<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel/time, branch v5.1.10</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.1.10</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.1.10'/>
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<updated>2019-06-15T09:52:55Z</updated>
<entry>
<title>ntp: Allow TAI-UTC offset to be set to zero</title>
<updated>2019-06-15T09:52:55Z</updated>
<author>
<name>Miroslav Lichvar</name>
<email>mlichvar@redhat.com</email>
</author>
<published>2019-04-17T08:48:33Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=01e0054e3e0d3e00095b3999829c423a7f911363'/>
<id>urn:sha1:01e0054e3e0d3e00095b3999829c423a7f911363</id>
<content type='text'>
[ Upstream commit fdc6bae940ee9eb869e493990540098b8c0fd6ab ]

The ADJ_TAI adjtimex mode sets the TAI-UTC offset of the system clock.
It is typically set by NTP/PTP implementations and it is automatically
updated by the kernel on leap seconds. The initial value is zero (which
applications may interpret as unknown), but this value cannot be set by
adjtimex. This limitation seems to go back to the original "nanokernel"
implementation by David Mills.

Change the ADJ_TAI check to accept zero as a valid TAI-UTC offset in
order to allow setting it back to the initial value.

Fixes: 153b5d054ac2 ("ntp: support for TAI")
Suggested-by: Ondrej Mosnacek &lt;omosnace@redhat.com&gt;
Signed-off-by: Miroslav Lichvar &lt;mlichvar@redhat.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Richard Cochran &lt;richardcochran@gmail.com&gt;
Cc: Prarit Bhargava &lt;prarit@redhat.com&gt;
Link: https://lkml.kernel.org/r/20190417084833.7401-1-mlichvar@redhat.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>timekeeping: Force upper bound for setting CLOCK_REALTIME</title>
<updated>2019-05-31T13:43:46Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-03-23T10:36:19Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=5e04fcbab4b417ac1110ec917f653d7eb38fd056'/>
<id>urn:sha1:5e04fcbab4b417ac1110ec917f653d7eb38fd056</id>
<content type='text'>
[ Upstream commit 7a8e61f8478639072d402a26789055a4a4de8f77 ]

Several people reported testing failures after setting CLOCK_REALTIME close
to the limits of the kernel internal representation in nanoseconds,
i.e. year 2262.

The failures are exposed in subsequent operations, i.e. when arming timers
or when the advancing CLOCK_MONOTONIC makes the calculation of
CLOCK_REALTIME overflow into negative space.

Now people start to paper over the underlying problem by clamping
calculations to the valid range, but that's just wrong because such
workarounds will prevent detection of real issues as well.

It is reasonable to force an upper bound for the various methods of setting
CLOCK_REALTIME. Year 2262 is the absolute upper bound. Assume a maximum
uptime of 30 years which is plenty enough even for esoteric embedded
systems. That results in an upper bound of year 2232 for setting the time.

Once that limit is reached in reality this limit is only a small part of
the problem space. But until then this stops people from trying to paper
over the problem at the wrong places.

Reported-by: Xiongfeng Wang &lt;wangxiongfeng2@huawei.com&gt;
Reported-by: Hongbo Yao &lt;yaohongbo@huawei.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Stephen Boyd &lt;sboyd@kernel.org&gt;
Cc: Miroslav Lichvar &lt;mlichvar@redhat.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Richard Cochran &lt;richardcochran@gmail.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1903231125480.2157@nanos.tec.linutronix.de
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>timers/sched_clock: Prevent generic sched_clock wrap caused by tick_freeze()</title>
<updated>2019-04-18T12:34:53Z</updated>
<author>
<name>Chang-An Chen</name>
<email>chang-an.chen@mediatek.com</email>
</author>
<published>2019-03-29T02:59:09Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=3f2552f7e9c5abef2775c53f7af66532f8bf65bc'/>
<id>urn:sha1:3f2552f7e9c5abef2775c53f7af66532f8bf65bc</id>
<content type='text'>
tick_freeze() introduced by suspend-to-idle in commit 124cf9117c5f ("PM /
sleep: Make it possible to quiesce timers during suspend-to-idle") uses
timekeeping_suspend() instead of syscore_suspend() during
suspend-to-idle. As a consequence generic sched_clock will keep going
because sched_clock_suspend() and sched_clock_resume() are not invoked
during suspend-to-idle which can result in a generic sched_clock wrap.

On a ARM system with suspend-to-idle enabled, sched_clock is registered
as "56 bits at 13MHz, resolution 76ns, wraps every 4398046511101ns", which
means the real wrapping duration is 8796093022202ns.

[  134.551779] suspend-to-idle suspend (timekeeping_suspend())
[ 1204.912239] suspend-to-idle resume (timekeeping_resume())
......
[ 1206.912239] suspend-to-idle suspend (timekeeping_suspend())
[ 5880.502807] suspend-to-idle resume (timekeeping_resume())
......
[ 6000.403724] suspend-to-idle suspend (timekeeping_suspend())
[ 8035.753167] suspend-to-idle resume  (timekeeping_resume())
......
[ 8795.786684] (2)[321:charger_thread]......
[ 8795.788387] (2)[321:charger_thread]......
[    0.057226] (0)[0:swapper/0]......
[    0.061447] (2)[0:swapper/2]......

sched_clock was not stopped during suspend-to-idle, and sched_clock_poll
hrtimer was not expired because timekeeping_suspend() was invoked during
suspend-to-idle. It makes sched_clock wrap at kernel time 8796s.

To prevent this, invoke sched_clock_suspend() and sched_clock_resume() in
tick_freeze() together with timekeeping_suspend() and timekeeping_resume().

Fixes: 124cf9117c5f (PM / sleep: Make it possible to quiesce timers during suspend-to-idle)
Signed-off-by: Chang-An Chen &lt;chang-an.chen@mediatek.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Matthias Brugger &lt;matthias.bgg@gmail.com&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Corey Minyard &lt;cminyard@mvista.com&gt;
Cc: &lt;linux-mediatek@lists.infradead.org&gt;
Cc: &lt;linux-arm-kernel@lists.infradead.org&gt;
Cc: Stanley Chu &lt;stanley.chu@mediatek.com&gt;
Cc: &lt;kuohong.wang@mediatek.com&gt;
Cc: &lt;freddy.hsin@mediatek.com&gt;
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1553828349-8914-1-git-send-email-chang-an.chen@mediatek.com
</content>
</entry>
<entry>
<title>alarmtimer: Return correct remaining time</title>
<updated>2019-04-10T13:23:26Z</updated>
<author>
<name>Andrei Vagin</name>
<email>avagin@gmail.com</email>
</author>
<published>2019-04-08T04:15:42Z</published>
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<id>urn:sha1:07d7e12091f4ab869cc6a4bb276399057e73b0b3</id>
<content type='text'>
To calculate a remaining time, it's required to subtract the current time
from the expiration time. In alarm_timer_remaining() the arguments of
ktime_sub are swapped.

Fixes: d653d8457c76 ("alarmtimer: Implement remaining callback")
Signed-off-by: Andrei Vagin &lt;avagin@gmail.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Mukesh Ojha &lt;mojha@codeaurora.org&gt;
Cc: Stephen Boyd &lt;sboyd@kernel.org&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190408041542.26338-1-avagin@gmail.com

</content>
</entry>
<entry>
<title>time/jiffies: Make refined_jiffies static</title>
<updated>2019-03-22T12:38:26Z</updated>
<author>
<name>Valdis Kletnieks</name>
<email>valdis.kletnieks@vt.edu</email>
</author>
<published>2019-03-12T08:38:35Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e8750053d64a3317cbc15f8341f0f11ca751bfeb'/>
<id>urn:sha1:e8750053d64a3317cbc15f8341f0f11ca751bfeb</id>
<content type='text'>
sparse complains:

  CHECK   kernel/time/jiffies.c
kernel/time/jiffies.c:92:20: warning: symbol 'refined_jiffies' was not
			     	      declared. Should it be static?

Its only used in file scope. Make it static.

Signed-off-by: Valdis Kletnieks &lt;valdis.kletnieks@vt.edu&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lkml.kernel.org/r/32342.1552379915@turing-police

</content>
</entry>
<entry>
<title>Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2019-03-05T22:49:11Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-05T22:49:11Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=3717f613f48df0222311f974cf8a06c8a6c97bae'/>
<id>urn:sha1:3717f613f48df0222311f974cf8a06c8a6c97bae</id>
<content type='text'>
Pull RCU updates from Ingo Molnar:
 "The main RCU related changes in this cycle were:

   - Additional cleanups after RCU flavor consolidation

   - Grace-period forward-progress cleanups and improvements

   - Documentation updates

   - Miscellaneous fixes

   - spin_is_locked() conversions to lockdep

   - SPDX changes to RCU source and header files

   - SRCU updates

   - Torture-test updates, including nolibc updates and moving nolibc to
     tools/include"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
  locking/locktorture: Convert to SPDX license identifier
  linux/torture: Convert to SPDX license identifier
  torture: Convert to SPDX license identifier
  linux/srcu: Convert to SPDX license identifier
  linux/rcutree: Convert to SPDX license identifier
  linux/rcutiny: Convert to SPDX license identifier
  linux/rcu_sync: Convert to SPDX license identifier
  linux/rcu_segcblist: Convert to SPDX license identifier
  linux/rcupdate: Convert to SPDX license identifier
  linux/rcu_node_tree: Convert to SPDX license identifier
  rcu/update: Convert to SPDX license identifier
  rcu/tree: Convert to SPDX license identifier
  rcu/tiny: Convert to SPDX license identifier
  rcu/sync: Convert to SPDX license identifier
  rcu/srcu: Convert to SPDX license identifier
  rcu/rcutorture: Convert to SPDX license identifier
  rcu/rcu_segcblist: Convert to SPDX license identifier
  rcu/rcuperf: Convert to SPDX license identifier
  rcu/rcu.h: Convert to SPDX license identifier
  RCU/torture.txt: Remove section MODULE PARAMETERS
  ...
</content>
</entry>
<entry>
<title>Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2019-03-05T22:08:26Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-03-05T22:08:26Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b1b988a6a035212f5ea205155c49ce449beedee8'/>
<id>urn:sha1:b1b988a6a035212f5ea205155c49ce449beedee8</id>
<content type='text'>
Pull year 2038 updates from Thomas Gleixner:
 "Another round of changes to make the kernel ready for 2038. After lots
  of preparatory work this is the first set of syscalls which are 2038
  safe:

    403 clock_gettime64
    404 clock_settime64
    405 clock_adjtime64
    406 clock_getres_time64
    407 clock_nanosleep_time64
    408 timer_gettime64
    409 timer_settime64
    410 timerfd_gettime64
    411 timerfd_settime64
    412 utimensat_time64
    413 pselect6_time64
    414 ppoll_time64
    416 io_pgetevents_time64
    417 recvmmsg_time64
    418 mq_timedsend_time64
    419 mq_timedreceiv_time64
    420 semtimedop_time64
    421 rt_sigtimedwait_time64
    422 futex_time64
    423 sched_rr_get_interval_time64

  The syscall numbers are identical all over the architectures"

* 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  riscv: Use latest system call ABI
  checksyscalls: fix up mq_timedreceive and stat exceptions
  unicore32: Fix __ARCH_WANT_STAT64 definition
  asm-generic: Make time32 syscall numbers optional
  asm-generic: Drop getrlimit and setrlimit syscalls from default list
  32-bit userspace ABI: introduce ARCH_32BIT_OFF_T config option
  compat ABI: use non-compat openat and open_by_handle_at variants
  y2038: add 64-bit time_t syscalls to all 32-bit architectures
  y2038: rename old time and utime syscalls
  y2038: remove struct definition redirects
  y2038: use time32 syscall names on 32-bit
  syscalls: remove obsolete __IGNORE_ macros
  y2038: syscalls: rename y2038 compat syscalls
  x86/x32: use time64 versions of sigtimedwait and recvmmsg
  timex: change syscalls to use struct __kernel_timex
  timex: use __kernel_timex internally
  sparc64: add custom adjtimex/clock_adjtime functions
  time: fix sys_timer_settime prototype
  time: Add struct __kernel_timex
  time: make adjtime compat handling available for 32 bit
  ...
</content>
</entry>
<entry>
<title>Merge branch 'rcu-next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu</title>
<updated>2019-02-13T07:36:18Z</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2019-02-13T07:36:18Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=cae45e1c6c541283a1bd155aa7b0a57e353b4df4'/>
<id>urn:sha1:cae45e1c6c541283a1bd155aa7b0a57e353b4df4</id>
<content type='text'>
Pull the latest RCU tree from Paul E. McKenney:

 - Additional cleanups after RCU flavor consolidation
 - Grace-period forward-progress cleanups and improvements
 - Documentation updates
 - Miscellaneous fixes
 - spin_is_locked() conversions to lockdep
 - SPDX changes to RCU source and header files
 - SRCU updates
 - Torture-test updates, including nolibc updates and moving
   nolibc to tools/include

Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'y2038-new-syscalls' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground into timers/2038</title>
<updated>2019-02-10T20:24:43Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-02-10T19:50:32Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=41ea39101d6b84394fae0c12b702c4326aa71d17'/>
<id>urn:sha1:41ea39101d6b84394fae0c12b702c4326aa71d17</id>
<content type='text'>
Pull y2038 - time64 system calls from Arnd Bergmann:

This series finally gets us to the point of having system calls with 64-bit
time_t on all architectures, after a long time of incremental preparation
patches.

There was actually one conversion that I missed during the summer,
i.e. Deepa's timex series, which I now updated based the 5.0-rc1 changes
and review comments.

The following system calls are now added on all 32-bit architectures using
the same system call numbers:

403 clock_gettime64
404 clock_settime64
405 clock_adjtime64
406 clock_getres_time64
407 clock_nanosleep_time64
408 timer_gettime64
409 timer_settime64
410 timerfd_gettime64
411 timerfd_settime64
412 utimensat_time64
413 pselect6_time64
414 ppoll_time64
416 io_pgetevents_time64
417 recvmmsg_time64
418 mq_timedsend_time64
419 mq_timedreceiv_time64
420 semtimedop_time64
421 rt_sigtimedwait_time64
422 futex_time64
423 sched_rr_get_interval_time64

Each one of these corresponds directly to an existing system call that
includes a 'struct timespec' argument, or a structure containing a timespec
or (in case of clock_adjtime) timeval. Not included here are new versions
of getitimer/setitimer and getrusage/waitid, which are planned for the
future but only needed to make a consistent API rather than for correct
operation beyond y2038. These four system calls are based on 'timeval', and
it has not been finally decided what the replacement kernel interface will
use instead.

So far, I have done a lot of build testing across most architectures, which
has found a number of bugs. Runtime testing so far included testing LTP on
32-bit ARM with the existing system calls, to ensure we do not regress for
existing binaries, and a test with a 32-bit x86 build of LTP against a
modified version of the musl C library that has been adapted to the new
system call interface [3].  This library can be used for testing on all
architectures supported by musl-1.1.21, but it is not how the support is
getting integrated into the official musl release. Official musl support is
planned but will require more invasive changes to the library.

Link: https://lore.kernel.org/lkml/20190110162435.309262-1-arnd@arndb.de/T/
Link: https://lore.kernel.org/lkml/20190118161835.2259170-1-arnd@arndb.de/
Link: https://git.linaro.org/people/arnd/musl-y2038.git/ [2]
</content>
</entry>
<entry>
<title>y2038: rename old time and utime syscalls</title>
<updated>2019-02-06T23:13:28Z</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2019-01-06T22:45:29Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d33c577cccd0b3e5bb2425f85037f26714a59363'/>
<id>urn:sha1:d33c577cccd0b3e5bb2425f85037f26714a59363</id>
<content type='text'>
The time, stime, utime, utimes, and futimesat system calls are only
used on older architectures, and we do not provide y2038 safe variants
of them, as they are replaced by clock_gettime64, clock_settime64,
and utimensat_time64.

However, for consistency it seems better to have the 32-bit architectures
that still use them call the "time32" entry points (leaving the
traditional handlers for the 64-bit architectures), like we do for system
calls that now require two versions.

Note: We used to always define __ARCH_WANT_SYS_TIME and
__ARCH_WANT_SYS_UTIME and only set __ARCH_WANT_COMPAT_SYS_TIME and
__ARCH_WANT_SYS_UTIME32 for compat mode on 64-bit kernels. Now this is
reversed: only 64-bit architectures set __ARCH_WANT_SYS_TIME/UTIME, while
we need __ARCH_WANT_SYS_TIME32/UTIME32 for 32-bit architectures and compat
mode. The resulting asm/unistd.h changes look a bit counterintuitive.

This is only a cleanup patch and it should not change any behavior.

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
</entry>
</feed>
