device *dev)
+{
+ struct rtc_device *rtc;
+
+ rtc = alarmtimer_get_rtcdev();
+ if (rtc)
+ rtc_timer_cancel(rtc, &rtctimer);
+ return 0;
+}
+
#else
static int alarmtimer_suspend(struct device *dev)
{
return 0;
}
+
+static int alarmtimer_resume(struct device *dev)
+{
+ return 0;
+}
#endif
static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
@@ -800,6 +816,7 @@
/* Suspend hook structures */
static const struct dev_pm_ops alarmtimer_pm_ops = {
.suspend = alarmtimer_suspend,
+ .resume = alarmtimer_resume,
};
static struct platform_driver alarmtimer_driver = {
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 1347882..664de53 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -218,8 +218,8 @@
/* Check the deviation from the watchdog clocksource. */
if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) {
- pr_warn("timekeeping watchdog: Marking clocksource '%s' as unstable because the skew is too large:\n",
- cs->name);
+ pr_warn("timekeeping watchdog on CPU%d: Marking clocksource '%s' as unstable because the skew is too large:\n",
+ smp_processor_id(), cs->name);
pr_warn(" '%s' wd_now: %llx wd_last: %llx mask: %llx\n",
watchdog->name, wdnow, wdlast, watchdog->mask);
pr_warn(" '%s' cs_now: %llx cs_last: %llx mask: %llx\n",
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 149cc80..36f2ca0 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -16,8 +16,11 @@
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/rtc.h>
+#include <linux/math64.h>
#include "ntp_internal.h"
+#include "timekeeping_internal.h"
+
/*
* NTP timekeeping variables:
@@ -70,7 +73,7 @@
static s64 time_freq;
/* time at last adjustment (secs): */
-static long time_reftime;
+static time64_t time_reftime;
static long time_adjust;
@@ -297,25 +300,27 @@
if (!(time_status & STA_PLL))
return;
- if (!(time_status & STA_NANO))
+ if (!(time_status & STA_NANO)) {
+ /* Make sure the multiplication below won't overflow */
+ offset = clamp(offset, -USEC_PER_SEC, USEC_PER_SEC);
offset *= NSEC_PER_USEC;
+ }
/*
* Scale the phase adjustment and
* clamp to the operating range.
*/
- offset = min(offset, MAXPHASE);
- offset = max(offset, -MAXPHASE);
+ offset = clamp(offset, -MAXPHASE, MAXPHASE);
/*
* Select how the frequency is to be controlled
* and in which mode (PLL or FLL).
*/
- secs = get_seconds() - time_reftime;
+ secs = (long)(__ktime_get_real_seconds() - time_reftime);
if (unlikely(time_status & STA_FREQHOLD))
secs = 0;
- time_reftime = get_seconds();
+ time_reftime = __ktime_get_real_seconds();
offset64 = offset;
freq_adj = ntp_update_offset_fll(offset64, secs);
@@ -390,10 +395,11 @@
*
* Also handles leap second processing, and returns leap offset
*/
-int second_overflow(unsigned long secs)
+int second_overflow(time64_t secs)
{
s64 delta;
int leap = 0;
+ s32 rem;
/*
* Leap second processing. If in leap-insert state at the end of the
@@ -404,19 +410,19 @@
case TIME_OK:
if (time_status & STA_INS) {
time_state = TIME_INS;
- ntp_next_leap_sec = secs + SECS_PER_DAY -
- (secs % SECS_PER_DAY);
+ div_s64_rem(secs, SECS_PER_DAY, &rem);
+ ntp_next_leap_sec = secs + SECS_PER_DAY - rem;
} else if (time_status & STA_DEL) {
time_state = TIME_DEL;
- ntp_next_leap_sec = secs + SECS_PER_DAY -
- ((secs+1) % SECS_PER_DAY);
+ div_s64_rem(secs + 1, SECS_PER_DAY, &rem);
+ ntp_next_leap_sec = secs + SECS_PER_DAY - rem;
}
break;
case TIME_INS:
if (!(time_status & STA_INS)) {
ntp_next_leap_sec = TIME64_MAX;
time_state = TIME_OK;
- } else if (secs % SECS_PER_DAY == 0) {
+ } else if (secs == ntp_next_leap_sec) {
leap = -1;
time_state = TIME_OOP;
printk(KERN_NOTICE
@@ -427,7 +433,7 @@
if (!(time_status & STA_DEL)) {
ntp_next_leap_sec = TIME64_MAX;
time_state = TIME_OK;
- } else if ((secs + 1) % SECS_PER_DAY == 0) {
+ } else if (secs == ntp_next_leap_sec) {
leap = 1;
ntp_next_leap_sec = TIME64_MAX;
time_state = TIME_WAIT;
@@ -590,7 +596,7 @@
* reference time to current time.
*/
if (!(time_status & STA_PLL) && (txc->status & STA_PLL))
- time_reftime = get_seconds();
+ time_reftime = __ktime_get_real_seconds();
/* only set allowed bits */
time_status &= STA_RONLY;
@@ -674,8 +680,14 @@
return -EINVAL;
}
- if ((txc->modes & ADJ_SETOFFSET) && (!capable(CAP_SYS_TIME)))
- return -EPERM;
+ if (txc->modes & ADJ_SETOFFSET) {
+ /* In order to inject time, you gotta be super-user! */
+ if (!capable(CAP_SYS_TIME))
+ return -EPERM;
+
+ if (!timeval_inject_offset_valid(&txc->time))
+ return -EINVAL;
+ }
/*
* Check for potential multiplication overflows that can
diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h
index af92447..d8a7c11 100644
--- a/kernel/time/ntp_internal.h
+++ b/kernel/time/ntp_internal.h
@@ -6,7 +6,7 @@
/* Returns how long ticks are at present, in ns / 2^NTP_SCALE_SHIFT. */
extern u64 ntp_tick_length(void);
extern ktime_t ntp_get_next_leap(void);
-extern int second_overflow(unsigned long secs);
+extern int second_overflow(time64_t secs);
extern int ntp_validate_timex(struct timex *);
extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *);
extern void __hardpps(const struct timespec64 *, const struct timespec64 *);
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index d563c19..34b4ced 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -305,8 +305,7 @@
delta = timekeeping_get_delta(tkr);
- nsec = delta * tkr->mult + tkr->xtime_nsec;
- nsec >>= tkr->shift;
+ nsec = (delta * tkr->mult + tkr->xtime_nsec) >> tkr->shift;
/* If arch requires, add in get_arch_timeoffset() */
return nsec + arch_gettimeoffset();
@@ -846,6 +845,19 @@
}
EXPORT_SYMBOL_GPL(ktime_get_real_seconds);
+/**
+ * __ktime_get_real_seconds - The same as ktime_get_real_seconds
+ * but without the sequence counter protect. This internal function
+ * is called just when timekeeping lock is already held.
+ */
+time64_t __ktime_get_real_seconds(void)
+{
+ struct timekeeper *tk = &tk_core.timekeeper;
+
+ return tk->xtime_sec;
+}
+
+
#ifdef CONFIG_NTP_PPS
/**
@@ -959,7 +971,7 @@
struct timespec64 ts64, tmp;
int ret = 0;
- if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
+ if (!timespec_inject_offset_valid(ts))
return -EINVAL;
ts64 = timespec_to_timespec64(*ts);
@@ -1592,9 +1604,12 @@
{
s64 interval = tk->cycle_interval;
s64 xinterval = tk->xtime_interval;
+ u32 base = tk->tkr_mono.clock->mult;
+ u32 max = tk->tkr_mono.clock->maxadj;
+ u32 cur_adj = tk->tkr_mono.mult;
s64 tick_error;
bool negative;
- u32 adj;
+ u32 adj_scale;
/* Remove any current error adj from freq calculation */
if (tk->ntp_err_mult)
@@ -1613,13 +1628,33 @@
/* preserve the direction of correction */
negative = (tick_error < 0);
- /* Sort out the magnitude of the correction */
+ /* If any adjustment would pass the max, just return */
+ if (negative && (cur_adj - 1) <= (base - max))
+ return;
+ if (!negative && (cur_adj + 1) >= (base + max))
+ return;
+ /*
+ * Sort out the magnitude of the correction, but
+ * avoid making so large a correction that we go
+ * over the max adjustment.
+ */
+ adj_scale = 0;
tick_error = abs(tick_error);
- for (adj = 0; tick_error > interval; adj++)
+ while (tick_error > interval) {
+ u32 adj = 1 << (adj_scale + 1);
+
+ /* Check if adjustment gets us within 1 unit from the max */
+ if (negative && (cur_adj - adj) <= (base - max))
+ break;
+ if (!negative && (cur_adj + adj) >= (base + max))
+ break;
+
+ adj_scale++;
tick_error >>= 1;
+ }
/* scale the corrections */
- timekeeping_apply_adjustment(tk, offset, negative, adj);
+ timekeeping_apply_adjustment(tk, offset, negative, adj_scale);
}
/*
diff --git a/kernel/time/timekeeping_internal.h b/kernel/time/timekeeping_internal.h
index 4ea005a..e20466f 100644
--- a/kernel/time/timekeeping_internal.h
+++ b/kernel/time/timekeeping_internal.h
@@ -26,4 +26,6 @@
}
#endif
+extern time64_t __ktime_get_real_seconds(void);
+
#endif /* _TIMEKEEPING_INTERNAL_H */
diff --git a/tools/testing/selftests/timers/clocksource-switch.c b/tools/testing/selftests/timers/clocksource-switch.c
index 627ec74..fd88e30 100644
--- a/tools/testing/selftests/timers/clocksource-switch.c
+++ b/tools/testing/selftests/timers/clocksource-switch.c
@@ -97,7 +97,7 @@
int change_clocksource(char *clocksource)
{
int fd;
- size_t size;
+ ssize_t size;
fd = open("/sys/devices/system/clocksource/clocksource0/current_clocksource", O_WRONLY);