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2026-08-19Merge tag 'tracefs-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-traceLinus Torvalds1-6/+7
Pull tracefs updates from Steven Rostedt: - Define event fields before directory creation Move the event_define_fields() call in event_create_dir() before the eventfs directory creation. Previously, a failure after directory creation wouldn't clean up eventfs_inode because the error path didn't call eventfs_remove_dir(). This eliminates the need to clean up the eventfs directories if event_define_fields() fails. - Add warning for out of bounds pos in __eventfs_iterate() Sashiko complains about the ctx->pos causing issues if it is less than 2 or greater than MAX_INT in __eventfs_iterate(). The thing is, the logic prevents that from happening. But to make Sashiko happy, add a WARN_ON() and exit safely if the function ever does get input that is out of the range the function expects. * tag 'tracefs-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: eventfs: Add warning for out of bounds pos in __eventfs_iterate() eventfs: Define event fields before directory creation
2026-08-19Merge tag 'trace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-traceLinus Torvalds13-75/+241
Pull tracing updates from Steven Rostedt: - Expose btf_ids to trace events In order to allow BPF programs to attach to system call trace events (which are actually pseudo trace events built on top of raw_syscall events), expose the BTF ID of the events. This will allow BPF programs better precision in attaching to events. - Use "u64" to assign to hist_field->type Instead of using kstrdup("u64", GFP_KERNEL) to assign the hist_field->type, just point it to "u64" instead. The hist_field->type is freed via kfree_const(). - Replace kmalloc()/strcpy() with kstrdup() for trace_printk Instead of having two calls to copy the module format string, just use kstrdup(). - Use __free() in trace event histograms and triggres where possible - Use seq_buf in trace event code instead of strcat() Instead of calculating the size of the buffer to use and filling it with strcat(), use the seq_buf infrastructure that takes care of making sure not to overflow the string size. - Reject invalid preemptirq_delay_test CPU affinity The preempt_delay_test module can take an invalid CPU affinity mask and create confusing output. Simply have the module reject invalid affinity masks. - Prevent division by zero in ftrace_ops sample module code If the ftrace_ops sample module code receives the module parameter nr_function_calls set to zero, it can cause a division by zero error. - Warn when an event dereferences a parameter in TP_printk() On boot up and module load, the trace event TP_printk() is scanned for possible bugs. As the TP_printk() code is executed when the user reads the "trace" file and processes the data written when the trace_event executed, the data it reads can be literally days old. The scan currently checks for dereferencing printk formats like "%pI6". But it does not check if the parameters themselves have a dereference like: TP_printk("offset %08x: value %08x", (u32)(__entry->addr - __entry->edma->membase), __entry->value) __entry represents the pointer to the event on the ring buffer. The __entry->edma->membase is dereferencing a pointer on the ring buffer to find membase, but the __entry->edma may no longer be a valid pointer. Warn on this case too. - Replace some strcpy() with strscpy() - Clean up mmiotrace events to use assign_type() macro The assign_type() macro makes sure the event type is indeed the type that is being parsed. The mmiotrace trace was written before that macro was created so it just simply typecasted the pointer. Replace the typecasting with the macro. - Have the ENUM processing to numbers only process what is added The code that converts ENUMs to their numbers in the trace events scanned all events to do the processing. This was true when a module was loaded too. That is, instead of processing just the events for the module, it processed *all* events. Even the builtin ones that were processed at boot up. Add a check for the event->module matching mod if it is a module before processing it. * tag 'trace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (21 commits) tracing: Have trace_event_update_all() only handle module that is loading tracing: Cleanup event_enable_trigger_parse() by using __free() tracing: Report every TP_printk double dereference tracing/mmiotrace: Use trace_assign_type() in mmio_print_mark() tracing: Make per-template BTF id lists file-local tracing: Use seq_buf for string concatenation tracing: Use strscpy() instead of strcpy() in trace_sched_switch tracing: Warn when an event dereferences a pointer in TP_printk() samples/ftrace: Prevent division by zero when nr_function_calls is zero tracing: Reject invalid preemptirq_delay_test CPU affinity fgraph: Use trace_seq_putc() in print_graph_return() tracing/user_events: Replace a seq_printf() call by seq_puts() in user_seq_show() tracing/user_events: Use seq_putc() in two functions tracing: Bound histogram expression strings with seq_buf tracing: Return ERR_PTR() from expr_str() tracing: Use __free() for expr_str() buffer kernel/trace/trace_printk: Use kstrdup() instead of kmalloc() and strcpy() tracing: Point constant hist field type to string literal selftests/bpf: Add test for tracepoint btf_ids tracefs file tracing: Expose tracepoint BTF ids via tracefs ...
2026-08-19Merge tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-traceLinus Torvalds1-37/+6
Pull ftrace updates from Steven Rostedt: - Deprecrate ftrace_enabled in disabling ftrace The file /proc/sys/kernel/ftrace_enabled was created when ftrace was first introduced back in 2008. It was to be a "kill switch" if something was to go wrong. It was also used as a way to turn off function tracing for the latency tracers that would have it on by default. But in 2013 (Linux 3.10) the option "function-trace" was introduced to disable function tracing for the latency tracers as the "ftrace_enabled" file was considered too big of a hammer and caused too many side effects. When live kernel patching came along, disabling ftrace via the ftrace_enabled file would put the system into an unstable state if a live kernel patch was installed. This created the need to mark some function hooks as "PERMANENT". Now there's a need for BPF usage marked as PERMANENT for the same reasons. The file "ftrace_enabled" usage is no longer viable. It doesn't do what it says it does and there is no reason to use it. Make writing '0' to it a nop and print a message saying its usage is deprecated. The return value of writing '0' is -EOPNOTSUPP so that user space will error on that write (hopefully to inform any developer that it no longer works). Eventually the file should be removed completely, but for now just making it not do anything is the path forward to that. - Update the livepatch tests to handle ftrace_enabled being disabled Because in the past, livepatch was broken by ftrace_enabled being turned off, there's a test case that checks to make sure it still doesn't break. But having the write of '0' return an error caused that test to break. Updated the test to handle the new change. * tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: selftests/livepatch: update test-ftrace.sh for deprecated ftrace_enabled ftrace: deprecate disabling via ftrace_enabled sysctl
2026-08-19Merge tag 'trace-rv-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-traceLinus Torvalds35-181/+1212
Pull Real-time Verifier updates from Steven Rostedt: - Switch LTL and DOT parsers to Lark in code generation tool The rvgen code generation tool originally parsed DOT files and LTL specifications using custom string parsing and Ply, which is no longer maintained. The DOT parser was fragile and prone to failure on minor format variations. Both LTL and DOT parsers have been rewritten to use the Lark parsing library. - Simplify Hybrid Automata clock variables The clock variables in hybrid automata monitors now use a single representation of the elapsed time since the clock was reset, rather than converting between invariant and guard representations. This allows simpler code generation for the newly refactored parser. - Generate cleanup hook for per-obj monitor The code generation scripts now adds a cleanup function to per-obj monitors for the user to wire to the appropriate event (e.g. sched_process_exit for tasks). - Reduce read_lock scope during per-task cleanup Take the tasklist_lock only when necessary, that is when iterating over for_each_process_thread(). - Simplify task monitor slot management Only rely on the slot array for per-task slot management to avoid inconsistency with the unused counter. - Improve rvgen code robustness and templates Use pathlib in rvgen and improve kernel path discovery. Also improve consistency across templates when generating code (e.g. author placeholder and monitor struct name). - Update rtapp sleep monitor Simplify the sleep monitor by excluding kernel threads and updating the nanosleep check to focus only on CLOCK_REALTIME. Also switch to use the sched_exit tracepoint to run in the context of the offending (wakee) task. - Add wakeup monitor Add the new rtapp/wakeup monitor to detect when lower-priority tasks wake up higher-priority ones, complementing the existing sleep monitor by running in the waker context and capturing its stack trace. - Fix tools/rv exit status on failure Ensure the rv tool returns a failure exit code when a monitor fails to start because it was already running. - Add automated selftests for tools/rv and rvgen Introduced automated bash selftests to validate rv monitor listing and execution under different configurations. Added tests for the rvgen code generator, validating generated files against expected output (golden). Tests are reachable via make check. - Add KUnit test coverage for verification monitors Added comprehensive KUnit tests to validate the functionality of deterministic, hybrid, and LTL monitors by emulating event sequences and timing in a mock environment without affecting the running kernel while expecting mock reactions to fire. Ensure real RV monitors cannot run during KUnit tests to avoid state corruption. - Mock current in rv monitors Mock the call to current in rv monitors when the KUnit tests are built to allow them to run the test on dummy tasks. No overhead is expected when KUnit tests aren't running. - Introduce rvgen kunit subcommand Added a new 'kunit' subcommand to rvgen to automatically patch an already generated monitor with KUnit integration templates by parsing its event handlers and creating the required mock structures and initializations. - Refine kernel verification selftests Added new selftests for the deadline and stall monitors and rearranged the existing wwnr_printk test to resolve flakiness. Additionally, fixed an issue in the selftests framework where negative assertion failures were not correctly propagated due to shell rules. - Fix 32-bit build of nomiss KUnit test A previous commit introduced a division between an u64 and a constant value and that doesn't build on 32-bit systems. Use div_u64() instead. - Document changes in sleep monitor The sleep monitor introduced some changes in the past like allowing epoll_wait() as a valid sleep and a task going to runnable before scheduling as a valid wakeup. Document both. * tag 'trace-rv-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (40 commits) Documentation/rv: Explain epoll and aborted sleeps rv: Fix 32-bit build of nomiss KUnit test selftests/verification: Add selftests for deadline and stall monitors selftests/verification: Rearrange the wwnr_printk test selftests/verification: Fix wrong errexit assumption rv: Add KUnit tests for some LTL monitors rv: Add KUnit mock for current rv: Add KUnit tests for some DA/HA monitors rv: Export task monitor slot and react symbols verification/rvgen: Add selftests for rvgen kunit verification/rvgen: Add the rvgen kunit subcommand verification/rvgen: Add selftests verification/rvgen: Add golden and spec folders for tests tools/rv: Add selftests verification/rvgen: Improve consistency in template files verification/rvgen: Use pathlib instead of os.path verification/rvgen: Improve rv_dir discovery in RVGenerator tools/rv: Fix exit status when monitor execution fails rv: Use generic rv_this for the rv_monitor variable in LTL rv/rtapp: Add wakeup monitor ...
2026-08-19Merge branch 'for-7.3-console-registration-cleanup' into for-linusPetr Mladek1-11/+8
2026-08-18Merge tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds3-9/+26
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 ...
2026-08-18Merge tag 'timers-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds17-173/+545
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 ...
2026-08-18Merge tag 'smp-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-78/+170
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
2026-08-18Merge tag 'locking-futex-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+1
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
2026-08-18Merge tag 'irq-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-16/+11
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
2026-08-18Merge tag 'core-entry-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds4-34/+64
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() ...
2026-08-18Merge tag 'sched-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds12-633/+934
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 ...
2026-08-18Merge tag 'locking-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds13-45/+308
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 ...
2026-08-18Merge tag 'perf-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds3-31/+50
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 ...
2026-08-18Merge tag 'liveupdate-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linuxLinus Torvalds3-9/+20
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
2026-08-18Merge tag 'kexec-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linuxLinus Torvalds3-8/+123
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
2026-08-18Merge tag 'pm-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds5-39/+62
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 ...
2026-08-18timer: Keep debugobjects state consistent in migrate_timer_list()Thomas Gleixner1-0/+1
When timers are migrated away from an offline CPU the debugobjects state gets corrupted. The timer is accounted as inactive on deletion, but the enqueue on the alive CPU lacks the activation call. That used to work, but got broken when the trace point and the debug objects call got separated. That change missed to fixup migrate_timer_list(). Add the missing debug_timer_activate() invocation to fix it. Fixes: dc1e7dc5ac62 ("timer: Move trace point to get proper index") Signed-off-by: Thomas Gleixner <tglx@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/87bjb0l7ha.ffs@fw13
2026-08-17sched_ext: Merge branch 'for-7.3-arena-args' into for-7.3Tejun Heo77-2073/+3486
Pull to receive the __arena argument conversion: 67f1f4a48c24 ("sched_ext: Pass kernel arena pointers to ops_cid callbacks") a8dc810968af ("sched_ext: Convert sub-cap kfuncs to __arena cmask arguments") a05c5b5cb5cf ("sched_ext: Convert scx_bpf_cid_override() to __arena array arguments") along with the bpf-next branch carrying the __arena argument support they depend on. Conflict in kernel/sched/ext/ext.c between: c384ab8a0b13 ("sched_ext: Move the config-off sub-cap kfunc stubs into sub.c") and: a8dc810968af ("sched_ext: Convert sub-cap kfuncs to __arena cmask arguments") which updated the stubs in their old ext.c location. Resolved by keeping ext.c without the stubs and applying the prototype conversion to the relocated stubs in sub.c. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-17Merge tag 'vfs-7.3-rc1.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfsLinus Torvalds1-7/+0
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
2026-08-17Merge tag 'vfs-7.3-rc1.kthread' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfsLinus Torvalds3-25/+36
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 ...
2026-08-17NFS/localio: issue IO inline when not in a memory-reclaim contextMike Snitzer1-0/+24
Every LOCALIO read and write is currently bounced through the dedicated !WQ_MEM_RECLAIM nfslocaliod_workqueue. That bounce is only actually required when the submitting context is a memory-reclaim context: LOCALIO issues IO directly into a stacked local filesystem (e.g. XFS) which may in turn flush its own !WQ_MEM_RECLAIM workqueue. Doing that from a WQ_MEM_RECLAIM worker (most importantly writeback's wb_workfn on bdi_wq) or an explicit PF_MEMALLOC reclaim task trips check_flush_dependency() and risks a forward-progress deadlock, which is why commit b9f5dd57f4a5 ("nfs/localio: use dedicated workqueues for filesystem read and write") introduced the intermediate workqueue. Outside of reclaim context -- ordinary application/task submission such as O_DIRECT or fsync-driven writeback -- the workqueue hop buys nothing and merely adds a context switch and scheduling latency per IO while discarding the NFS client's inherent application-context parallelism. Add current_is_workqueue_mem_reclaim(), which reports whether %current is a WQ_MEM_RECLAIM worker using the same predicate check_flush_dependency() warns on. Use it, together with the PF_MEMALLOC check, in the new nfs_local_defer_io() helper to decide per-IO whether nfs_local_do_read() and nfs_local_do_write() must defer to nfslocaliod_workqueue or may issue the IO inline. Buffered writeback continues to bounce (wb_workfn is a WQ_MEM_RECLAIM worker); O_DIRECT and app-context submission now run inline. Running nfs_local_call_write() inline is safe: it already saves and restores current->flags around the PF_LOCAL_THROTTLE|PF_MEMALLOC_NOIO it sets and scopes the file opener's creds. The async O_DIRECT completion path is likewise unaffected: when the underlying filesystem returns -EIOCBQUEUED, the kiocb ki_complete callback (nfs_local_read_aio_complete / nfs_local_write_aio_complete) can run in bottom-half context and so must still defer the pgio completion (nfs_local_pgio_release -> rpc_call_done) to nfsiod_workqueue via nfs_local_pgio_aio_complete(). That completion hop is independent of how the IO was submitted, and this change leaves it as-is; only the submission side stops unconditionally hopping through nfslocaliod_workqueue. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2026-08-17Merge tag 'vfs-7.3-rc1.binfmt' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfsLinus Torvalds2-2/+8
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 ...
2026-08-17Merge tags 'ipc-7.3-rc1.misc' and 'kernel-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfsLinus Torvalds1-1/+1
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
2026-08-17bpf: Distinguish function references in policy diagnosticsKumar Kartikeya Dwivedi1-2/+10
add_subprogs() rejects both BPF-to-BPF calls and BPF_PSEUDO_FUNC loads for unprivileged programs. The latter loads a subprogram address for use as a callback, but its Policy report currently describes it as a function call and suggests avoiding calls that the program does not contain. Select the operation and suggestion from the instruction kind. Preserve the existing call wording for BPF_PSEUDO_CALL, and describe BPF_PSEUDO_FUNC as a BPF function reference. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/bpf/d02e6a6d3b2dc43a207b8ba836ce62497b250dede9252e7409c5212201c794b7@mail.kernel.org Link: https://lore.kernel.org/bpf/20260816015746.2632990-14-memxor@gmail.com
2026-08-17bpf: Preserve source attribution without source textKumar Kartikeya Dwivedi1-4/+8
GCC emits BTF line records with a file name and line number, but leaves the source line string empty. bpf_diag_source() currently treats that empty string as if the complete line record were unavailable, so diagnostics fall back to an instruction number and discard the function, file, and line attribution. Print the available source location before deciding whether source context can be rendered. When source text is absent, omit only the source context and retain the diagnostic annotation and instruction context. Fixes: b9c5d822f677 ("bpf: Add source and instruction diagnostic context") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260816015746.2632990-12-memxor@gmail.com
2026-08-17bpf: Correct kfunc argument diagnosticsKumar Kartikeya Dwivedi2-13/+17
The Call Type Safety diagnostics mishandle three kfunc argument classes. BTF type ID 0 represents void, but btf_show_name() also uses zero to end type traversal. A pointer that resolves to void therefore loses its pointee name and is rendered as "()". End traversal directly for concrete terminal types, but resolve referenced types before testing for ID zero, and name the void terminal type explicitly. Format the complete parameter pointer type for nullable kfunc arguments, so void pointers are reported as (void *). Also add the missing structured report when an __szk memory-size argument is not a verifier-known constant. Describe the generic bpf_refcount_acquire() contract without deriving an object type from its void pointer prototype. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/668871823f90f69896d3db27b56db2f53e481162.camel@gmail.com Link: https://lore.kernel.org/bpf/20260816015746.2632990-7-memxor@gmail.com
2026-08-17bpf: Use canonical stack argument names in diagnosticsKumar Kartikeya Dwivedi1-1/+1
The main diagnostic identifies the first outgoing stack slot as stack argument 1 and the sixth function argument. The causal history instead labels the same value as stack arg6, making it look like a different slot. Render causal-history targets in the verifier's canonical stack-argument location form. The first outgoing slot is now shown as *(R11-8), matching reg_arg_name(), while the main diagnostic retains its fuller slot and ordinal description. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/eb1be5327d136b7e5bd6d68e76fef6de20c40790.camel@gmail.com Link: https://lore.kernel.org/bpf/20260816015746.2632990-6-memxor@gmail.com
2026-08-17bpf: Preserve R0 lineage across helper callsKumar Kartikeya Dwivedi1-1/+1
check_helper_call() clears all caller-saved registers before taking the diagnostic snapshot of R0. This records NOT_INIT as the old state for every helper return and loses the lineage of the value held in R0 before the call. bpf_diag_record_caller_saved() deliberately skips R0 because the paired modification scope is responsible for it. Open the R0 modification scope before clearing caller-saved registers, matching the kfunc, ld_abs, and subprogram call paths. Reported-by: Sashiko <sashiko-bot@kernel.org> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260815073833.A93A91F000E9@smtp.kernel.org Link: https://lore.kernel.org/bpf/48e6f021b89562f68850fe21ef8c78719819b04cf9c4e4f50bc791937d37ace8@mail.kernel.org Link: https://lore.kernel.org/bpf/20260816015746.2632990-4-memxor@gmail.com
2026-08-17bpf: Reject negative optlen in cgroup getsockopt hookJunseo Lim1-1/+1
A cgroup getsockopt BPF program can shrink ctx->optlen after the kernel getsockopt handler has run. The kernel-buffer variant, used by TCP_ZEROCOPY_RECEIVE, only rejects values larger than the original length. If BPF writes a negative optlen, that value is accepted and propagated back to the TCP getsockopt code. It can then be passed to copy_to_sockptr() as a size_t and trigger the hardened usercopy bytes > INT_MAX warning. Reject negative ctx.optlen in __cgroup_bpf_run_filter_getsockopt_kern(), matching the lower-bound validation already present in the sockptr-based getsockopt hook. Fixes: 9cacf81f8161 ("bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE") Reported-by: Sechang Lim <rhkrqnwk98@gmail.com> Signed-off-by: Junseo Lim <zirajs7@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/187a4d756275aaaee5d65eecb63c1477b3b66554.1786448307.git.zirajs7@gmail.com
2026-08-17bpf: Rewrite any fault prone load out of a mem or btf_id pointerDaniel Borkmann2-34/+28
bpf_convert_ctx_accesses() turns a BPF_LDX into a BPF_PROBE_MEM one by matching the type recorded for the insn against a list of exact pointer types. The list cannot keep up with the flag combinations the verifier produces, and a type which is missing from it ends up as a plain load without an exception table entry, so a bad address panics the kernel instead of being handled. Two such types exist today and are reachable: - PTR_TO_BTF_ID | PTR_UNTRUSTED | MEM_ALLOC | NON_OWN_REF - PTR_TO_BTF_ID | PTR_UNTRUSTED | MEM_RCU Rather than adding the two, just drop the list and state the property itself in the default case of the switch. This is a superset of what the list matched, the untrusted PTR_TO_MEM does not have to carry MEM_RDONLY for it anymore, and it stays in sync with the verifier side which uses the same match in save_aux_ptr_type() and reg_type_mismatch_ok(). Assert that a fault prone type which does not get the rewrite for whatever reason is rejected at load time rather than left to fault at runtime to catch any future cases. Fixes: 1b12171533a9 ("bpf: Mark direct ld of stashed bpf_{rb,list}_node as non-owning ref") Fixes: 6fcd486b3a0a ("bpf: Refactor RCU enforcement in the verifier.") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260814215301.709827-4-daniel@iogearbox.net
2026-08-17bpf: Reject a store through a fault prone pointerDaniel Borkmann1-1/+1
check_ptr_to_btf_access() allows the program to store before the default BTF access path gets to reject a non read access. ac65c710cc64 ("bpf: Reject writes through untrusted BTF pointers") closed that for a PTR_UNTRUSTED pointer, but a bare PTR_TO_BTF_ID may fault on a dereference just the same and is let through. A BPF_LDX gets the BPF_PROBE_MEM rewrite in bpf_convert_ctx_accesses() and a bad address is handled, but a BPF_STX does not and cannot, there is no probed store to rewrite. The store is emitted as a plain one without an exception table entry and a bad address panics the kernel. A bpf_qdisc program can reach this, bpf_qdisc_btf_struct_access() permits a write to Qdisc::limit and Qdisc::next_sched is a plain struct Qdisc pointer which the walk turns into the compat type: struct Qdisc *next = sch->next_sched; next->limit = 1000; BUG: kernel NULL pointer dereference, address: 0000000000000014 RIP: 0010:bpf_prog_c6e14e7f32c8e325_bpf_fifo_enqueue+0x3a/0x12b Code: [...] bf e8 03 00 00 <89> 7e 14 41 8b 7f 14 [...] Kernel panic - not syncing: Fatal exception in interrupt Fix by widen the check to bpf_may_fault_on_deref() so that it covers both. Fixes: 27ae7997a661 ("bpf: Introduce BPF_PROG_TYPE_STRUCT_OPS") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260814215301.709827-3-daniel@iogearbox.net
2026-08-17bpf: Treat a fault prone PTR_TO_MEM as a pointer type mismatchDaniel Borkmann1-0/+2
reg_type_mismatch_ok() enumerates the pointer types which must not silently share a BPF_LDX with a different one, since the type recorded for the insn drives a rewrite in bpf_convert_ctx_accesses(). f2362a57aeff ("bpf: allow void* cast using bpf_rdonly_cast()") added PTR_TO_MEM | MEM_RDONLY | PTR_UNTRUSTED as another type in need of one, namely the BPF_PROBE_MEM rewrite, but did not add it there. Fix it by adding the missing case to reg_type_mismatch_ok(), so that a PTR_TO_MEM which may fault on deref is not mismatch ok anymore. The triage in save_aux_ptr_type() then merges them. Fixes: f2362a57aeff ("bpf: allow void* cast using bpf_rdonly_cast()") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260814215301.709827-2-daniel@iogearbox.net
2026-08-17bpf: Keep fault protection when merging pointer typesDaniel Borkmann1-26/+23
When the same BPF_LDX instruction is reached through paths that yield different pointer types, save_aux_ptr_type() merges them into a single type which is later used by bpf_convert_ctx_accesses() to decide whether the load has to be rewritten into a BPF_PROBE_MEM one. Before f2362a57aeff ("bpf: allow void* cast using bpf_rdonly_cast()") the merge only accepted two PTR_TO_BTF_ID pointers and unconditionally fell back to PTR_TO_BTF_ID | PTR_UNTRUSTED, so the merged type was always one that gets the BPF_PROBE_MEM rewrite. However, the mentioned commit widened the merge to also cover a PTR_TO_MEM base and replaced the fallback by a union of the PTR_UNTRUSTED and MEM_RDONLY flags. A union of flags though cannot express the property the later rewrite is built upon, some examples: - PTR_TO_MEM merged with PTR_TO_BTF_ID | PTR_UNTRUSTED gets PTR_TO_MEM | PTR_UNTRUSTED but only the MEM_RDONLY variant is valid - PTR_TO_MEM merged with a plain PTR_TO_BTF_ID gets PTR_TO_MEM dropping the rewrite the latter type would have gotten - PTR_TO_MEM | MEM_RDONLY merged with a plain PTR_TO_BTF_ID gets PTR_TO_MEM | MEM_RDONLY which is not rewritten either since only its PTR_UNTRUSTED variant is In all three cases a program can take the unsafe path at runtime with a NULL or otherwise bad pointer and panic the kernel on the faulting load: BUG: kernel NULL pointer dereference, address: 0000000000000038 RIP: 0010:bpf_prog_77531a87032eeaf1_mixed_mem_btf_id_type+0x4b/0x65 Call Trace: <TASK> bpf_test_run+0x20b/0x460 bpf_prog_test_run_skb+0x650/0xbe0 __sys_bpf+0xb96/0x3140 __x64_sys_bpf+0x2c/0x40 do_syscall_64+0xba/0x590 Kernel panic - not syncing: Fatal exception in interrupt Note that the last two shapes have to be fixed right here, otherwise the merged type retains nothing which marks the load as fault prone, thus no rule in bpf_convert_ctx_accesses() can recover it. Fix it by normalizing the merged type instead. Reuse it in is_load_acq_unsafe() to avoid open coding, and trim the overly verbose comment which is more of an implementation detail of bpf_convert_ctx_accesses() anyway. Fixes: f2362a57aeff ("bpf: allow void* cast using bpf_rdonly_cast()") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20260814215301.709827-1-daniel@iogearbox.net
2026-08-16bpf: Check pointer type for all atomic RMW pathsYiyang Chen1-5/+3
Atomic RMW verification records an instruction pointer type only when the current destination is PTR_TO_ARENA. A second path can therefore reach the same instruction with an ordinary pointer without comparing it against the saved arena type. The post-verification fixup uses the saved type to rewrite the instruction to BPF_PROBE_ATOMIC for every path. Record the actual destination type for all atomic RMW paths so the existing mismatch check rejects incompatible uses of one instruction. Fixes: d503a04f8bc0 ("bpf: Add support for certain atomics in bpf_arena to x86 JIT") Signed-off-by: Yiyang Chen <chenyy23@mails.tsinghua.edu.cn> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://patch.msgid.link/20260816-bpf-next-038-mixed-atomic-v1-v2-1-4644c1886dbc@mails.tsinghua.edu.cn Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-16Merge tag 'sched_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+2
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
2026-08-16Merge tag 'perf_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-31/+44
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
2026-08-15sched_ext: Drop the dead SCX_DEQ_CORE_SCHED_EXEC test in dequeue_task_scx()Tejun Heo1-2/+2
dequeue_task_scx() masks SCX_DEQ_CORE_SCHED_EXEC out of the SCX_DEQ_SCHED_CHANGE decision, but the test can never fire: the incoming flags are an int of generic DEQUEUE_* bits while the flag is bit 32, and the core-sched execute path never goes through class dequeue anyway - set_next_task_scx() calls ops_dequeue() with the flag directly. The test was live when the SCX_DEQ_SCHED_CHANGE computation sat in ops_dequeue() and became dead when 03f5304aad0f ("sched_ext: Pass full dequeue flags to ops.quiescent()") moved the computation here. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Make core-sched task ordering hierarchy-awareTejun Heo2-8/+35
With sub-schedulers, tasks of different schedulers routinely share rqs and SMT siblings, but scx_prio_less() consults ops.core_sched_before() only when both tasks belong to the same scheduler. Every pair spanning two schedulers falls back to the default ordering, so no scheduler can express ordering across a scheduler boundary, including a root over its sub-schedulers' tasks. Order a pair spanning schedulers by the nearest common ancestor that implements ops.core_sched_before(): both tasks are in its subtree, making this the one op where a scheduler is called on tasks it delegated to its sub-schedulers and may not be scheduling anymore. Same-scheduler pairs keep using the owning scheduler's op so a parent never orders inside a subtree it delegated. The op is skipped when the deciding scheduler is bypassing on either task's CPU. Update scx_qmap to fall back to the kernel's default ordering when handed a delegated task it has no task_ctx for. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Use runnable_at for the default core-sched task orderingTejun Heo1-80/+25
The default core-sched ordering runs the longest waiting task first by comparing p->scx.core_sched_at stamps. The stamp is maintained under two rules. touch_core_sched() stamps when a task starts waiting for a CPU and when its slice runs out. If the scheduler implements ops.core_sched_before(), touch_core_sched_dispatch() re-stamps on every dispatch. A comparison can see one stamp taken under each rule, which isn't a meaningful ordering. The dispatch rule also buys little - it only aligns bypass-mode comparisons with the local DSQ order. Multiple schedulers make the mixed comparisons more common. Wait time is what p->scx.runnable_at already tracks for the stall watchdog. Delete core_sched_at with both touch functions and compare runnable_at in the scx_prio_less() fallback. runnable_at is refreshed only on enqueue and goes stale while a task keeps occupying its CPU. Instead of re-stamping, order a running task after every waiting task as it is the most recently serviced. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Fix inverted ops.core_sched_before() invocationTejun Heo1-2/+8
scx_prio_less() implements prio_less() semantics - %true means that @a is the lower priority and should run after @b. ops.core_sched_before() is documented to return %true when @a should run before @b. scx_prio_less() returns the op's value as-is, inverting the documented semantics at runtime. Call the op with the arguments swapped. scx_qmap followed the wiring instead of the documentation and returned %true for the younger task, so the two inversions canceled out and it behaved as intended. Flip its comparison to match. scx_qmap is likely the only current user in or out of the kernel tree. Any scheduler written the same way needs the same flip, while schedulers following the documentation are fixed by this change. Fixes: 7b0888b7cc19 ("sched_ext: Implement core-sched support") Cc: stable@vger.kernel.org # v6.12+ Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Move the config-off sub-cap kfunc stubs into sub.cTejun Heo2-29/+33
The EOPNOTSUPP stubs for the sub-cap kfuncs live in ext.c under #ifndef CONFIG_EXT_SUB_SCHED while the real definitions live in sub.c. Move the stubs into sub.c so all sub kfunc definitions live in one file. Pure code move, no functional change. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-16futex: Fix race on the initial mm->futex.phash.ref allocationHyunwoo Kim1-6/+10
futex_hash_allocate() allocates mm->futex.phash.ref without any locking. Commit d9b05321e21e ("futex: Move futex_hash_free() back to __mmput()") moved the allocation here and assumed that the process has just a single thread at this point. Commit ee9dce44362b ("futex: Drop CLONE_THREAD requirement for private default hash alloc") widened need_futex_hash_allocate_default() to cover any CLONE_VM clone, but left out vfork because the parent is suspended and cannot race. That no longer holds once vfork is nested. If a vfork child calls vfork again and is then killed with SIGKILL, the parent is released from its vfork wait and runs concurrently with the grandchild in the same mm. Neither of them went through futex_hash_allocate_default(). When both call prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_SET_SLOTS) at the same time, each one sees mm->futex.phash.ref as NULL and stores its own percpu counter. Only the last store survives. The counter stored first is no longer reachable from the mm, so the references on it are not seen by __futex_ref_atomic_end(). A private hash that still has references is then considered dead and freed, and a task that still holds one of its buckets writes into freed memory in futex_q_lock(). Store the counter once with cmpxchg() and let the loser free_percpu() its own. The initial reference has to be taken before the store, otherwise another task can install a private hash while the counter is still 0. Fixes: d9b05321e21e ("futex: Move futex_hash_free() back to __mmput()") Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/ansrpP4ImE1MaBY9@v4bel
2026-08-16futex: Clean up the redundant exit/exec functionsThomas Gleixner3-29/+20
futex_exit_release() and futex_exec_release() are identical now. That means also exit_mm_release() and exec_mm_release() are identical. Consolidate the whole lot and remove the redundant copies. Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Kyle Zeng <kylebot@openai.com> Acked-by: Peter Zijlstra <peterz@infradead.org>
2026-08-16futex/pi: Plug private futex exec() raceThomas Gleixner2-23/+53
The check for private futexes whether the waiter's mm, which is stored in the futex_key and copied into the pi_state, is the same as the owner's mm is not sufficient for exec(). exec() has a gap where the mm check fails to give the correct answer: exec() ... exec_release_mm() futex_exec_release() tsk::futex::exit_state = EXITING; cleanup_robust_list(); 1) tsk::futex::exit_state = OK; ... old_mm = tsk::mm; 2) tsk::mm = ->mm; Between #1 and #2 the check for the mm is wrong as that mm is about to be swapped out and eventually freed. Plug this gap by: 1) Setting tsk::futex::exit_state to FUTEX_STATE_DEAD in futex_exec_release() 2) Setting tsk::futex::exit_state to FUTEX_STATE_OK after the mm has been switched. From a futex point of view the task is dead after it finished the robust list cleanup up to the point where it sets the state to OK again. Fixes: 80367ad01d93 ("futex: Add basic infrastructure for local task local hash") Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Kyle Zeng <kylebot@openai.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org
2026-08-15bpf: Add ksock kfuncsMahe Tardy1-0/+3
Add BPF kfuncs that allow BPF LSM programs to create and use sockets for sending data. This provides a mechanism for BPF programs to emit telemetry. For this first patch set, it's restricted to SOCK_DGRAM socket types with IPPROTO_UDP protocol but could be easily extended to SOCK_STREAM and IPPROTO_TCP in the future. The API consists of five kfuncs: bpf_ksock_create() - Create a socket (sleepable) bpf_ksock_connect() - Connect socket to remote address (sleepable) bpf_ksock_send() - Send data through the socket (sleepable) bpf_ksock_acquire() - Acquire a reference to a socket context bpf_ksock_release() - Release a reference (cleanup via queue_rcu_work since sock_release sleeps) The setup kfuncs bpf_ksock_create, bpf_ksock_connect, can be called from SYSCALL programs only. While bpf_ksock_acquire, bpf_ksock_release and bpf_ksock_send can be called from SYSCALL and LSM programs. The implementation follows the established kfunc lifecycle pattern (create/acquire/release with refcounting, kptr map storage, dtor registration). The kernel socket is wrapped in a refcounted bpf_ksock struct. Cleanup is deferred via queue_rcu_work() because sock_release() may sleep. The kfuncs are only compiled when CONFIG_INET is enabled, as they specifically support AF_INET and AF_INET6 sockets. The socket operations go through the expected LSM hooks instead of by-passing them like many kernel sockets since those are created by BPF programs and thus system users. Thus, the bpf_ksock_send() kfunc, which is exposed to LSM progs has a verifier filter protection to avoid recursion so that the whole bpf_kfunc_set kfunc set cannot be called in a program attached to security_socket_sendmsg(). Also, because of the LSM checks, we prevent the use of the kfuncs from asynchronous workqueue as the current value would then be invalid. In bpf_ksock_create(), we copy the arg values to avoid TOCTOU races since the kfunc can sleep and the arg values could be stored in a map that could be re-written by BPF progs or even userspace programs if the map is mmaped. Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20260813110540.103550-3-mahe.tardy@gmail.com
2026-08-15bpf: Report Policy helper and kfunc errorsKumar Kartikeya Dwivedi3-1/+48
Augment selected helper and kfunc allowability failures with Policy reports. These reports explain which requested operation is forbidden and why, without adding path history for non-path-dependent policy checks. Cover unprivileged bpf2bpf and kfunc use, helper program-type restrictions, GPL-only helpers, helper-specific allow callbacks, kfunc allowability, and destructive kfunc capability checks. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://patch.msgid.link/20260815064612.378577-15-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-15bpf: Report Program Structure CFG errorsKumar Kartikeya Dwivedi4-0/+73
Augment selected whole-program and subprogram CFG validation failures with Program Structure reports. These errors are structural rather than path-dependent, so the reports focus on source and instruction context instead of causal history. Cover direct and indirect jumps outside the program or current subprogram, unprivileged backedges, missing and out-of-range jump tables, targets in the second half of an ldimm64, unreachable instructions, subprogram fallthrough, and recursive bpf2bpf call graph edges. Format long jump-range reasons directly in diagnostics.c, and keep the fallthrough suggestion aligned with the verifier check by suggesting exit or explicit jumps. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://patch.msgid.link/20260815064612.378577-14-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-15bpf: Report Execution Context Safety errorsKumar Kartikeya Dwivedi3-1/+217
Augment selected sleepability and critical-section failures with Execution Context Safety reports. Keep the existing verifier messages and add source context, path history, and suggestions tied to the active context. Use the context history recorded earlier to anchor causal paths to lock, IRQ, RCU, and preempt regions instead of unrelated register updates. Cover global calls while holding a lock, sleepable global function calls, sleepable helpers, sleepable kfunc calls from disallowed contexts, operations that exit while a context is still active, and unmatched context exits. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://patch.msgid.link/20260815064612.378577-13-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-15bpf: Report Call Type Safety argument errorsKumar Kartikeya Dwivedi3-56/+387
Augment selected helper and kfunc argument-contract failures with Call Type Safety reports. Keep the existing terse verifier messages and add reason, source context, causal register or stack-argument history, and targeted suggestions. Cover helper register-type mismatch, helper and kfunc non-NULL pointer requirements, release-helper ownership requirements, scalar and constant kfunc arguments, trusted and RCU pointer contracts, kfunc memory arguments, memory/length pairs, refcounted kptrs, constant strings, and IRQ flag stack arguments. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://patch.msgid.link/20260815064612.378577-12-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>