linux/kernel/time
Linus Torvalds a60ce761d9 Updates for the time/timer core subsystem:
- Harden the user space controllable hrtimer interfaces further to
     protect against unpriviledged DoS attempts by arming timers in the past.
 
   - Add per-capacity hierarchies to the timer migration code to prevent
     timer migration accross different capacity domains. This code has been
     disabled last minute as there is a pathological problem with SoCs which
     advertise a larger number of capacity domains. The problem is under
     investigation and the code won't be active before v7.3, but that turned
     out to be less intrusive than a full revert as it preserves the
     preparatory steps and allows people to work on the final resolution
 
   - Export time namespace functionality as a recent user can be built as a
     module.
 
   - Initialize the jiffies clocksource before using it. The recent
     hardening against time moving backward requires that the related
     members of struct clocksource have been initialized, otherwise it
     clamps the readout to 0, which makes time stand sill and causes boot
     delays.
 
   - Fix a more than twenty year old PID reference count leak in an error
     path of the POSIX CPU timer code.
 
   - The usual small fixes, improvements and cleanups all over the place.
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Merge tag 'timers-core-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

Pull timer core updates from Thomas Gleixner:
 "Updates for the time/timer core subsystem:

   - Harden the user space controllable hrtimer interfaces further to
     protect against unpriviledged DoS attempts by arming timers in the
     past.

   - Add per-capacity hierarchies to the timer migration code to prevent
     timer migration accross different capacity domains. This code has
     been disabled last minute as there is a pathological problem with
     SoCs which advertise a larger number of capacity domains. The
     problem is under investigation and the code won't be active before
     v7.3, but that turned out to be less intrusive than a full revert
     as it preserves the preparatory steps and allows people to work on
     the final resolution

   - Export time namespace functionality as a recent user can be built
     as a module.

   - Initialize the jiffies clocksource before using it. The recent
     hardening against time moving backward requires that the related
     members of struct clocksource have been initialized, otherwise it
     clamps the readout to 0, which makes time stand sill and causes
     boot delays.

   - Fix a more than twenty year old PID reference count leak in an
     error path of the POSIX CPU timer code.

   - The usual small fixes, improvements and cleanups all over the
     place"

* tag 'timers-core-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: (31 commits)
  posix-cpu-timers: Fix pid refcount leak in do_cpu_nanosleep() error path
  time/jiffies: Register jiffies clocksource before usage
  timers/migration: Temporarily disable per capacity hierarchies
  timers/migration: Turn tmigr_hierarchy level_list into a flexible array
  timers/migration: Deactivate per-capacity hierarchies under nohz_full
  timers/migration: Fix hotplug migrator selection target on asymetric capacity machines
  ntsync: Honour caller's time namespace for absolute MONOTONIC timeouts
  time/namespace: Export init_time_ns and do_timens_ktime_to_host()
  timers/migration: Update stale @online doc to @available
  timers: Fix flseep() typo in kernel-doc comment
  hrtimer: Fix the bogus return type of __hrtimer_start_range_ns()
  hrtimer: Return ktime_t from hrtimer_get_next_event()/hrtimer_next_event_without()
  clocksource: Clean up clocksource_update_freq() functions
  alarmtimer: Remove stale return description from alarm_handle_timer()
  selftests/posix_timers: Use CLOCK_THREAD_CPUTIME_ID for ITIMER_PROF measurements
  scripts/timers: Add timer_migration_tree.py
  timers/migration: Handle capacity in connect tracepoints
  timers/migration: Split per-capacity hierarchies
  timers/migration: Track CPUs in a hierarchy
  timers/migration: Abstract out hierarchy to prepare for CPU capacity awareness
  ...
2026-06-15 13:39:12 +05:30
..
.kunitconfig time/kunit: Add .kunitconfig 2026-02-24 08:41:51 +01:00
alarmtimer.c alarmtimer: Remove stale return description from alarm_handle_timer() 2026-05-06 08:33:08 +02:00
clockevents.c clockevents: Fix duplicate type specifier in stub function parameter 2026-06-02 21:07:55 +02:00
clocksource-wdtest.c clocksource: Rewrite watchdog code completely 2026-03-20 13:36:32 +01:00
clocksource.c Updates for the time/timer core subsystem: 2026-06-15 13:39:12 +05:30
hrtimer.c hrtimer: Fix the bogus return type of __hrtimer_start_range_ns() 2026-05-13 22:41:12 +02:00
itimer.c timers/itimer: Avoid direct access to hrtimer clockbase 2025-09-09 12:27:17 +02:00
jiffies.c time/jiffies: Register jiffies clocksource before usage 2026-06-13 15:22:40 +02:00
Kconfig Update to the VDSO subsystem: 2026-04-14 10:53:44 -07:00
Makefile timens: Remove dependency on the vDSO 2026-03-26 15:44:23 +01:00
namespace_internal.h timens: Remove dependency on the vDSO 2026-03-26 15:44:23 +01:00
namespace_vdso.c mm.git review status for linus..mm-stable 2026-04-15 12:59:16 -07:00
namespace.c time/namespace: Export init_time_ns and do_timens_ktime_to_host() 2026-06-02 21:05:36 +02:00
ntp_internal.h ntp: Rename __do_adjtimex() to ntp_adjtimex() 2025-06-19 14:28:23 +02:00
ntp.c ntp: Use ktime_get_ntp_seconds() 2025-06-19 14:28:24 +02:00
posix-clock.c Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
posix-cpu-timers.c posix-cpu-timers: Fix pid refcount leak in do_cpu_nanosleep() error path 2026-06-13 16:16:02 +02:00
posix-stubs.c
posix-timers.c posix-timers: Switch to hrtimer_start_expires_user() 2026-05-01 21:36:12 +02:00
posix-timers.h posix-timers: Expand timer_[re]arm() callbacks with a boolean return value 2026-05-01 21:36:11 +02:00
sched_clock.c time/sched_clock: Use ACCESS_PRIVATE() to evaluate hrtimer::function 2026-01-13 18:08:57 +01:00
sleep_timeout.c treewide, timers: Rename from_timer() to timer_container_of() 2025-06-08 09:07:37 +02:00
test_udelay.c time: Add MODULE_DESCRIPTION() to time test modules 2024-06-03 11:18:50 +02:00
tick-broadcast-hrtimer.c clockevents: Remove redundant CLOCK_EVT_FEAT_KTIME 2026-02-27 16:40:06 +01:00
tick-broadcast.c clockevents: Add missing resets of the next_event_forced flag 2026-04-16 21:22:04 +02:00
tick-common.c clockevents: Prevent timer interrupt starvation 2026-04-10 22:45:38 +02:00
tick-internal.h cpufreq: ondemand: Simplify idle cputime granularity test 2026-01-28 22:24:58 +01:00
tick-legacy.c
tick-oneshot.c treewide: Update email address 2026-01-11 06:09:11 -10:00
tick-sched.c hrtimer: Return ktime_t from hrtimer_get_next_event()/hrtimer_next_event_without() 2026-05-06 08:33:09 +02:00
tick-sched.h tick/sched: Fix struct tick_sched doc warnings 2024-04-01 10:36:35 +02:00
time_test.c time/kunit: Document handling of negative years of is_leap() 2026-02-02 12:37:54 +01:00
time.c time: Fix off-by-one in settimeofday() usec validation 2026-06-02 21:07:55 +02:00
timeconst.bc
timeconv.c
timecounter.c time/timecounter: Inline timecounter_cyc2time() 2025-12-15 20:16:49 +01:00
timekeeping_debug.c timekeeping: Add percpu counter for tracking floor swap events 2024-10-10 10:20:46 +02:00
timekeeping_internal.h timekeeping: Provide ktime_get_ntp_seconds() 2025-06-19 14:28:23 +02:00
timekeeping.c Linux 7.0-rc4 2026-03-21 08:02:36 +01:00
timekeeping.h timekeeping: Provide infrastructure for coupled clockevents 2026-02-27 16:40:08 +01:00
timer_list.c timer_list: Print offset as signed integer 2026-03-12 12:15:54 +01:00
timer_migration.c Updates for the time/timer core subsystem: 2026-06-15 13:39:12 +05:30
timer_migration.h timers/migration: Turn tmigr_hierarchy level_list into a flexible array 2026-06-02 21:34:03 +02:00
timer.c hrtimer: Return ktime_t from hrtimer_get_next_event()/hrtimer_next_event_without() 2026-05-06 08:33:09 +02:00
vsyscall.c vdso/vsyscall: Avoid slow division loop in auxiliary clock update 2025-09-03 11:55:11 +02:00