Resolve conflict between this change in the upstream kernel:

  4c652a47722f ("rseq: Mark rseq_arm_slice_extension_timer() __always_inline")

... and this pending change in timers/core:

  0e98eb14814e ("entry: Prepare for deferred hrtimer rearming")

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Neither the array nor the offsets it is pointing to are meant to be
changed through the array.

Mark both the array and the values it points to as const.

Signed-off-by: Thomas Weißschuh (Schneider Electric) <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260311-hrtimer-cleanups-v1-5-095357392669@linutronix.de

In aux_clock_enable() the clocksource from tkr_raw is used to call
tk_setup_internals(). Do the same in tk_aux_update_clocksource().  While
the clocksources will be the same in any case, this is less confusing.

Signed-off-by: Thomas Weißschuh (Schneider Electric) <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260311-hrtimer-cleanups-v1-4-095357392669@linutronix.de

Nathan reported a boot failure after the coupled clocksource/event support
was enabled for the TSC deadline timer. It turns out that on the affected
test systems the TSC frequency is not refined against HPET, so it is
registered with the same frequency as the TSC-early clocksource.

As a consequence the update function which checks for a change of the
shift/mult pair of the clocksource fails to compute the conversion
limit, which is zero initialized. This check is there to avoid pointless
computations on every timekeeping update cycle (tick).

So the actual clockevent conversion function limits the delta expiry to
zero, which means the timer is always programmed to expire in the
past. This obviously results in a spectacular timer interrupt storm,
which goes unnoticed because the per CPU interrupts on x86 are not
exposed to the runaway detection mechanism and the NMI watchdog is not
yet functional. So the machine simply stops booting.

That did not show up in testing. All test machines refine the TSC frequency
so TSC has a differrent shift/mult pair than TSC-early and the conversion
limit is properly initialized.

Cure that by setting the conversion limit right at the point where the new
clocksource is installed.

Fixes: cd38bdb8e696 ("timekeeping: Provide infrastructure for coupled clockevents")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: John Stultz <jstultz@google.com>
Link: https://patch.msgid.link/87bjh4zies.ffs@tglx
Closes: https://lore.kernel.org/20260303012905.GA978396@ax162

The timekeeping_validate_timex() function validates the timex status
of an auxiliary system clock even when the status is not to be changed,
which causes unexpected errors for applications that make read-only
clock_adjtime() calls, or set some other timex fields, but without
clearing the status field.

Do the AUX-specific status validation only when the modes field contains
ADJ_STATUS, i.e. the application is actually trying to change the
status. This makes the AUX-specific clock_adjtime() behavior consistent
with CLOCK_REALTIME.

Fixes: 4eca49d0b621 ("timekeeping: Prepare do_adtimex() for auxiliary clocks")
Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260225085231.276751-1-mlichvar@redhat.com

Some architectures have clockevent devices which are coupled to the system
clocksource by implementing a less than or equal comparator which compares
the programmed absolute expiry time against the underlying time
counter. Well known examples are TSC/TSC deadline timer and the S390 TOD
clocksource/comparator.

While the concept is nice it has some downsides:

  1) The clockevents core code is strictly based on relative expiry times
     as that's the most common case for clockevent device hardware. That
     requires to convert the absolute expiry time provided by the caller
     (hrtimers, NOHZ code) to a relative expiry time by reading and
     substracting the current time.

     The clockevent::set_next_event() callback must then read the counter
     again to convert the relative expiry back into a absolute one.

  2) The conversion factors from nanoseconds to counter clock cycles are
     set up when the clockevent is registered. When NTP applies corrections
     then the clockevent conversion factors can deviate from the
     clocksource conversion substantially which either results in timers
     firing late or in the worst case early. The early expiry then needs to
     do a reprogam with a short delta.

     In most cases this is papered over by the fact that the read in the
     set_next_event() callback happens after the read which is used to
     calculate the delta. So the tendency is that timers expire mostly
     late.

All of this can be avoided by providing support for these devices in the
core code:

  1) The timekeeping core keeps track of the last update to the clocksource
     by storing the base nanoseconds and the corresponding clocksource
     counter value. That's used to keep the conversion math for reading the
     time within 64-bit in the common case.

     This information can be used to avoid both reads of the underlying
     clocksource in the clockevents reprogramming path:

     delta = expiry - base_ns;
     cycles = base_cycles + ((delta * clockevent::mult) >> clockevent::shift);

     The resulting cycles value can be directly used to program the
     comparator.

  2) As #1 does not longer provide the "compensation" through the second
     read the deviation of the clocksource and clockevent conversions
     caused by NTP become more prominent.

     This can be cured by letting the timekeeping core compute and store
     the reverse conversion factors when the clocksource cycles to
     nanoseconds factors are modified by NTP:

         CS::MULT      (1 << NS_TO_CYC_SHIFT)
     --------------- = ----------------------
     (1 << CS:SHIFT)       NS_TO_CYC_MULT

     Ergo: NS_TO_CYC_MULT = (1 << (CS::SHIFT + NS_TO_CYC_SHIFT)) / CS::MULT

     The NS_TO_CYC_SHIFT value is calculated when the clocksource is
     installed so that it aims for a one hour maximum sleep time.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260224163429.944763521@kernel.org

On some architectures clocksource::read() boils down to a single
instruction, so the indirect function call is just a massive overhead
especially with speculative execution mitigations in effect.

Allow architectures to enable conditional inlining of that read to avoid
that by:

   - providing a static branch to switch to the inlined variant

   - disabling the branch before clocksource changes

   - enabling the branch after a clocksource change, when the clocksource
     indicates in a feature flag that it is the one which provides the
     inlined variant

This is intentionally not a static call as that would only remove the
indirect call, but not the rest of the overhead.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260224163429.675151545@kernel.org

When __do_ajdtimex() was introduced to handle adjtimex for any
timekeeper, this reference to tk_core was not updated. When called on an
auxiliary timekeeper, the core timekeeper would be updated incorrectly.

This gets caught by the lock debugging diagnostics because the
timekeepers sequence lock gets written to without holding its
associated spinlock:

WARNING: include/linux/seqlock.h:226 at __do_adjtimex+0x394/0x3b0, CPU#2: test/125
aux_clock_adj (kernel/time/timekeeping.c:2979)
__do_sys_clock_adjtime (kernel/time/posix-timers.c:1161 kernel/time/posix-timers.c:1173)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)

Update the correct auxiliary timekeeper.

Fixes: 775f71ebedd3 ("timekeeping: Make do_adjtimex() reusable")
Fixes: ecf3e7030491 ("timekeeping: Provide adjtimex() for auxiliary clocks")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260120-timekeeper-auxclock-leapstate-v1-1-5b358c6b3cfd@linutronix.de

Pull SoC driver updates from Arnd Bergmann:
 "This is the first half of the driver changes:

   - A treewide interface change to the "syscore" operations for power
     management, as a preparation for future Tegra specific changes

   - Reset controller updates with added drivers for LAN969x, eic770 and
     RZ/G3S SoCs

   - Protection of system controller registers on Renesas and Google
     SoCs, to prevent trivially triggering a system crash from e.g.
     debugfs access

   - soc_device identification updates on Nvidia, Exynos and Mediatek

   - debugfs support in the ST STM32 firewall driver

   - Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI

   - Cleanups for memory controller support on Nvidia and Renesas"

* tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits)
  memory: tegra186-emc: Fix missing put_bpmp
  Documentation: reset: Remove reset_controller_add_lookup()
  reset: fix BIT macro reference
  reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe
  reset: th1520: Support reset controllers in more subsystems
  reset: th1520: Prepare for supporting multiple controllers
  dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys
  dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets
  reset: remove legacy reset lookup code
  clk: davinci: psc: drop unused reset lookup
  reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC
  reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY
  dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support
  reset: eswin: Add eic7700 reset driver
  dt-bindings: reset: eswin: Documentation for eic7700 SoC
  reset: sparx5: add LAN969x support
  dt-bindings: reset: microchip: Add LAN969x support
  soc: rockchip: grf: Add select correct PWM implementation on RK3368
  soc/tegra: pmc: Add USB wake events for Tegra234
  amba: tegra-ahb: Fix device leak on SMMU enable
  ...

If kobject_create_and_add() fails on the first iteration, then the error
code is set to -ENOMEM which is correct. But if it fails in subsequent
iterations then "ret" is zero, which means success, but it should be
-ENOMEM.

Set the error code to -ENOMEM correctly.

Fixes: 7b5ab04f035f ("timekeeping: Fix resource leak in tk_aux_sysfs_init() error paths")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Malaya Kumar Rout <mrout@redhat.com>
Link: https://patch.msgid.link/aSW1R8q5zoY_DgQE@stanley.mountain