diff options
Diffstat (limited to 'drivers/base/power/trace.c')
| -rw-r--r-- | drivers/base/power/trace.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c index efec10b49d59..1cda505d6a85 100644 --- a/drivers/base/power/trace.c +++ b/drivers/base/power/trace.c @@ -10,6 +10,7 @@ #include <linux/pm-trace.h> #include <linux/export.h> #include <linux/rtc.h> +#include <linux/suspend.h> #include <linux/mc146818rtc.h> @@ -74,6 +75,9 @@ #define DEVSEED (7919) +bool pm_trace_rtc_abused __read_mostly; +EXPORT_SYMBOL_GPL(pm_trace_rtc_abused); + static unsigned int dev_hash_value; static int set_magic_time(unsigned int user, unsigned int file, unsigned int device) @@ -104,6 +108,7 @@ static int set_magic_time(unsigned int user, unsigned int file, unsigned int dev time.tm_min = (n % 20) * 3; n /= 20; mc146818_set_time(&time); + pm_trace_rtc_abused = true; return n ? -1 : 0; } @@ -239,9 +244,31 @@ int show_trace_dev_match(char *buf, size_t size) return ret; } +static int +pm_trace_notify(struct notifier_block *nb, unsigned long mode, void *_unused) +{ + switch (mode) { + case PM_POST_HIBERNATION: + case PM_POST_SUSPEND: + if (pm_trace_rtc_abused) { + pm_trace_rtc_abused = false; + pr_warn("Possible incorrect RTC due to pm_trace, please use 'ntpdate' or 'rdate' to reset it.\n"); + } + break; + default: + break; + } + return 0; +} + +static struct notifier_block pm_trace_nb = { + .notifier_call = pm_trace_notify, +}; + static int early_resume_init(void) { hash_value_early_read = read_magic_time(); + register_pm_notifier(&pm_trace_nb); return 0; } |