| Message ID | 1414388802-5866-4-git-send-email-pang.xunlei@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Mon, 27 Oct 2014, pang.xunlei wrote: > The kernel uses 32-bit signed value(time_t) for seconds since 1970-01-01:00:00:00, so it > will overflow at 2038-01-19 03:14:08 on 32-bit systems. We call this "2038 safety" issue. We really know that by now. No need to repeat that for every patch. > As part of addressing 2038 saftey for in-kernel uses, this patch creates no functional change > in existing users, and converts rtc_tm_to_time_unsafe() to rtc_tm_to_time() in rtc_hctosys(). Please line break your changelogs properly. That's how it should look like: > As part of addressing 2038 saftey for in-kernel uses, this patch > creates no functional change in existing users, and converts > rtc_tm_to_time_unsafe() to rtc_tm_to_time() in rtc_hctosys(). Can you spot the difference? > @@ -26,9 +26,10 @@ static int __init rtc_hctosys(void) > { > int err = -ENODEV; > struct rtc_time tm; > - struct timespec tv = { > + struct timespec64 tv = { > .tv_nsec = NSEC_PER_SEC >> 1, > }; > + struct timespec ts32; So this is exactly why I dislike this whole flag day conversion thing. If you add rtc_tm_to_time64() do_settimeofday64() in the first place, you can convert the whole function in one go without introducing intermediate variables which then need to be undone later again. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On Mon, 27 Oct 2014, Thomas Gleixner wrote: > On Mon, 27 Oct 2014, pang.xunlei wrote: > > The kernel uses 32-bit signed value(time_t) for seconds since 1970-01-01:00:00:00, so it > > will overflow at 2038-01-19 03:14:08 on 32-bit systems. We call this "2038 safety" issue. > > We really know that by now. No need to repeat that for every patch. > > > As part of addressing 2038 saftey for in-kernel uses, this patch creates no functional change > > in existing users, and converts rtc_tm_to_time_unsafe() to rtc_tm_to_time() in rtc_hctosys(). > > Please line break your changelogs properly. That's how it should look > like: > > > As part of addressing 2038 saftey for in-kernel uses, this patch > > creates no functional change in existing users, and converts > > rtc_tm_to_time_unsafe() to rtc_tm_to_time() in rtc_hctosys(). > > Can you spot the difference? > > > @@ -26,9 +26,10 @@ static int __init rtc_hctosys(void) > > { > > int err = -ENODEV; > > struct rtc_time tm; > > - struct timespec tv = { > > + struct timespec64 tv = { > > .tv_nsec = NSEC_PER_SEC >> 1, > > }; > > + struct timespec ts32; > > So this is exactly why I dislike this whole flag day conversion > thing. If you add > > rtc_tm_to_time64() > do_settimeofday64() > > in the first place, you can convert the whole function in one go > without introducing intermediate variables which then need to be > undone later again. Aside of that ts32 is a complete misnomer because on 64 bit struct timespec already has a 64bit seconds representation. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/drivers/rtc/hctosys.c b/drivers/rtc/hctosys.c index 4e9a5c6..c80723f 100644 --- a/drivers/rtc/hctosys.c +++ b/drivers/rtc/hctosys.c @@ -26,9 +26,10 @@ static int __init rtc_hctosys(void) { int err = -ENODEV; struct rtc_time tm; - struct timespec tv = { + struct timespec64 tv = { .tv_nsec = NSEC_PER_SEC >> 1, }; + struct timespec ts32; struct rtc_device *rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE); if (rtc == NULL) { @@ -52,16 +53,17 @@ static int __init rtc_hctosys(void) goto err_invalid; } - rtc_tm_to_time_unsafe(&tm, &tv.tv_sec); + rtc_tm_to_time(&tm, &tv.tv_sec); - err = do_settimeofday(&tv); + ts32 = timespec64_to_timespec(tv); + err = do_settimeofday(&ts32); dev_info(rtc->dev.parent, "setting system clock to " - "%d-%02d-%02d %02d:%02d:%02d UTC (%u)\n", + "%d-%02d-%02d %02d:%02d:%02d UTC (%llu)\n", tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec, - (unsigned int) tv.tv_sec); + (unsigned long long) tv.tv_sec); err_invalid: err_read:
The kernel uses 32-bit signed value(time_t) for seconds since 1970-01-01:00:00:00, so it will overflow at 2038-01-19 03:14:08 on 32-bit systems. We call this "2038 safety" issue. As part of addressing 2038 saftey for in-kernel uses, this patch creates no functional change in existing users, and converts rtc_tm_to_time_unsafe() to rtc_tm_to_time() in rtc_hctosys(). Signed-off-by: pang.xunlei <pang.xunlei@linaro.org> --- drivers/rtc/hctosys.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)