clock_nanosleep() accepts absolute values of expiration time when the
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace and has to be converted to the host's time.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-16-dima@arista.com
Adjust monotonic and boottime clocks with per-timens offsets. As the
result a process inside time namespace will see timers and clocks corrected
to offsets that were set when the namespace was created
Note that applications usually go through vDSO to get time, which is not
yet adjusted. Further changes will complete time namespace virtualisation
with vDSO support.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-12-dima@arista.com
The callsite in common_timer_get() has already a comment:
/*
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
kc->clock_get(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-10-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
Wire up alarm bases with get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-9-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a tasks time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
struct alarm_base needs to follow the same naming convention, so rename
.gettime() callback into get_ktime() as a preparation for introducing
get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-8-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format in (struct k_clock).
As a preparation ground for introducing clock_get_ktime(), the original
callback clock_get() was renamed into clock_get_timespec().
Reflect the renaming into the callback implementations.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-7-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format, rather than in (struct timespec).
Rename the clock_get() callback to clock_get_timespec() as a preparation
for introducing clock_get_ktime().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-6-dima@arista.com
- Rework the main suspend-to-idle control flow to avoid repeating
"noirq" device resume and suspend operations in case of spurious
wakeups from the ACPI EC and decouple the ACPI EC wakeups support
from the LPS0 _DSM support (Rafael Wysocki).
- Extend the wakeup sources framework to expose wakeup sources as
device objects in sysfs (Tri Vo, Stephen Boyd).
- Expose system suspend statistics in sysfs (Kalesh Singh).
- Introduce a new haltpoll cpuidle driver and a new matching
governor for virtualized guests wanting to do guest-side polling
in the idle loop (Marcelo Tosatti, Joao Martins, Wanpeng Li,
Stephen Rothwell).
- Fix the menu and teo cpuidle governors to allow the scheduler tick
to be stopped if PM QoS is used to limit the CPU idle state exit
latency in some cases (Rafael Wysocki).
- Increase the resolution of the play_idle() argument to microseconds
for more fine-grained injection of CPU idle cycles (Daniel Lezcano).
- Switch over some users of cpuidle notifiers to the new QoS-based
frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY
policy notifier events (Viresh Kumar).
- Add new cpufreq driver based on nvmem for sun50i (Yangtao Li).
- Add support for MT8183 and MT8516 to the mediatek cpufreq driver
(Andrew-sh.Cheng, Fabien Parent).
- Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson
Huang).
- Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz).
- Update the qcom cpufreq driver (among other things, to make it
easier to extend and to use kryo cpufreq for other nvmem-based
SoCs) and add qcs404 support to it (Niklas Cassel, Douglas
RAILLARD, Sibi Sankar, Sricharan R).
- Fix assorted issues and make assorted minor improvements in the
cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli,
Gustavo Silva, Hariprasad Kelam).
- Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd
Bergmann).
- Add new Exynos PPMU events to devfreq events and extend that
mechanism (Lukasz Luba).
- Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny).
- Improve devfreq documentation and governor code, fix spelling
typos in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard
Crestez, MyungJoo Ham, Gaël PORTAY).
- Add regulators enable and disable to the OPP (operating performance
points) framework (Kamil Konieczny).
- Update the OPP framework to support multiple opp-suspend properties
(Anson Huang).
- Fix assorted issues and make assorted minor improvements in the OPP
code (Niklas Cassel, Viresh Kumar, Yue Hu).
- Clean up the generic power domains (genpd) framework (Ulf Hansson).
- Clean up assorted pieces of power management code and documentation
(Akinobu Mita, Amit Kucheria, Chuhong Yuan).
- Update the pm-graph tool to version 5.5 including multiple fixes
and improvements (Todd Brandt).
- Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven,
Sébastien Szymanski).
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Merge tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These include a rework of the main suspend-to-idle code flow (related
to the handling of spurious wakeups), a switch over of several users
of cpufreq notifiers to QoS-based limits, a new devfreq driver for
Tegra20, a new cpuidle driver and governor for virtualized guests, an
extension of the wakeup sources framework to expose wakeup sources as
device objects in sysfs, and more.
Specifics:
- Rework the main suspend-to-idle control flow to avoid repeating
"noirq" device resume and suspend operations in case of spurious
wakeups from the ACPI EC and decouple the ACPI EC wakeups support
from the LPS0 _DSM support (Rafael Wysocki).
- Extend the wakeup sources framework to expose wakeup sources as
device objects in sysfs (Tri Vo, Stephen Boyd).
- Expose system suspend statistics in sysfs (Kalesh Singh).
- Introduce a new haltpoll cpuidle driver and a new matching governor
for virtualized guests wanting to do guest-side polling in the idle
loop (Marcelo Tosatti, Joao Martins, Wanpeng Li, Stephen Rothwell).
- Fix the menu and teo cpuidle governors to allow the scheduler tick
to be stopped if PM QoS is used to limit the CPU idle state exit
latency in some cases (Rafael Wysocki).
- Increase the resolution of the play_idle() argument to microseconds
for more fine-grained injection of CPU idle cycles (Daniel
Lezcano).
- Switch over some users of cpuidle notifiers to the new QoS-based
frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY
policy notifier events (Viresh Kumar).
- Add new cpufreq driver based on nvmem for sun50i (Yangtao Li).
- Add support for MT8183 and MT8516 to the mediatek cpufreq driver
(Andrew-sh.Cheng, Fabien Parent).
- Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson
Huang).
- Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz).
- Update the qcom cpufreq driver (among other things, to make it
easier to extend and to use kryo cpufreq for other nvmem-based
SoCs) and add qcs404 support to it (Niklas Cassel, Douglas
RAILLARD, Sibi Sankar, Sricharan R).
- Fix assorted issues and make assorted minor improvements in the
cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli,
Gustavo Silva, Hariprasad Kelam).
- Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd
Bergmann).
- Add new Exynos PPMU events to devfreq events and extend that
mechanism (Lukasz Luba).
- Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny).
- Improve devfreq documentation and governor code, fix spelling typos
in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard Crestez,
MyungJoo Ham, Gaël PORTAY).
- Add regulators enable and disable to the OPP (operating performance
points) framework (Kamil Konieczny).
- Update the OPP framework to support multiple opp-suspend properties
(Anson Huang).
- Fix assorted issues and make assorted minor improvements in the OPP
code (Niklas Cassel, Viresh Kumar, Yue Hu).
- Clean up the generic power domains (genpd) framework (Ulf Hansson).
- Clean up assorted pieces of power management code and documentation
(Akinobu Mita, Amit Kucheria, Chuhong Yuan).
- Update the pm-graph tool to version 5.5 including multiple fixes
and improvements (Todd Brandt).
- Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven,
Sébastien Szymanski)"
* tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (126 commits)
cpuidle-haltpoll: Enable kvm guest polling when dedicated physical CPUs are available
cpuidle-haltpoll: do not set an owner to allow modunload
cpuidle-haltpoll: return -ENODEV on modinit failure
cpuidle-haltpoll: set haltpoll as preferred governor
cpuidle: allow governor switch on cpuidle_register_driver()
PM: runtime: Documentation: add runtime_status ABI document
pm-graph: make setVal unbuffered again for python2 and python3
powercap: idle_inject: Use higher resolution for idle injection
cpuidle: play_idle: Increase the resolution to usec
cpuidle-haltpoll: vcpu hotplug support
cpufreq: Add qcs404 to cpufreq-dt-platdev blacklist
cpufreq: qcom: Add support for qcs404 on nvmem driver
cpufreq: qcom: Refactor the driver to make it easier to extend
cpufreq: qcom: Re-organise kryo cpufreq to use it for other nvmem based qcom socs
dt-bindings: opp: Add qcom-opp bindings with properties needed for CPR
dt-bindings: opp: qcom-nvmem: Support pstates provided by a power domain
Documentation: cpufreq: Update policy notifier documentation
cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events
PM / Domains: Verify PM domain type in dev_pm_genpd_set_performance_state()
PM / Domains: Simplify genpd_lookup_dev()
...
Pull core timer updates from Thomas Gleixner:
"Timers and timekeeping updates:
- A large overhaul of the posix CPU timer code which is a preparation
for moving the CPU timer expiry out into task work so it can be
properly accounted on the task/process.
An update to the bogus permission checks will come later during the
merge window as feedback was not complete before heading of for
travel.
- Switch the timerqueue code to use cached rbtrees and get rid of the
homebrewn caching of the leftmost node.
- Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a
single function
- Implement the separation of hrtimers to be forced to expire in hard
interrupt context even when PREEMPT_RT is enabled and mark the
affected timers accordingly.
- Implement a mechanism for hrtimers and the timer wheel to protect
RT against priority inversion and live lock issues when a (hr)timer
which should be canceled is currently executing the callback.
Instead of infinitely spinning, the task which tries to cancel the
timer blocks on a per cpu base expiry lock which is held and
released by the (hr)timer expiry code.
- Enable the Hyper-V TSC page based sched_clock for Hyper-V guests
resulting in faster access to timekeeping functions.
- Updates to various clocksource/clockevent drivers and their device
tree bindings.
- The usual small improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
posix-cpu-timers: Fix permission check regression
posix-cpu-timers: Always clear head pointer on dequeue
hrtimer: Add a missing bracket and hide `migration_base' on !SMP
posix-cpu-timers: Make expiry_active check actually work correctly
posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build
tick: Mark sched_timer to expire in hard interrupt context
hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD
x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n
posix-cpu-timers: Utilize timerqueue for storage
posix-cpu-timers: Move state tracking to struct posix_cputimers
posix-cpu-timers: Deduplicate rlimit handling
posix-cpu-timers: Remove pointless comparisons
posix-cpu-timers: Get rid of 64bit divisions
posix-cpu-timers: Consolidate timer expiry further
posix-cpu-timers: Get rid of zero checks
rlimit: Rewrite non-sensical RLIMIT_CPU comment
posix-cpu-timers: Respect INFINITY for hard RTTIME limit
posix-cpu-timers: Switch thread group sampling to array
posix-cpu-timers: Restructure expiry array
posix-cpu-timers: Remove cputime_expires
...
ENOTSUPP is not supposed to be returned to userspace. This was found on an
OpenPower machine, where the RTC does not support set_alarm.
On that system, a clock_nanosleep(CLOCK_REALTIME_ALARM, ...) results in
"524 Unknown error 524"
Replace it with EOPNOTSUPP which results in the expected "95 Operation not
supported" error.
Fixes: 1c6b39ad3f (alarmtimers: Return -ENOTSUPP if no RTC device is present)
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190903171802.28314-1-cascardo@canonical.com
Add an ID and a device pointer to 'struct wakeup_source'. Use them to to
expose wakeup sources statistics in sysfs under
/sys/class/wakeup/wakeup<ID>/*.
Co-developed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Tri Vo <trong@android.com>
Tested-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Posix timer delete retry loops are affected by the same priority inversion
and live lock issues as the other timers.
Provide a RT specific synchronization function which keeps a reference to
the timer by holding rcu read lock to prevent the timer from being freed,
dropping the timer lock and invoking the timer specific wait function via a
new callback.
This does not yet cover posix CPU timers because they need more special
treatment on PREEMPT_RT.
[ This is folded into the original attempt which did not use a callback. ]
Originally-by: Anna-Maria Gleixenr <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.656864506@linutronix.de
Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.
[ tglx: Split out of combo patch ]
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.508744705@linutronix.de
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: d653d8457c ("alarmtimer: Implement remaining callback")
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190408041542.26338-1-avagin@gmail.com
The SPDX identifier defines the license of the files already. No need for
the boilerplates.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20181031182253.132458951@linutronix.de
Update the time(r) core files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of the
full boiler plate text.
This work is based on a script and data from Philippe Ombredanne, Kate
Stewart and myself. The data has been created with two independent license
scanners and manual inspection.
The following files do not contain any direct license information and have
been omitted from the big initial SPDX changes:
timeconst.bc: The .bc files were not touched
time.c, timer.c, timekeeping.c: Licence was deduced from EXPORT_SYMBOL_GPL
As those files do not contain direct license references they fall under the
project license, i.e. GPL V2 only.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20181031182252.879109557@linutronix.de
Air Icy reported:
UBSAN: Undefined behaviour in kernel/time/alarmtimer.c:811:7
signed integer overflow:
1529859276030040771 + 9223372036854775807 cannot be represented in type 'long long int'
Call Trace:
alarm_timer_nsleep+0x44c/0x510 kernel/time/alarmtimer.c:811
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1235 [inline]
__se_sys_clock_nanosleep kernel/time/posix-timers.c:1213 [inline]
__x64_sys_clock_nanosleep+0x326/0x4e0 kernel/time/posix-timers.c:1213
do_syscall_64+0xb8/0x3a0 arch/x86/entry/common.c:290
alarm_timer_nsleep() uses ktime_add() to add the current time and the
relative expiry value. ktime_add() has no sanity checks so the addition
can overflow when the relative timeout is large enough.
Use ktime_add_safe() which has the necessary sanity checks in place and
limits the result to the valid range.
Fixes: 9a7adcf5c6 ("timers: Posix interface for alarm-timers")
Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1807020926360.1595@nanos.tec.linutronix.de
The posix timer ti_overrun handling is broken because the forwarding
functions can return a huge number of overruns which does not fit in an
int. As a consequence timer_getoverrun(2) and siginfo::si_overrun can turn
into random number generators.
As a first step to address that let the timer_forward() callbacks return
the full 64 bit value.
Cast it to (int) temporarily until k_itimer::ti_overrun is converted to
64bit and the conversion to user space visible values is sanitized.
Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Link: https://lkml.kernel.org/r/20180626132704.922098090@linutronix.de
syszbot reported the following debugobjects splat:
ODEBUG: object is on stack, but not annotated
WARNING: CPU: 0 PID: 4185 at lib/debugobjects.c:328
RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:327 [inline]
debug_object_init+0x17/0x20 lib/debugobjects.c:391
debug_hrtimer_init kernel/time/hrtimer.c:410 [inline]
debug_init kernel/time/hrtimer.c:458 [inline]
hrtimer_init+0x8c/0x410 kernel/time/hrtimer.c:1259
alarm_init kernel/time/alarmtimer.c:339 [inline]
alarm_timer_nsleep+0x164/0x4d0 kernel/time/alarmtimer.c:787
SYSC_clock_nanosleep kernel/time/posix-timers.c:1226 [inline]
SyS_clock_nanosleep+0x235/0x330 kernel/time/posix-timers.c:1204
do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x42/0xb7
This happens because the hrtimer for the alarm nanosleep is on stack, but
the code does not use the proper debug objects initialization.
Split out the code for the allocated use cases and invoke
hrtimer_init_on_stack() for the nanosleep related functions.
Reported-by: syzbot+a3e0726462b2e346a31d@syzkaller.appspotmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: syzkaller-bugs@googlegroups.com
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1803261528270.1585@nanos.tec.linutronix.de
When registering the rtc device to be used to handle alarm timers,
get_device is used to ensure the device doesn't go away but the module can
still be unloaded.
Call try_module_get to ensure the rtc driver will not go away.
Reported-and-tested-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Link: http://lkml.kernel.org/r/20170820220146.30969-1-alexandre.belloni@free-electrons.com
Currently the alarmtimer registers a wake-up source unconditionally,
regardless of the system having a (wake-up capable) RTC or not.
Hence the alarmtimer will always show up in
/sys/kernel/debug/wakeup_sources, even if it is not available, and thus
cannot be a wake-up source.
To fix this, postpone registration until a wake-up capable RTC device is
added.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Usage of these apis and their compat versions makes
the syscalls: clock_nanosleep and nanosleep and
their compat implementations simpler.
This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
No nanosleep implementation modifies the rqtp argument. Mark is const.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Turn restart_block.nanosleep.{rmtp,compat_rmtp} into a tagged union (kind =
1 -> native, kind = 2 -> compat, kind = 0 -> nothing) and make the places
doing actual copyout handle compat as well as native (that will become a
helper in the next commit). Result: compat wrappers, messing with
reassignments, etc. are gone.
[ tglx: Folded in a variant of Peter Zijlstras enum patch ]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-6-viro@ZenIV.linux.org.uk
... instead of doing that in every ->nsleep() instance
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-5-viro@ZenIV.linux.org.uk
The alarmtimer nanosleep() implementation can be simplified by moving the
copy out of the remaining time to alarmtimer_do_nsleep() which is shared
between the real nanosleep function and the restart function.
The pointer to the timespec64 which is updated has to be stored in the
restart block anyway. Instead of storing it only in the restart case, store
it before calling alarmtimer_do_nsleep() and copy the remaining time in the
signal exit path.
[ tglx: Added changelog ]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-2-viro@ZenIV.linux.org.uk
All required callbacks are in place. Switch the alarm timer based posix
interval timer callbacks to the common implementation and remove the
incorrect private implementation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.825471962@linutronix.de
Preparatory change to utilize the common posix timer mechanisms.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.747567162@linutronix.de
Preparatory change to utilize the common posix timer mechanisms.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.670026824@linutronix.de
Preparatory change to utilize the common posix timer mechanisms.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.592676753@linutronix.de
Preparatory change to utilize the common posix timer mechanisms.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.513694229@linutronix.de
Preparatory change to utilize the common posix timer mechanisms.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211657.434598989@linutronix.de
Preparatory patch to unify the alarm timer and hrtimer based posix interval
timer handling.
The interval is used as a criteria for rearming decisions so moving it out
of the clock specific data structures allows later unification.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211656.563922908@linutronix.de
None of these declarations is required outside of kernel/time. Move them to
an internal header.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20170530211656.394803853@linutronix.de
Having a IF_ENABLED(CONFIG_POSIX_TIMERS) inside of a
#ifdef CONFIG_POSIX_TIMERS section is pointless.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211655.975218056@linutronix.de
The alarmtimer code has another source of potentially rearming itself too
fast. Interval timers with a very samll interval have a similar CPU hog
effect as the previously fixed overflow issue.
The reason is that alarmtimers do not implement the normal protection
against this kind of problem which the other posix timer use:
timer expires -> queue signal -> deliver signal -> rearm timer
This scheme brings the rearming under scheduler control and prevents
permanently firing timers which hog the CPU.
Bringing this scheme to the alarm timer code is a major overhaul because it
lacks all the necessary mechanisms completely.
So for a quick fix limit the interval to one jiffie. This is not
problematic in practice as alarmtimers are usually backed by an RTC for
suspend which have 1 second resolution. It could be therefor argued that
the resolution of this clock should be set to 1 second in general, but
that's outside the scope of this fix.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kostya Serebryany <kcc@google.com>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170530211655.896767100@linutronix.de
Andrey reported a alartimer related RCU stall while fuzzing the kernel with
syzkaller.
The reason for this is an overflow in ktime_add() which brings the
resulting time into negative space and causes immediate expiry of the
timer. The following rearm with a small interval does not bring the timer
back into positive space due to the same issue.
This results in a permanent firing alarmtimer which hogs the CPU.
Use ktime_add_safe() instead which detects the overflow and clamps the
result to KTIME_SEC_MAX.
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kostya Serebryany <kcc@google.com>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170530211655.802921648@linutronix.de
Some freezer related variables are only used when either CONFIG_POSIX_TIMER
or CONFIG_RTC_CLASS are enabled. Hide them when both are off.
Fixes: d3ba5a9a34 ("posix-timers: Make posix_clocks immutable")
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Helwig <hch@lst.de>
There are no more modular users providing a posix clock. The register
function is now pointless so the posix clock array can be initialized
statically at compile time and the array including the various k_clock
structs can be marked 'const'.
Inspired by changes in the Grsecurity patch set, but done proper.
[ tglx: Massaged changelog and fixed the POSIX_TIMER=n case ]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Link: http://lkml.kernel.org/r/20170526090311.3377-3-hch@lst.de
struct timespec is not y2038 safe on 32 bit machines. Replace uses of
struct timespec with struct timespec64 in the kernel.
The syscall interfaces themselves will be changed in a separate series.
Note that the restart_block parameter for nanosleep has also been left
unchanged and will be part of syscall series noted above.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-8-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
struct timespec is not y2038 safe on 32 bit machines. Replace uses of
struct timespec with struct timespec64 in the kernel.
struct itimerspec internally uses struct timespec. Use struct itimerspec64
which uses struct timespec64.
The syscall interfaces themselves will be changed in a separate series.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-7-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
struct timespec is not y2038 safe on 32 bit machines. Replace uses of
struct timespec with struct timespec64 in the kernel. The syscall
interfaces themselves will be changed in a separate series.
The clock_getres() interface has also been changed to use timespec64 even
though this particular interface is not affected by the y2038 problem. This
helps verification for internal kernel code for y2038 readiness by getting
rid of time_t/ timeval/ timespec completely.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-5-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/debug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.
Get rid of the union and just keep ktime_t as simple typedef of type s64.
The conversion was done with coccinelle and some manual mopping up.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
