Fix an issue with the 32-bit range error path in `rtc_hctosys' where no
error code is set and consequently the successful preceding call result
from `rtc_read_time' is propagated to `rtc_hctosys_ret'. This in turn
makes any subsequent call to `hctosys_show' incorrectly report in sysfs
that the system time has been set from this RTC while it has not.
Set the error to ERANGE then if we can't express the result due to an
overflow.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Fixes: b3a5ac42ab ("rtc: hctosys: Ensure system time doesn't overflow time_t")
Cc: stable@vger.kernel.org # 4.17+
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
On 32bit platforms, time_t is still a signed 32bit long. If it is
overflowed, userspace and the kernel cant agree on the current system time.
This causes multiple issues, in particular with systemd:
https://github.com/systemd/systemd/issues/1143
A good workaround is to simply avoid using hctosys which is something I
greatly encourage as the time is better set by userspace.
However, many distribution enable it and use systemd which is rendering the
system unusable in case the RTC holds a date after 2038 (and more so after
2106). Many drivers have workaround for this case and they should be
eliminated so there is only one place left to fix when userspace is able to
cope with dates after the 31bit overflow.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Use function name in the error log instead of __FILE__.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When using device trees on the ARM platform, it is not certain at compile
time whether or not the system will have a RTC.
If one enables CONFIG_HCTOSYS just in case the system booted has a RTC,
and it turns out not to be, this will result in a big fat "unable to open
rtc device" error being printed to console, even when "quiet" is set in
the kernel cmdline.
Fix this by outputting the message with loglevel info instead.
Signed-off-by: Floris Bos <bos@je-eigen-domein.nl>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rtc_read_time() has already judged valid tm by rtc_valid_tm(),
so just remove it.
Cc: pang.xunlei <pang.xunlei@linaro.org>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
rtc_hctosys() has a number of y2038 issues.
This patch resolves them by:
- Replace rtc_tm_to_time() with y2038-safe rtc_tm_to_time64()
- Replace do_settimeofday() with y2038-safe do_settimeofday64()
After this patch, it should not have any remaining y2038 issues.
Cc: pang.xunlei <pang.xunlei@linaro.org>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Without this patch /sys/class/rtc/$CONFIG_RTC_HCTOSYS_DEVICE/hctosys
contains a 1 (meaning "This rtc was used to initialize the system
clock") even if setting the time by do_settimeofday() at bootup failed.
The RTC can also be used to set the clock on resume, if it did 1,
otherwise 0. Previously there was no indication if the RTC was used
to set the clock in resume.
This uses only CONFIG_RTC_HCTOSYS_DEVICE for conditional compilation
instead of it and CONFIG_RTC_HCTOSYS to be more consistent.
rtc_hctosys_ret was moved to class.c so class.c no longer depends on
hctosys.c.
[sfr@canb.auug.org.au: fix build]
Signed-off-by: David Fries <David@Fries.net>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Without this patch /sys/class/rtc/$CONFIG_RTC_HCTOSYS_DEVICE/hctosys
contains a 1 (meaning "This rtc was used to initialize the system clock")
even if reading the time at bootup failed.
Moreover change error handling in rtc_hctosys() to use goto and so reduce
the indention level.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Paul Gortmaker <p_gortmaker@yahoo.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The RTC "hctosys" mechanism expects that RTC clock will use UTC, not local
time (e.g. PST). Say so in Kconfig and in the kernel message.
(Strictly speaking, the RTC clock should be tracking the POSIX epoch. That's
not worth going into here. Goofing timezones means clocks are wrong by many
hours; the POSIX-v-UTC differences just cost seconds.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes class_device from the programming interface that the RTC
framework exposes to the rest of the kernel. Now an rtc_device is passed,
which is more type-safe and streamlines all the relevant code.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-By: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the basic RTC subsystem infrastructure to the kernel.
rtc/class.c - registration facilities for RTC drivers
rtc/interface.c - kernel/rtc interface functions
rtc/hctosys.c - snippet of code that copies hw clock to sw clock
at bootup, if configured to do so.
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
