Pull VDSO updates from Thomas Gleixner:
- Consolidate the VDSO datastore further and provide support for
mlock_all() and prefaulting.
- Provide 32-bit legacy time related functionality only if
CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists,
but architecture code still exposes the legacy functionality even
disabled.
Clean this up by adding the missing guards and validating at build
time that the VDSO is legacy free if disabled.
- Consolidate the VDSO related config options in core and drivers,
which removes some non-sensical dependencies and quite an amount of
#ifdeffery.
- Clean up the PAGE_SIZE definition maze
* tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
random: vDSO: Drop custom PAGE_SIZE definitions
LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
clocksource/drivers/timer-riscv: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
clocksource/drivers/arm_arch_timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
clocksource/drivers/mips-gic-timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
MIPS: csrc-r4k: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY
kbuild: Support generated asm-headers in subdirectories
vdso: Rename HAVE_GENERIC_VDSO to VDSO_DATASTORE
vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
vdso: Automatically select HAVE_GENERIC_VDSO if necessary
MIPS: vdso: Stop using CONFIG_HAVE_GENERIC_VDSO
vdso: Remove the dependency on HAVE_GENERIC_VDSO from ARCH_HAS_VDSO_ARCH_DATA
futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
vdso/gettimeofday: Verify COMPAT_32BIT_TIME interactions
sparc: vdso: Respect COMPAT_32BIT_TIME
MIPS: VDSO: Respect COMPAT_32BIT_TIME
powerpc/vdso: Respect COMPAT_32BIT_TIME
ARM: VDSO: Respect COMPAT_32BIT_TIME
arm64: vdso32: Respect COMPAT_32BIT_TIME
...
Pull timer and timekeeping core updates from Thomas Gleixner:
- Fix a subtly inconsistency in the timekeeping code, which fails to
account for the monotonicity adjustment in ntp_error.
For small changes of the clocksource multiplicator (+/-1) which are
typically used by the NTP PLL this is hard to observe. But for larger
adjustments, e.g. caused by a direct frequency setting through
adjtimex() the one-time uncompensated offset is significant.
Cure this by adjusting ntp_error with the resulting offset so that
the discrepancy is smoothed away over time
- Make tick length calculations correct in NTP.
The timekeeping core takes the quantisation of the clocksource into
account when calculating the tick length to compensate for the
deviation of the nominal NTP_INTERVAL_LENGTH.
While timekeeping gets this right, NTP is not aware of that, which
means it operates on the nominal value and not on the actual value
which is determined by the clock source frequency. The rounding of a
coarse clocksource like the ACPI PM timer results in a +127 PPM
deviation.
Cure this by exposing the deviation to the NTP code so that it can
operate on the same data as the timekeeping core. This is purely
kernel internal. User space still sees the nominal tick lenght via
adjtimex().
- The accuracy of the NTP adjustments is fairly approximate as the code
assumes that the invocations are precisely in NTP interval frequency
ticks and the final adjustment can over and under-run.
Cure this by adjusting ntp_error by the intended skew on each tick to
achieve the desired rate.
- Handle the two competing skews of time offset and time adjustment
correctly by calculating the conflict portion between the skews and
adjusting both accordingly.
- A set of updates and improvements for the selftests
- The usual small fixes and improvements all over the place
* tag 'timers-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
selftests: timers: nsleep-lat: Check all calls to clock_nanosleep() and clock_gettime()
selftests: timers: nsleep-lat: Reuse kselftest error numbers
selftests: timers: nsleep-lat: Explicitly list the tested clocks
selftests: timers: nsleep-lat: Use NSEC_PER_MSEC define for unreasonable latency
selftests: timers: nanosleep: Report each test separately
selftests: timers: nanosleep: Explicitly handle timer_delete() failure
selftests: timers: nanosleep: Move all single clock tests out of the loop in main()
selftests: timers: nanosleep: Reuse kselftest error numbers
selftests: timers: nanosleep: Explicitly list the tested clocks
selftests: timers: nanosleep: Drop output alignment
selftests: timers: Use clock_name() and constants from clock-helpers.h
selftests: Add clock-helpers.h
timer_list: Use ktime_t over nanoseconds
timer_list: Use standard 'long long' format placeholders
hrtimer: Add a lockdep assertion to hrtimer_update_base()
timekeeping: Use u32 for clock_was_set_seq
timekeeping: Rename clockid_aux_valid() to clockid_is_aux_clock()
hrtimer: Account nr_retries on recovered interrupt retries
timers/itimer: Zero-init old itimerval before copy to userspace
nohz: Replace dead select with choice default
...
Pull SMP core updates from Thomas Gleixner:
- Reduce the preemption disabled sections in smp_call_function*().
The various smp call functions keep preemption disabled accross the
full operation which includes the wait for completion. Especially the
latter can take some time when one of the target CPUs is not
immediately responding to the IPI, which can result in large latency
spikes.
To improve this provide a per task CPU mask to track the CPUs to wait
for. That makes the information required for the wait task local and
therefore allows to reenable preemption before the wait.
While this comes with moderate extra memory cost this reduces SMP
function call induced latency measured in a fleet for high priority
tasks from ~17ms to ~1.5ms (~90%).
- Reduce the overhead of the CSD debug code by replacing the heavy
memory barriers with smp_store_release()/acquire()
- Remove obsolute unused hotplug states
* tag 'smp-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
scftorture: Remove preempt_disable() in scftorture_invoke_one()
smp: Remove preempt_disable() from on_each_cpu_cond_mask()
smp: Remove preempt_disable() from smp_call_function()
smp: Enable preemption early in smp_call_function_many_cond()
smp: Alloc percpu csd data in smpcfd_prepare_cpu() only once
smp: Use task-local IPI cpumask in smp_call_function_many_cond()
smp: Refactor remote CPU selection in smp_call_function_any()
smp: Enable preemption early in smp_call_function_single()
smp: Disable preemption explicitly in __csd_lock_wait()
cpu/hotplug: Remove CPUHP_AP_ARM_CORESIGHT_CTI_STARTING
smp: Use release stores for csd_lock_record() state
Pull futex updates from Thomas Gleixner:
- Improvements to various futex self tests:
- Conversion to the selftest harness
- Provide and use thread creation and synchronization helpers to
reduce the dependency on delays, which tend to fail on loaded test
systems
- New tests for validating owner exit scenarios for robust and PI
futexes
- Runtime detect supported features and skip the tests if the kernel
has no support
- A few minor fixes
* tag 'locking-futex-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
selftests/futex: Give circular-list nodes static storage
selftests/futex: Use thread synchronization helpers instead of usleep()
selftests/futex: Provide thread creation and synchronization helpers
selftests/futex: Dynamically skip unsupported tests
selftests/futex: Add FUTEX_LOCK_PI owner-exiting coverage
selftests/futex: Migrate robust_list to harness
selftests/futex: Migrate futex_priv_hash to harness
selftests/futex: Migrate futex_numa_mpol to harness
selftests/futex: Migrate futex_requeue_pi_signal_restart to harness
selftests/futex: Migrate futex_requeue_pi_mismatched_ops to harness
selftests/futex: Migrate futex_requeue_pi to harness
selftests/futex: Migrate futex_requeue to harness
selftests/futex: Migrate futex_wait_uninitialized_heap to harness
selftests/futex: Migrate futex_wait_private_mapped_file to harness
selftests/futex: Migrate futex_wait to harness
selftests/futex: Correct validation logic in waitv
selftests/futex: Migrate functional tests to harness
selftests/futex: Remove static keyword from 'head'
futex: Remove unnecessary NULL check before kvfree()
selftests/rseq: Replace glibc-specific __GNUC_PREREQ with portable check
Pull generic interrupt subsystem updates from Thomas Gleixner:
- Remove pointless NULL checks of the kstats_irqs field. That's a
historical left over and not longer required.
- Add Radu Rendec as reviewer. Radu thankfully stepped up to help
reviewing the interrupt core and the related drivers code.
- The usual small improvements and fixes
* tag 'irq-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
MAINTAINERS: Add Radu Rendec as reviewer for the interrupt subsystem
genirq/msi: Move misplaced EXPORT_SYMBOL_GPL for msi_domain_free_irqs_all()
parisc: Remove unnecessary NULL check of the kstat_irqs field
genirq: Remove unnecessary NULL check of the kstat_irqs field
irqdomain: Remove unnedded NULL check in __irq_domain_[de]activate_irq()
genirq/manage: Use irqd_get_parent_data() helper in __irq_get_irqchip_state()
irqdomain: Plug leak in irq_domain_alloc_irqs_locked() error path
Pull generic entry code updates from Thomas Gleixner:
- Make syscall user dispatching configurable
Not all architectures can makes use of syscall user dispatching.
Allow them to disable the feature completely.
- Consolidate stack randomization for the generic entry code and the
architectures using it.
Stack randomization on syscall entry was sprinkled throughout the
architecture specific low level entry code and in some cases at the
wrong points, e.g. before establishing state, which violates the
non-instrumentable constraints of that code.
Clean this up by integrating stack randomization into the generic
entry code helpers so that it is invoked at the earliest possible
point right after establishing state and converting all generic entry
code using architecture over.
- Clean up the syscall number handling in the generic entry code. It
works correctly for architectures which have a separate return value
storage in pt_regs, but fails to distinguish the case where user
space handed in -1 as syscall number from the case where the entry
code rejects it by returning -1 to the callers. Aside of that the
return value functionality of those interfaces is not really
intuitive.
Fix this by separating the decision to reject a syscall (user
dispatch, ptrace, seccomp ...) from the potential modification of the
syscall number through these mechanisms.
This solves most of the problems for architectures which do not have
a separate return value storage in pt_regs except for the case where
a tracepoint has a BPF script or a probe attached which overwrite
both the syscall number and the return value. But that's a problem
which cannot be solved in the generic code, that only can be
addressed by separating the storage model in the affected
architectures.
* tag 'core-entry-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
entry, treewide: Make syscall_enter_from_user_mode[_work]() indicate syscall execution
entry: Make return type of syscall_trace_enter() bool
entry: Rework trace_syscall_enter()
entry: Rework syscall_audit_enter()
syscall_user_dispatch: Introduce ARCH_SUPPORTS_SYSCALL_USER_DISPATCH
entry: Fix seccomp bypass after ptrace with TSYNC
x86/entry: Simplify the syscall number logic
x86/entry: Get rid of the sys_ni_syscall() indirection
x86/entry: Make syscall functions static
ptrace, treewide: Rename ptrace_report_syscall_entry() to ptrace_report_syscall_permit_entry()
seccomp, treewide: Rename and convert __secure_computing() to return boolean
entry: Use syscall number instead of rereading it
entry: Remove syscall_enter_from_user_mode()
x86/syscall: Use [syscall_]enter_from_user_mode_randomize_stack()
s390/syscall: Use enter_from_user_mode_randomize_stack()
riscv/syscall: Use syscall_enter_from_user_mode_randomize_stack()
powerpc/syscall: Use syscall_enter_from_user_mode_randomize_stack()
loongarch/syscall: Use syscall_enter_from_user_mode_randomize_stack()
entry: Provide [syscall_]enter_from_user_mode_randomize_stack()
randomize_kstack: Provide add_random_kstack_offset_irqsoff()
...
Pull scheduler updates from Ingo Molnar:
"Load-balancing updates:
- 'flatten the pick': improve cgroup scheduling, which has always
been problematic and painful, which has caused various scheduling
misbehavior such as the mishandling of reniced tasks et al.
Add various cgroup weight distribution methods via cgroup_mode:
'up', 'max', 'concur' and 'tasks' - with the default being 'concur'
which is the most precise yet also most expensive version.
Finally, change cgroup scheduling to a single runqueue (Peter
Zijlstra)
- Series to improve the scheduling latency of short slice tasks
(Vincent Guittot)
- Series to fix cluster scheduling in the presence of asymmetric
capacity (Ricardo Neri)
- Prefer fully idle cores for NOHZ balancing (Andrea Righi)
- Don't trigger active load-balancing if src_rq->curr is not on_rq
(Xin Zhao)
PSI updates:
- Skip irqtime accounting when no new irq time has elapsed (Usama
Arif)
Scheduler debugging updates:
- Remove unused schedstats (Shrikanth Hegde)
- Defer freeing of cpumask memblock memory to initcall (Waiman Long)
Misc fixes and updates by Yu C Chen, K Prateek Nayak, Peter Zijlstra,
Vincent Guittot, Xin Zhao, Yury Norov, Zhan Xusheng"
* tag 'sched-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
sched/fair: Fix flat hierarchy
sched/isolation: Defer freeing of cpumask memblock memory to initcall
sched/topology: Restore SD_PREFER_SIBLING in domains with asymmetric capacity
sched/fair: Allow load balancing between CPUs of identical capacity
sched/fair: Skip misfit load accounting when the destination CPU cannot help
sched/fair: Check CPU capacity before comparing group types during load balance
sched/fair: Also gate overloaded status update for SD_ASYM_CPUCAPACITY
sched/fair: Do not skip CPUs of similar capacity with busy SMT siblings
sched/fair: Prefer fully idle cores for NOHZ balancing
stop_machine: Make stop_one_cpu_nowait() return void
sched/eevdf: Delayed dequeue task can't preempt
sched/fair: Fix stale comments referring to removed CFS concepts
sched/debug: Remove unused schedstats
sched/psi: skip irqtime accounting when no new irq time has elapsed
sched/fair: Reflow sched_balance_rq()
sched/fair: Simplify balance_interval reset logic in sched_balance_rq()
sched/fair: Don't trigger active lb if src_rq->curr is not on_rq
sched/eevdf: Speedup short slice task scheduling
sched/eevdf: Always update slice protection
sched/eevdf: Cancel slice protection if short slice task is eligible
...
Pull locking updates from Ingo Molnar:
"Futexes:
- Use runtime constants for futex_hash computation (K Prateek Nayak,
Peter Zijlstra)
- Optimise the size check get_futex_key() (Sebastian Andrzej Siewior)
- Avoid private hash use-after-free on final put (Felix Hoffmann)
- Tell kmemleak we're not leaking __futex_queues (Peter Zijlstra)
Rust integration updates:
- Implement refcounted interrupt disable and SpinLockIrq for Rust
(Boqun Feng, Heiko Carstens, Joel Fernandes, Lyude Paul)
- Rust sync: add helpers for mb, dma_mb and friends; add generic
memory barriers and use LKMM atomics instead of Rust atomics in the
revocable code (Gary Guo)
- Add abstraction and integrate synchronize_rcu() (Philipp Stanner)
Lock debugging:
- Add qspinlock contended_release tracepoint (Dmitry Ilvokhin, Peter
Zijlstra)
- Enable the printing of held locks of remote running tasks and print
task CPU (Ingo Molnar)
- percpu-rwsem: Annotate intentional data race in readers_active_check()
(Sun Shaojie)
Misc fixes and updates by Boqun Feng, Peter Zijlstra, Fangrui Song,
Naveen Kumar Chaudhary and Thomas Huth"
* tag 'locking-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
rust: sync: Introduce SpinLockIrq::lock_with() and friends
rust: sync: Add SpinLockIrq
rust: sync: Use super::* in spinlock.rs
rust: helper: Add spin_{un,}lock_irq_{enable,disable}() helpers
rust: Introduce interrupt module
s390/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
arm64: sched/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
preempt: Introduce HAS_SEPARATE_PREEMPT_RESCHED_BITS
sched: Avoid signed comparison of preempt_count() in __cant_migrate()
sched: Remove the unused preempt_offset parameter of __cant_sleep()
locking: Switch to _irq_{disable,enable}() variants in cleanup guards
irq: Add KUnit test for refcounted interrupt enable/disable
irq,spin_lock: Add counted interrupt disabling/enabling
openrisc: Include <linux/cpumask.h> in smp.h
preempt: Introduce __preempt_count_{sub,add}_return()
preempt: Introduce HARDIRQ_DISABLE_BITS
preempt: Track NMI nesting to separate per-CPU counter
futex: Tell kmemleak we're not leaking __futex_queues
x86/paravirt: Trace contended_release on unlock
tracing/lock: Use TRACE_EVENT_FN() for contended_release
...
Pull performance events updates from Ingo Molnar:
"uprobes updates:
- Fix a category of bugs with optimized uprobes that can clobber the
redzone area with call instruction storing return address on stack
where user code may keep temporary data without adjusting RSP.
Fix this by moving the optimized uprobes on top of 10-bytes NOP
instruction, so we can squeeze another instruction to escape the
redzone area before doing the call (Jiri Olsa, Andrii Nakryiko)
- Switch uretprobes_srcu to SRCU-fast-updown, to improve performance
(Puranjay Mohan)
Intel CPU PMU driver updates:
- Optimize ACR handling in match_prev_assignment() (Dapeng Mi)
- Fix various PMU driver bugs and data leaks (Dapeng Mi)
- Fix Intel PT stop/start with no update (Adrian Hunter)
Intel uncore PMU driver updates:
- Fix various uncore PMU setup robustness bugs (Zide Chen)
AMD uncore PMU driver updates:
- Add group validation (Sandipan Das)
.. and misc fixes and updates by Dapeng Mi, Randy Dunlap and Zide Chen"
* tag 'perf-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
perf/x86: Optimize ACR handling in match_prev_assignment()
perf/x86/intel: Fix intel_cap handling on hybrid PMUs
perf/x86: Remove stale fixed counter helper and fix hybrid PMU access
perf/x86/intel: Unwind cpuc state if PEBS buffer setup fails
perf/x86: Guard intel_pmu_cpu_dead() against invalid hybrid PMU casts
perf/x86: Free hybrid state on PMU init failure
perf/x86: Unregister PMI handler on PMU init failure
perf/x86/intel/pt: Fix stop/start with no update
perf/x86/intel/pt: Use bitwise access for PERF_HES_STOPPED
perf/x86/intel/pt: Factor out pt_config_enable()
uprobes: Switch uretprobes_srcu to SRCU-fast-updown
srcu: Add lock guard for srcu_fast_updown flavor
perf/x86/intel/pt: Drop kernel-doc for deleted struct members
perf/x86/amd/uncore: Add group validation
selftests/bpf: Add tests for forked/cloned optimized uprobes
selftests/bpf: Add tests for uprobe nop10 red zone clobbering
selftests/bpf: Add reattach tests for uprobe syscall
selftests/bpf: Change uprobe/usdt trigger bench code to use nop10
selftests/bpf: Change uprobe syscall tests to use nop10
selftests/bpf: Emit nop,nop10 instructions combo for x86_64 arch
...
Pull liveupdate updates from Mike Rapoport:
"Kexec Handover:
- Fix size calculation in kho_preserved_memory_reserve() for
preservations larger than 2 GiB
Live Update Orchestrator:
- move liveupdate selftest utilities into a library so that selftests
of subsystems participating in liveupdate, e.g. PCI and VFIO, can
use them and drop direct ioctl calls from the tests
- add end to end liveupdate test infrastructure that allows running
the tests across a kexec in QEMU
- remove redundant INIT_LIST_HEAD in luo_session_alloc()
- remember the error status of an FLB retrieve() and return it on
subsequent attempts rather than retrying retrieve() with an FLB in
an unexpected state
- reference count the outgoing FLB so that it cannot be freed while a
caller is using it, the same way it's done for the incoming FLB
- reject nonzero reserved field in LIVEUPDATE_SESSION_FINISH so that
it can be reused by a future extension"
* tag 'liveupdate-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux:
kho: fix size calculation in kho_preserved_memory_reserve()
selftests/liveupdate: Move luo_test_utils.* into a reusable library
selftests/liveupdate: Use luo_test_utils.c for liveupdate ioctl APIs
liveupdate: Remember FLB retrieve() status
liveupdate: Reference count outgoing FLB data
liveupdate: reject nonzero reserved value for SESSION_FINISH
liveupdate: Remove redundant INIT_LIST_HEAD in luo_session_alloc
selftests/liveupdate: add end to end test infrastructure and scripts
Pull kexec updates from Mike Rapoport:
- Deduplicate crash memory allocation and the exclusion of reserved
crash kernel regions from architecture specific code into a generic
crash_prepare_headers() and enable crashkernel CMA reservation on
arm64 and riscv reservation on arm64 and riscv.
- Skip purgatory checksum verification when the kexec segments cannot
be corrupted by DMA, which saves about 250ms on kexec.
- Replace __ASSEMBLY__ with the compiler provided __ASSEMBLER__ in
include/linux/kexec.h.
- Fix a keyring refcount imbalance in the kdump kernel's dm-crypt key
restore path, which over-dropped the user keyring reference when
more than one key was restored.
* tag 'kexec-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux:
crash_dump: release keyring reference at the correct time
kexec: Replace __ASSEMBLY__ with __ASSEMBLER__ in header file
kexec_file: skip checksum verification when safe
riscv: kexec_file: Add support for crashkernel CMA reservation
arm64: kexec_file: Add support for crashkernel CMA reservation
powerpc/kexec_file: Use crash_exclude_core_ranges() helper
LoongArch: kexec_file: Use crash_prepare_headers() helper to simplify code
riscv: kexec_file: Use crash_prepare_headers() helper to simplify code
x86/crash: Use crash_prepare_headers() helper to simplify code
arm64: kexec_file: Use crash_prepare_headers() helper to simplify code
crash: Add crash_prepare_headers() to exclude crash kernel memory
powerpc/crash: sort crash memory ranges before preparing elfcorehdr
riscv: kexec_file: Fix crashk_low_res not exclude bug
Pull power management updates from Rafael Wysocki:
"As has been the case for quite some time, this set of changes is
dominated by cpufreq updates including intel-pstate and amd-pstate
driver updates, minor fixes and cleanups of other assorted cpufreq
drivers, schedutil governor updates, fixes of the Rust bindings, new
hardware support (IPQ5210 in qcom-nvmem), and some updates of self
tests related to cpufreq.
The second largest group of changes are cpuidle updates consisting of
intel_idle driver updates and ACPI processor idle driver updates, both
mostly related to ACPI _LPI support.
There are also updates related to system sleep, mostly in the
hibernation core code, two operating performance points (OPP) updates,
one runtime PM framework update, one power capping update, and some
tools updates including the addition of ACPI CPPC support to cpupower.
Specifics:
- Minor fixes and cleanups in assorted cpufreq drivers (Dan
Carpenter, Guru Das Srinagesh, Haoxiang Li, Karl Mehltretter, Sasha
Finkelstein, and Pan Chuang)
- Fix cpufreq table creation and bios_limits() callback in the Rust
bindings (Priya Bala Govindasamy)
- Add IPQ5210 support to qcom-nvmem driver (Varadarajan Narayanan)
- Adjust the .adjust_perf() cpufreq driver callback to allow the
maximum performance value to be passed to drivers and update the
intel_pstate driver to use it (Rafael Wysocki)
- Set policy->cur to the actual requested frequency in the
intel_pstate driver when the performance policy is used (Rafael
Wysocki)
- Simplify HWP handling on Broadwell processors in intel_pstate
(Rafael Wysocki)
- Fix setting minimum P-state at init time in intel_pstate (Rafael
Wysocki)
- Consolidate frequency values computation in intel_pstate and clean
up code in that driver (Rafael Wysocki)
- Add missing kernel-doc descriptions for structure and union members
in the amd-pstate driver (David Vernet)
- Handle missing policy in dynamic EPP callbacks in the amd-pstate
driver (EDAMAMEX)
- Introduce EXPORT_SYMBOL_FOR_PSTATE_UT() to export amd-pstate driver
symbols to the amd-pstate-ut subdriver (K Prateek Nayak)
- Add dynamic EPP as an "energy_performance_preference" mode in
amd-pstate, remove the "amd_dynamic_epp" kernel command line option
and the "dynamic_epp" sysfs attribute, and update the dynamic_epp
documentation accordingly (K Prateek Nayak)
- Add unit tests for CPPC Performance Priority and the "dynamic" EPP
mode in the amd-pstate driver (K Prateek Nayak)
- Set min_limit_freq based on bios_min_perf in amd-pstate and remove
the defensive check for bios_min_perf from it (K Prateek Nayak)
- Fix EPP return type and handle errors in amd-pstate during
initialization, toggle auto_sel in active mode on shared memory
systems, and cache the firmware programmed EPP value (Marco
Scardovi)
- Skip tests in amd-pstate-ut if the amd-pstate driver is not in
active use (Qianheng Peng)
- Replace sprintf() with sysfs_emit() in sysfs show in the cpufreq
schedutil governor and fix a self-contradictory comment in
sugov_iowait_apply() (Zhongqiu Han)
- Fix the usage example for the sampling_rate tunable of the ondemand
cpufreq governor in admin-guide (wangxiaodong)
- Avoid using deep idle states during initialization in the
intel_idle driver to work around device handling issues (Rafael
Wysocki)
- Fix and refactor the ACPI processor driver code related to ACPI
_LPI support and add ACPI _LPI support to intel_idle based on that
ACPI processor driver update (Rafael Wysocki)
- Backup and restore governor for cpufreq sptests (Yiwei Lin)
- Remove unnecessary sudo from quick_shuffle() and remove unused
local variables from switch_show_governor() in cpufreq selftests
(Jinseok Kim)
- Rename the PM core module parameter prefix to "pm" and allow the PM
transition (DPM) watchdog to be disabled by default (Tzung-Bi Shih)
- Fix off-by-one in wakelocks number limit check in the system sleep
sysfs interface (Haowen Tu)
- Remove kernel-doc markings from helper descriptions in the core
hibernation code (Adi Nata)
- Use %pe to print error pointer values in the hibernation core
(Ronan Marchal)
- Fix memory leak in snapshot_write_next() error path (Malaya Kumar
Rout)
- Delay allocating and linking the next swap_map_page in the
hibernation image saving code until another image page actually
needs to be recorded (Haesung Kim)
- Fix cleanup ordering around scope-based pointers in OPP (Gregor
Herburger).
- Use clk_get_optional() for optional clocks in OPP (Praveen Talari).
- Stop setting runtime_error on runtime resume callback failures to
allow drivers to recover from resume issues (Praveen Talari)
- Handle PMU registration failure during probe in the intel_rapl_tpmi
driver (Sumeet Pawnikar)
- Avoid optional imports in intel_pstate_tracer unless they are
really needed (Yousef Alhouseen)
- Add generic CPPC performance display to the cpupower utility, build
and call CPPC information on non-AMD processors, make cpupower
print kernel and hardware frequency information, and add libm to
cpupower for generic CPPC view (Jeremy Linton)
- Remove conditional return with no effect from cpupower (Sang-Heon
Jeon)"
* tag 'pm-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
cpufreq: imx6q: fix out-of-bounds write when probed more than once
cpufreq: imx6q: fix devres accumulation across driver rebind
rust: cpufreq: Fix temporary write in Registration::bios_limit_callback
rust: cpufreq: Add CPUFREQ_TABLE_END as last table entry in TableBuilder::to_table
opp: Use clk_get_optional() to avoid leaving opp_table->clk as an error pointer
intel_idle: Avoid using deep idle states during initialization
cpupower: remove conditional return with no effect
cpufreq: intel_pstate: Adjust policy->cur in active mode to policy
cpufreq/amd-pstate: Document missing kernel-doc members
cpufreq/amd-pstate-ut: Add unit test for CPPC Performance Priority
cpufreq/amd-pstate-ut: Add unit test for "dynamic" EPP mode
cpufreq/amd-pstate: Reduce the scope of exported symbols
Documentation/amd-pstate: Update dynamic_epp documentation with new behavior
cpufreq/amd-pstate: Remove "amd_dynamic_epp" cmdline and "dynamic_epp" sysfs
cpufreq/amd-pstate: Add dynamic EPP as an "energy_performance_preference" mode
cpufreq/amd-pstate: Extract platform profile to EPP conversion into a helper
cpufreq/amd-pstate: Remove the defensive check for bios_min_perf
cpufreq/amd-pstate: Set min_limit_freq based on bios_min_perf
powercap: intel_rapl_tpmi: Handle PMU registration failure during probe
PM: sleep: Allow disabling DPM watchdog by default
...
Pull cachefiles ondemand removal from Christian Brauner:
"This sunsets cachefiles ondemand mode.
It was an effort to make fscache usable as a kernel cache for lazy
pulling. EROFS over fscache was its only in-tree user. fscache has
since become netfslib-oriented while EROFS never acts as a network
filesystem and EROFS over fscache has been removed.
So this cleans up the netfs, fscache and cachefiles side as well"
* tag 'vfs-7.3-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
cachefiles,netfs: sunset ondemand mode
Pull kthread vfs updates from Christian Brauner:
"This stops kernel threads from sharing filesystem state with
userspace. This work is about 3 cycles old and has been in -next
for about that time.
When the kernel boots init_task creates PID 1 and then kthreadd. From
that point every kthread and PID 1 share the same fs_struct. That is
why pivot_root() has to rewrite the fs_struct of all kthreads. The
rewriting exists so that kthreads can use init's filesystem state when
they want to. It also means userspace can move the ground out from
under the kernel.
PID 1 now gets a completely separate fs_struct. All kthreads are
anchored in a private SB_KERNMOUNT instance of nullfs that cannot be
mounted on and cannot be used to follow other mounts. Userspace init
can no longer affect kthread filesystem state and kthreads can no
longer affect userspace fs state without explicit opting in to that.
Path lookup from a kthread now fails by default. It makes it
deliberately hard to offload security sensitive operations into init's
filesystem state from a kthread.
Places that legitimately need to look something up there opt in
through the new scoped_with_init_fs() which temporarily overrides the
caller's fs_struct with init's. usermodehelpers remain the only kernel
tasks that genuinely share init's filesystem state, since they execute
random binaries in the root filesystem (excellent...).
The visible result is that /proc/2/root is a nullfs with an empty
mountinfo while /proc/1/root is the real root"
* tag 'vfs-7.3-rc1.kthread' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
initramfs_test: use test init/exit hooks to override init fs
fs: stop rewriting paths for PF_EXITING | PF_DUMPCORE
fs: stop rewriting kthread fs structs
fs: start all kthreads in nullfs
nullfs: make nullfs multi-instance
devtmpfs: create private mount namespace
fs: add umh argument to struct kernel_clone_args
fs: stop sharing fs_struct between init_task and pid 1
af_unix: use scoped_with_init_fs() for coredump socket lookup
initramfs: use scoped_with_init_fs() for rootfs unpacking
pnfs/blocklayout: use scoped_with_init_fs() for SCSI device lookup
ksmbd: use scoped_with_init_fs() for VFS path operations
ksmbd: use scoped_with_init_fs() for filesystem info path lookup
ksmbd: use scoped_with_init_fs() for share path resolution
fs: use scoped_with_init_fs() for kernel_read_file_from_path_initns()
coredump: use scoped_with_init_fs() for coredump path resolution
btrfs: use scoped_with_init_fs() for update_dev_time()
scsi: target: use scoped_with_init_fs() for APTPL metadata
scsi: target: use scoped_with_init_fs() for ALUA metadata
crypto: ccp: use scoped_with_init_fs() for SEV file access
...
Pull binfmt updates from Christian Brauner:
"This contains a bunch of work for binfmt_misc. It fixes a bunch of
old bugs, reworks the locking, and then extends the format registry
so a binary type can be matched programmatically and its interpreter
computed per exec instead of being a fixed string recorded at
registration time.
This allows nixos and other to e.g., implement relocatable binaries
meaning the interpreter/dynamic loader can be determined
programatically, say found relative to the binary. The mechanism is
flexible and can support other policies:
- Handler lookup is now an rcu walk. An exec that matches no
binfmt_misc entry should now never write to a shared cacheline
- remove the VERBOSE_STATUS and USE_DEBUG compile time toggles
- convert the entry file to a seq_file which simplifies things quite
a bit and kills a lot of custom logic
- make flags proper enums
- rename struct Node to binfmt_misc_entry
- allow entries to be removed with unlink(2)
- Add the ability to attach bpf programs to binfmt_misc entries so
it's possible to dynamically choose the execution environment such
as the loader or interpreter on a per binary basis.
A handler is an instance of a binfmt_misc_ops struct_ops with a
->match() and a ->load() program. match() decides from the entry
lookup walk whether the handler applies under the same
registration-order. It can read file content as needed not only the
prefetched 256 bytes in bprm->buf.
load() then selects the interpreter and stages it through the new
bpf_binprm_set_interp(), bpf_binprm_set_interp_arg() and
bpf_binprm_set_flags() kfuncs.
Handlers are published in a registry keyed by the registering
task's user namespace and activated through the existing text
interface with a new 'B' type carrying the handler name:
echo ':origin:B::::nix:' > /proc/sys/fs/binfmt_misc/register
The permission and namespacing model is unchanged. Activating a
handler requires the same write access to an instance as any other
registration. A container mounting its own instance escapes the
host's entries exactly as before. The computed interpreter is
opened with open_exec() under the caller's credentials and goes
through full LSM vetting as the next binprm level. A program can
only ever redirect the caller to something the caller could exec
anyway.
- Two dispatch modes are added. So far the chosen interpreter owns
the whole process identity (argv[0], /proc/pid/cmdline,
/proc/self/exe all name interpreter information). So relocatable
find the dynamic linker instead. Also a binary passed to execveat()
as an inaccessible O_CLOEXEC fd cannot run at all and gdb trips
because AT_ENTRY and AT_PHDR do not match the exe file. So PIE
symbols are unrelocated.
This adds transparent dispatch which allows the interpreter to load
the binary through AT_EXECFD and leaves the argument vector exactly
as the caller built it and labels mm->exe_file and comm with the
binary. It also raises the AT_FLAGS_TRANSPARENT_INTERP aux vector
bit. The interpreter keeps control of mapping the binary.
The second mode is loader substitution. This allows a binary to be
executed natively and only the interpreter to be changed.
- Last, interpreters can be bound at registration time. Each
interpreter is opened by its own write with the credentials the
entry file was opened with. The program picks one per exec with
bpf_binprm_select_interp().
Ucounts are used to properly account for pre-opened interpreters
via /proc/sys/user/max_binfmt_misc_interpreters"
* tag 'vfs-7.3-rc1.binfmt' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (63 commits)
binfmt_misc: document the pre-opened interpreter limit
selftests/exec: test the pre-opened interpreter limit
binfmt_misc: correctly account pre-opened interpreters
binfmt_misc: document interpreters bound by a 'B' entry
selftests/exec: test interpreters bound to a 'B' entry
binfmt_misc: let a 'B' entry bind its interpreters
binfmt_misc: carry pre-opened interpreters in struct binfmt_misc_interp
selftests/exec: share the bpf handler preconditions
binfmt_misc: document registering an entry disabled
selftests/exec: test registering an entry disabled
selftests/exec: let binfmt_flag_supported() return a bool
selftests/exec: check that a binfmt_misc instance cannot be pinned
binfmt_misc: let a register string create an entry disabled
binfmt_misc: document loader substitution
selftests/exec: test binfmt_misc loader substitution
binfmt_misc: let a bpf handler request loader substitution
binfmt_misc: add the 'L' loader substitution flag
binfmt_elf_fdpic: consume a stashed PT_INTERP substitute
binfmt_elf: consume a stashed PT_INTERP substitute
exec: carry a PT_INTERP substitute in struct linux_binprm
...
Pull misc ipc and core updates from Christian Brauner:
- reject mq_notify() with a zero signal number
- fix coding style in the exit path
* tag 'ipc-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
mqueue: reject mq_notify with signo 0
* tag 'kernel-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
kernel: exit: fix coding style missing spaces
Pull scheduler fix from Borislav Petkov:
- Make sure a delayed sched entity's runtime stats are updated at the
right time so that it receives the proper lag compensation
* tag 'sched_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Update time before requeueing delayed entities
Pull perf fixes from Borislav Petkov:
- Prevent the use of exited events as group leaders
- Avoid use-after-free of an event's group leader by promoting detached
sibling events to standalone entities and correct related accounting
and state transitions
* tag 'perf_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix group leader use-after-free after sibling detach
perf: Reject exited events as group leaders
Pull vfs fixes from Christian Brauner:
- Don't warn when a mount is completed from another user namespace.
fsopen() records the caller's user namespace in fc->user_ns and
hands back an ordinary file descriptor. The task that calls
fsconfig(FSCONFIG_CMD_CREATE) doesn't have to be the one that
created the context, and mount_capable() lets it through as long
as the caller has CAP_SYS_ADMIN over fc->user_ns, which anyone in
an ancestor namespace does. So fc->user_ns != current_user_ns()
is something an unprivileged user can arrange.
Both overlayfs and binfmt_misc WARN_ON() that. Overlayfs already
has the same check as a plain error return in ovl_parse_param().
Drop the WARN_ON() and just refuse. Add selftests for both cases.
- Reject pid allocations through dead ancestor pid namespaces.
Require PIDNS_ADDING in every namespace that will receive the pid
before publishing any of them. That preserves the invariant that
free_pid() never decrements pid_allocated in a namespace whose
child_reaper is no longer live. The existing ENOMEM behavior is
unchanged.
* tag 'vfs-7.2-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
pid: reject allocations through dead ancestor pid namespaces
selftests/filesystems: test completing a context from another user namespace
binfmt_misc: don't warn when the mount is completed from another user namespace
ovl: don't warn when the mount is completed from another user namespace
When a fair task is enqueued, we must update curr and more precisely
its vruntime before placing the enqueued task so avg vruntime will take
into account the last exec phase.
Example:
TA is an always running task in cgroup G0.
TB is a short running task (cyclictest) in cgroup G1.
The lag of TB always increases up the clamp limit because TB is placed
before TA(curr) is updated (since the last tick). When curr(TA) is
finally updated, its last exec phase provide positive lag to TB
Because TA and TB don't belong to the same group, enqueue_hierarchy() will not
update TA's entity when updating curr but only G0's entity at root level.
The same applies when dequeuing.
This is because update_curr() uses ->h_curr, rather than ->curr, and therefore,
while it is invoked on the root cfs_rq, which contains all the eevdf bits, it
does not do the right thing.
Fixes: 85570f10a4 ("sched/eevdf: Move to a single runqueue")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260812125039.1717249-1-vincent.guittot@linaro.org
In order to compute the right lag, it is required to update time to 'now'.
Without this, the delayed entity might appear younger than it really is and
receive less compensation for having waited.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
The following sequence may leads race between event_define_fields()
and update_event_fields():
CPU0 (loads module A) CPU1 (loads module B)
=============================== ===============================
load_module(A) load_module(B)
notifier_call_chain notifier_call_chain
trace_module_notify trace_module_notify
mutex_lock(&event_mutex) trace_event_update_all()
trace_module_add_events(A) down_write(&trace_event_sem)
__register_event(call_A)
__add_event_to_tracers(call_A)
event_define_fields(call_A)
for each f: list_for_each_entry(field,
list_add(&f->link, &class->fields, link)
&class->fields) field = class->fields->next;
Where access to the class->fields is not protected by the event_mutex in
trace_event_update_all().
This produces the following panic:
Unable to handle kernel access ... at virtual address 0000000000000018
pc : update_event_fields+0xf8/0x368
Call trace:
update_event_fields+0xf8/0x368
trace_event_update_all+0x7c/0x2b4
trace_module_notify+0x4c/0x1dc
notifier_call_chain+0x84/0x168
blocking_notifier_call_chain_robust+0x64/0xd4
load_module+0x10c8/0x123c
__arm64_sys_finit_module+0x230/0x31c
Fix by taking event_mutex in trace_event_update_all() before
trace_event_sem.
Cc: stable@vger.kernel.org
Fixes: b3bc8547d3 ("tracing: Have TRACE_DEFINE_ENUM affect trace event types as well")
Link: https://patch.msgid.link/2e5730d2-c631-da41-3a3a-ae35bb4895f3@allwinnertech.com
Signed-off-by: Michael Wu <michael@allwinnertech.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
A module-only event filter such as ":mod:foo" is cached with a NULL
event_mod->match when foo has not been loaded. If a later write tries to
remove a specific match from the same module, remove_cache_mod() passes
the NULL cached match to strcmp(), causing a NULL pointer dereference.
The issue can be reproduced from userspace:
echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event
echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event
The second write must be a concatenation (">>") to not include O_TRUNC as
that would cause ftrace_clear_events() to clear the cached modules lines.
The crash was reproduced on x86_64 QEMU while KUnit workers contended on
the event tracing path:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
RIP: 0010:strcmp+0x10/0x30
Call Trace:
__ftrace_set_clr_event_nolock+0x373/0x4a0
ftrace_set_clr_event+0xf0/0x180
ftrace_event_write+0xdf/0x110
vfs_write+0xf6/0x440
ksys_write+0x68/0xe0
do_syscall_64+0xf9/0x540
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Check event_mod->match before comparing it, consistent with the existing
NULL checks for the cached system and event fields. The mismatched removal
continues to return -EINVAL; a broad cached module filter is removed with
"!:mod:<module>".
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260811173902.1927376-2-sh_def@163.com
Fixes: b355247df1 ("tracing: Cache \":mod:\" events for modules not loaded yet")
Reported-by: syzbot+4d3143c8e28f6266c636@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/lkml/6a7a6b7f.9c11d2ce.289b96.00f8.GAE@google.com/
Signed-off-by: Hui Su <sh_def@163.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When testing a linux-next kernel with commit 59bd1d914b ("memblock:
warn when freeing reserved memory before memory map is initialized"),
the following warning was hit when there was a "nohz_full" kernel boot
parameter.
Cannot free reserved memory because of deferred initialization of the memory map
WARNING: mm/memblock.c:904 at __free_reserved_area+0xde/0xf0, CPU#0: swapper/0/0
:
Call Trace:
<TASK>
memblock_phys_free+0xcb/0x100
housekeeping_init+0x14c/0x170
start_kernel+0x207/0x450
x86_64_start_reservations+0x24/0x30
x86_64_start_kernel+0xda/0xe0
common_startup_64+0x13e/0x141
</TASK>
IOW, we shouldn't free memblock allocated memory so early
in the boot process when memory map isn't fully initialized in
deferred_init_memmap().
Fix it by saving the housekeeping cpumask memblock memory to be
freed into a llist free list in housekeeping_init() and add a new
housekeeping_late_init() helper to defer the actual freeing of memblock
memory to when initcall's are being processed. The cpumask memblock
memory is treated as a llist_node with the size of a "long" type which
is also smallest cpumask size that can be allocated.
The non-atomic version of the llist APIs are used as there is no
contention.
This commit depends on the presence of commit 7c2eee9c13 ("memblock:
don't touch memblock arrays when memblock_free() is called late")
to prevent a KASAN UAF bug report [1].
[1] https://lore.kernel.org/lkml/20260505051821.1107133-1-longman@redhat.com/
Fixes: 27c3a5967f ("sched/isolation: Convert housekeeping cpumasks to rcu pointers")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Link: https://patch.msgid.link/20260701195810.477326-1-longman@redhat.com
alloc_pid() checks PIDNS_ADDING only on the leaf pid namespace before
making a new struct pid visible in every ancestor namespace. That is
insufficient when an unborn descendant pid namespace outlives an
ancestor whose init task has already exited. The descendant can still be
initialized later through setns(), and the new pid is then published
into the dead ancestor as well.
Keep the existing ENOMEM behavior, but require PIDNS_ADDING to be set in
every namespace that will receive the new pid before publishing any of
them. This preserves the invariant that free_pid() never decrements
pid_allocated in a namespace whose child_reaper is no longer live.
Fixes: a3bdc23ba8 ("pid_namespace: allow opening pid_for_children before init was created")
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Re-arranging hrtimer_interrupt() switched the retry path to a local
counter and dropped the update of cpu_base->nr_retries, leaving the
field exported via /proc/timer_list stuck at zero.
Increment nr_retries only when another pass through the expiry loop
is started; the third attempt that falls through to hang handling is
still accounted by nr_hangs alone.
Fixes: 2889243848 ("hrtimer: Re-arrange hrtimer_interrupt()")
Signed-off-by: Liang Hao <haohlliang@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260731150408.19554-1-haohlliang@gmail.com
On native sparc64, struct __kernel_old_timeval contains a four-byte hole
after tv_usec because tv_sec is 64-bit while __kernel_suseconds_t is 32-bit.
put_itimerval() fills only the named fields in a stack-allocated
__kernel_old_itimerval and copies the entire object to userspace, so
getitimer() can expose the two padding holes.
Zero-initialize the aggregate before assigning the fields so implicit
padding is deterministic before it crosses the user/kernel boundary.
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Assisted-by: Codex:gpt-5
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260809190428.1523014-1-Jeremy.Jean@oss.cyber.gouv.fr
'select' does not work on config options in a 'choice', so currently the
'select VIRT_CPU_ACCOUNTING_GEN' for NO_HZ_FULL is dead, with the choice
option VIRT_CPU_ACCOUNTING_GEN only being enabled when NO_HZ_FULL=y because
the other choice members depend on NO_HZ_FULL=n.
Remove the dead select, and encode this relationship as a default of the
choice, instead.
This dead select was found by kconfirm, a static analysis tool for Kconfig.
Signed-off-by: Julian Braha <julianbraha@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20260801160140.2391000-1-julianbraha@gmail.com
If the auxiliary clock is disabled during tk_get_aux_ts64() but is enabled
before tks->clock_valid is checked, then uninitialized stackdata will be
used in the calculations and indirectly leaked to userspace.
The same race window also exists after this change and also for the core
timekeeper. But in these cases the only effect would be incorrect
adjustments and this is userspace's responsibility to avoid this.
Fixes: 4eca49d0b6 ("timekeeping: Prepare do_adtimex() for auxiliary clocks")
Signed-off-by: Thomas Weißschuh (Schneider Electric) <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260731-timekeeping-aux-adjtimex-return-v1-1-b7fea4692886@linutronix.de
The timekeeper update path uses a bulk memcpy() to synchronize the
timekeeper structure, which is not guaranteed to be atomic. This allows for
torn reads in ktime_get_real_seconds() on 64-bit systems, where the
sequence counter protection is bypassed for performance.
To prevent reading a torn 64-bit xtime_sec value, enforce atomic-like
access by using WRITE_ONCE() for the critical field before the bulk
memcpy() in timekeeping_update_from_shadow(). Correspondingly, use
READ_ONCE() in ktime_get_real_seconds() to ensure a fresh, consistent load
from memory.
[ tglx: Format changelog and add comment ]
Reported-by: syzbot+72789cd1697965e714ca@syzkaller.appspotmail.com
Signed-off-by: Dennis Moshegov <dennis@xzync.uk>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260724154405.70-1-dennis@xzync.uk
Closes: https://syzkaller.appspot.com/bug?extid=72789cd1697965e714ca
With the changes that enable preempt count to track IRQ disabling
nesting, we don't have enough bits in 32-bit preempt count
implementation, as a result we move NMI nesting bits out of the 32-bit
preempt count. However on the architectures that can support 64-bit
preempt count implementation, we can keep the NMI nesting bits in the
32-bit preempt count and avoid maintaining NMI nesting bits outside of
the same cache line.
Therefore HAS_SEPARATE_PREEMPT_RESCHED_BITS is introduced to allow
architectures to select this. Note that under this Kconfig, preempt
count is maintained in a 64-bit word however preempt_count() still
remains as an int because all the effective bits still fit in
(previously we mask out NEED_RESCHED bit in preempt_count()). This
should make no functional changes for existing preempt_count() users.
Enable this for x86_64 along with the introduction of the Kconfig.
[boqun: Undo the __preempt_count_{add,sub}() optimization in 32-bit
preempt count since it may introduce {over,under}flow]
Originally-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804161447.84806-11-boqun@kernel.org
Currently preempt_count() is always a non-negative int on all archs
(PREEMPT_NEED_RESCHED archs will mask out the MSB when returning
preempt_count()), hence the checking in __cant_migrate() is in fact just
checking whether preempt_count() is 0 or not. In a future change, we are
going to use all the 32 bits of preempt_count(), which would make
negative int values possible from preempt_count(). Therefore convert the
"> 0" comparison into a zero check to prepare for the future change.
No functional changes are intended.
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804161447.84806-10-boqun@kernel.org
The semantics of various IRQ disabling guards match what
*_irq_{disable,enable}() provide, i.e. the interrupt disabling is
properly nested, therefore it's OK to switch to use
*_irq_{disable,enable}() primitives.
[boqun: Adjust the user-side changes in do_sched_cfs_*_timer() provided
by Peter and Lyude]
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804161447.84806-8-boqun@kernel.org
While making changes to the refcounted interrupt patch series, at some
point on my local branch I broke something and ended up writing some kunit
tests for testing refcounted interrupts as a result. So, let's include
these tests now that we have refcounted interrupts.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804161447.84806-7-boqun@kernel.org
Currently the nested interrupt disabling and enabling is represented by
_irqsave() and _irqrestore() APIs, which are relatively unsafe, for
example:
<interrupts are enabled as beginning>
spin_lock_irqsave(l1, flag1);
spin_lock_irqsave(l2, flag2);
spin_unlock_irqrestore(l1, flags1);
<l2 is still held but interrupts are enabled>
// accesses to interrupt-disable protected data will cause races
This is even easier to trigger with guard facilities:
unsigned long flag2;
scoped_guard(spin_lock_irqsave, l1) {
spin_lock_irqsave(l2, flag2);
}
// l2 locked but interrupts are enabled.
spin_unlock_irqrestore(l2, flag2);
(Hand-to-hand locking critical sections are not uncommon for a
fine-grained lock design)
And because of this unsafety, Rust cannot easily wrap the
interrupt-disabling locks in a safe API, which complicates the design.
To resolve this, introduce a new set of interrupt disabling APIs:
* local_interrupt_disable();
* local_interrupt_enable();
They work like local_irq_save() and local_irq_restore() except that 1)
the outermost local_interrupt_disable() call saves the interrupt state
into a per-CPU variable, so that the outermost local_interrupt_enable()
can restore the state, and 2) a per-CPU counter is added to record the
nest level of these calls, so that interrupts are not accidentally
enabled inside the outermost critical section.
Also add the corresponding spin_lock primitives: spin_lock_irq_disable()
and spin_unlock_irq_enable(), as a result, code as follows:
spin_lock_irq_disable(l1);
spin_lock_irq_disable(l2);
spin_unlock_irq_enable(l1);
// Interrupts are still disabled.
spin_unlock_irq_enable(l2);
doesn't have the issue that interrupts are accidentally enabled.
This also makes the wrapper of interrupt-disabling locks on Rust easier
to design.
[boqun: Apply Peter's feedback and fix spell errors reported by Ingo]
[boqun: Address the duplicate spin_acquire() spotted by sashiko]
Co-developed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804182657.87716-1-boqun@kernel.org
Pull tracing fixes from Steven Rostedt:
- Fix use-after-free in eventfs_remove_rec()
The freeing of the eventfs_inode children used list_for_each_entry()
where the child is freed via srcu, but there's still a chance that it
gets freed. It should be using list_for_each_entry_safe().
- Fix eventfs_inode SRCU use of list in freeing
The iterator uses an SRCU protected list walk on the eventfs inodes.
The eventfs inode uses its "list" field in a union with the RCU list
head. When the inode gets added to the SRCU list it immediately
corrupts the list pointer and can cause an issue with the iterator.
Move the RCU list head to be shared with the children list head which
allows the iterator to check the parent inode if is freed before
referencing the child. Have the iterator check the parent "is_freed"
field and break out if it is set. Also add memory barriers to make
sure the ordering is correct.
- Fix various RCU synchronization issues with direct_functions
Updates to direct_functions have some missing RCU protection and
synchronization. Restructure the code a bit to make sure updates to
the direct_functions are protected.
- Remove an unneeded comma from a scope_guard()
There's a spurious comma in a scope_guard(). Remove it.
- Fix race in per CPU buffer swap in the ring buffer
When a per CPU buffer swap happens, it must make sure that it doesn't
occur while a writer is active. Instead it returns an -EBUSY. But
there's a small race window when a writer moves from one sub-buffer
to the next that it resets the "committing" counter. If a swap
happens at that moment, the buffer used for the commit of an event
will not match the buffer the event is actually on. Instead of using
the "committing" counter, use the recursive detection counter that
does not get reset when the writer crosses sub-buffers.
- Fix off-by-one in ftrace_free_mem()
The function ftrace_free_mem() gets an "end_ptr" as a parameter that
is exclusive to the rang to be freed. But its value is used to search
for the records that expects an inclusive value. Subtract one from
the parameter to convert it to an inclusive range.
- Disable resizing of the ring buffer for persistent buffers
Resizing the persistent buffer has undefined behavior. Prevent it
from being resized.
- Disable changing ring buffer subbuf order when resizing is disabled
The ring buffer subbuffer order can not be changed during resizing.
Use that instead of just checking if the buffer is mapped as mapped
buffers also have resizing disabled.
- Initialize subbuf_order of reader pages when they are created
In rb_allocate_cpu_buffer() the bpage->order is not updated to the
current subbuf_order leaving it as zero. This value is used when the
page is freed.
- Fix test_ringbuffer() to test for ERR_PTR before calling
kthread_stop()
The rb_threads[] array is assigned the output of kthread_run_on_cpu()
which could return an ERR_PTR. At the end of the test, all threads in
the array are cleaned up by kthread_stop() passing in the value in
the array if it isn't zero. But if the array contains an ERR_PTR,
kthread_stop() will not be able to handle it properly.
* tag 'trace-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Fix crash passing ERR_PTR to kthread_stop()
ring-buffer: Initialise reader page order in rb_allocate_cpu_buffer()
ring-buffer: Prevent subbuf order change when resizing is disabled
ring-buffer: Prevent resizing of persistent ring buffer
ftrace: Fix off-by-one fentry site disable in ftrace_free_mem()
ring-buffer: Use current_context for safe per-CPU buffer swap
ftrace: Drop extra comma in trace_buffered_event_enable
ftrace: Protect direct_functions in update_ftrace_direct_mod
ftrace: Protect direct_functions in update_ftrace_direct_del
ftrace: Protect direct_functions in ftrace_find_rec_direct
eventfs: Use children field for rcu head and add memory barriers
eventfs: Fix use-after-free in eventfs_remove_rec()
In test_ringbuffer()'s out_free cleanup loop, the check
`!rb_threads[cpu]` only catches NULL entries and misses entries that
hold an ERR_PTR.
rb_threads[] is static, so unassigned slots are NULL. But when
kthread_run_on_cpu() fails for a cpu, it stores ERR_PTR(-ENOMEM) (or
-EINTR) in rb_threads[cpu] before the creation loop jumps to out_free.
That entry is non-NULL, so the old `!ptr` check does not break, and the
cleanup proceeds to call kthread_stop() on the ERR_PTR. kthread_stop()
then dereferences the bogus pointer, crashing the kernel during the
late_initcall self-test.
crash logs:
BUG: kernel NULL pointer dereference, address: 000000000000001c
Oops: 0002 [#1] SMP NOPTI
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 7.2.0-rc6-dirty #7 PREEMPT(lazy)
RIP: 0010:kthread_stop+0x2e/0x220
RBX: fffffffffffffff4
CR2: 000000000000001c
Call Trace:
<TASK>
test_ringbuffer+0x1ec/0x650
do_one_initcall+0x6c/0x2c0
kernel_init_freeable+0x21d/0x420
kernel_init+0x15/0x1c0
ret_from_fork+0x21b/0x320
</TASK>
Kernel panic - not syncing: Fatal exception
Cc: stable@vger.kernel.org
Fixes: 64ed3a049e ("ring-buffer: make use of the helper function kthread_run_on_cpu()")
Link: https://patch.msgid.link/20260807154145.2846521-2-sh_def@163.com
Signed-off-by: Hui Su <sh_def@163.com>
Reviewed-by: Vincent Donnefort <vdonnefort@google.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When a module's init text is freed, do_init_module() calls
ftrace_free_mem() with a half-open [start, end) range. However the
ftrace_cmp_recs() comparator treats the upper bound as inclusive, as all
its other users do, passing 'ip + size - 1'. So ftrace_free_mem() can
delete a record sitting exactly at 'end', which is outside the freed
range.
For a kernel without CFI or IBT, the first record of a function is at
the function start, which for the first function in a module is also the
base of its text allocation. As the module allocator packs its regions,
that address is often the 'end' passed by a neighboring module's
do_init_module(), causing the first function's ftrace location to get
disabled, preventing an attempt to livepatch it:
livepatch: failed to find location for function 'pcspkr_probe'
Convert the exclusive end to the inclusive 'end - 1' the comparator
expects, and return early for an empty range to avoid the subtraction
from underflowing when the init text size is zero.
Cc: stable@vger.kernel.org
Fixes: 42c269c88d ("ftrace: Allow for function tracing to record init functions on boot up")
Link: https://patch.msgid.link/1b5ccfa8095bdb1277f84af1c2c2e2205aca03ae.1785992188.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
