Commit Graph

50913 Commits

Author SHA1 Message Date
Linus Torvalds
ff661eeee2 Merge tag 'cgroup-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:

 - cpuset changes:

    - Continue separating v1 and v2 implementations by moving more
      v1-specific logic into cpuset-v1.c

    - Improve partition handling. Sibling partitions are no longer
      invalidated on cpuset.cpus conflict, cpuset.cpus changes no longer
      fail in v2, and effective_xcpus computation is made consistent

    - Fix partition effective CPUs overlap that caused a warning on
      cpuset removal when sibling partitions shared CPUs

 - Increase the maximum cgroup subsystem count from 16 to 32 to
   accommodate future subsystem additions

 - Misc cleanups and selftest improvements including switching to
   css_is_online() helper, removing dead code and stale documentation
   references, using lockdep_assert_cpuset_lock_held() consistently, and
   adding polling helpers for asynchronously updated cgroup statistics

* tag 'cgroup-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
  cpuset: fix overlap of partition effective CPUs
  cgroup: increase maximum subsystem count from 16 to 32
  cgroup: Remove stale cpu.rt.max reference from documentation
  cpuset: replace direct lockdep_assert_held() with lockdep_assert_cpuset_lock_held()
  cgroup/cpuset: Move the v1 empty cpus/mems check to cpuset1_validate_change()
  cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflict
  cgroup/cpuset: Don't fail cpuset.cpus change in v2
  cgroup/cpuset: Consistently compute effective_xcpus in update_cpumasks_hier()
  cgroup/cpuset: Streamline rm_siblings_excl_cpus()
  cpuset: remove dead code in cpuset-v1.c
  cpuset: remove v1-specific code from generate_sched_domains
  cpuset: separate generate_sched_domains for v1 and v2
  cpuset: move update_domain_attr_tree to cpuset_v1.c
  cpuset: add cpuset1_init helper for v1 initialization
  cpuset: add cpuset1_online_css helper for v1-specific operations
  cpuset: add lockdep_assert_cpuset_lock_held helper
  cpuset: Remove unnecessary checks in rebuild_sched_domains_locked
  cgroup: switch to css_is_online() helper
  selftests: cgroup: Replace sleep with cg_read_key_long_poll() for waiting on nr_dying_descendants
  selftests: cgroup: make test_memcg_sock robust against delayed sock stats
  ...
2026-02-11 13:20:50 -08:00
Linus Torvalds
9bdc64892d Merge tag 'wq-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:

 - Rework the rescuer to process work items one-by-one instead of
   slurping all pending work items in a single pass.

   As there is only one rescuer per workqueue, a single long-blocking
   work item could cause high latency for all tasks queued behind it,
   even after memory pressure is relieved and regular kworkers become
   available to service them.

 - Add CONFIG_BOOTPARAM_WQ_STALL_PANIC build-time option and
   workqueue.panic_on_stall_time parameter for time-based stall panic,
   giving systems more control over workqueue stall handling.

 - Replace BUG_ON() with panic() in the stall panic path for clearer
   intent and more informative output.

* tag 'wq-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: replace BUG_ON with panic in panic_on_wq_watchdog
  workqueue: add time-based panic for stalls
  workqueue: add CONFIG_BOOTPARAM_WQ_STALL_PANIC option
  workqueue: Process extra works in rescuer on memory pressure
  workqueue: Process rescuer work items one-by-one using a cursor
  workqueue: Make send_mayday() take a PWQ argument directly
2026-02-11 13:13:32 -08:00
Thomas Gleixner
1e83ccd592 sched/mmcid: Don't assume CID is CPU owned on mode switch
Shinichiro reported a KASAN UAF, which is actually an out of bounds access
in the MMCID management code.

   CPU0						CPU1
   						T1 runs in userspace
   T0: fork(T4) -> Switch to per CPU CID mode
         fixup() set MM_CID_TRANSIT on T1/CPU1
   T4 exit()
   T3 exit()
   T2 exit()
						T1 exit() switch to per task mode
						 ---> Out of bounds access.

As T1 has not scheduled after T0 set the TRANSIT bit, it exits with the
TRANSIT bit set. sched_mm_cid_remove_user() clears the TRANSIT bit in
the task and drops the CID, but it does not touch the per CPU storage.
That's functionally correct because a CID is only owned by the CPU when
the ONCPU bit is set, which is mutually exclusive with the TRANSIT flag.

Now sched_mm_cid_exit() assumes that the CID is CPU owned because the
prior mode was per CPU. It invokes mm_drop_cid_on_cpu() which clears the
not set ONCPU bit and then invokes clear_bit() with an insanely large
bit number because TRANSIT is set (bit 29).

Prevent that by actually validating that the CID is CPU owned in
mm_drop_cid_on_cpu().

Fixes: 007d84287c ("sched/mmcid: Drop per CPU CID immediately when switching to per task mode")
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Cc: stable@vger.kernel.org
Closes: https://lore.kernel.org/aYsZrixn9b6s_2zL@shinmob
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-11 12:59:56 -08:00
Masami Hiramatsu (Google)
804c4a2209 tracing: Reset last_boot_info if ring buffer is reset
Commit 32dc004252 ("tracing: Reset last-boot buffers when reading
out all cpu buffers") resets the last_boot_info when user read out
all data via trace_pipe* files. But it is not reset when user
resets the buffer from other files. (e.g. write `trace` file)

Reset it when the corresponding ring buffer is reset too.

Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/177071302364.2293046.17895165659153977720.stgit@mhiramat.tok.corp.google.com
Fixes: 32dc004252 ("tracing: Reset last-boot buffers when reading out all cpu buffers")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-11 10:49:48 -05:00
Masami Hiramatsu (Google)
f844282dee tracing: Fix to set write permission to per-cpu buffer_size_kb
Since the per-cpu buffer_size_kb file is writable for changing
per-cpu ring buffer size, the file should have the write access
permission.

Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/177071301597.2293046.11683339475076917920.stgit@mhiramat.tok.corp.google.com
Fixes: 21ccc9cd72 ("tracing: Disable "other" permission bits in the tracefs files")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-11 10:48:44 -05:00
Petr Mladek
9abbecf408 Merge branch 'for-6.20' into for-linus 2026-02-11 10:14:35 +01:00
Linus Torvalds
192c015940 Merge tag 'powerpc-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates for 7.0

 - Implement masked user access

 - Add bpf support for internal only per-CPU instructions and inline the
   bpf_get_smp_processor_id() and bpf_get_current_task() functions

 - Fix pSeries MSI-X allocation failure when quota is exceeded

 - Fix recursive pci_lock_rescan_remove locking in EEH event handling

 - Support tailcalls with subprogs & BPF exceptions on 64bit

 - Extend "trusted" keys to support the PowerVM Key Wrapping Module
   (PKWM)

Thanks to Abhishek Dubey, Christophe Leroy, Gaurav Batra, Guangshuo Li,
Jarkko Sakkinen, Mahesh Salgaonkar, Mimi Zohar, Miquel Sabaté Solà, Nam
Cao, Narayana Murty N, Nayna Jain, Nilay Shroff, Puranjay Mohan, Saket
Kumar Bhaskar, Sourabh Jain, Srish Srinivasan, and Venkat Rao Bagalkote.

* tag 'powerpc-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (27 commits)
  powerpc/pseries: plpks: export plpks_wrapping_is_supported
  docs: trusted-encryped: add PKWM as a new trust source
  keys/trusted_keys: establish PKWM as a trusted source
  pseries/plpks: add HCALLs for PowerVM Key Wrapping Module
  pseries/plpks: expose PowerVM wrapping features via the sysfs
  powerpc/pseries: move the PLPKS config inside its own sysfs directory
  pseries/plpks: fix kernel-doc comment inconsistencies
  powerpc/smp: Add check for kcalloc() failure in parse_thread_groups()
  powerpc: kgdb: Remove OUTBUFMAX constant
  powerpc64/bpf: Additional NVR handling for bpf_throw
  powerpc64/bpf: Support exceptions
  powerpc64/bpf: Add arch_bpf_stack_walk() for BPF JIT
  powerpc64/bpf: Avoid tailcall restore from trampoline
  powerpc64/bpf: Support tailcalls with subprogs
  powerpc64/bpf: Moving tail_call_cnt to bottom of frame
  powerpc/eeh: fix recursive pci_lock_rescan_remove locking in EEH event handling
  powerpc/pseries: Fix MSI-X allocation failure when quota is exceeded
  powerpc/iommu: bypass DMA APIs for coherent allocations for pre-mapped memory
  powerpc64/bpf: Inline bpf_get_smp_processor_id() and bpf_get_current_task/_btf()
  powerpc64/bpf: Support internal-only MOV instruction to resolve per-CPU addrs
  ...
2026-02-10 21:46:12 -08:00
Breno Leitao
60325c27d3 printk: Add execution context (task name/CPU) to printk_info
Extend struct printk_info to include the task name, pid, and CPU
number where printk messages originate. This information is captured
at vprintk_store() time and propagated through printk_message to
nbcon_write_context, making it available to nbcon console drivers.

This is useful for consoles like netconsole that want to include
execution context in their output, allowing correlation of messages
with specific tasks and CPUs regardless of where the console driver
actually runs.

The feature is controlled by CONFIG_PRINTK_EXECUTION_CTX, which is
automatically selected by CONFIG_NETCONSOLE_DYNAMIC. When disabled,
the helper functions compile to no-ops with no overhead.

Suggested-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Link: https://patch.msgid.link/20260206-nbcon-v7-1-62bda69b1b41@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-10 19:51:56 -08:00
Linus Torvalds
57cb845067 Merge tag 'x86_paravirt_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt updates from Borislav Petkov:

 - A nice cleanup to the paravirt code containing a unification of the
   paravirt clock interface, taming the include hell by splitting the
   pv_ops structure and removing of a bunch of obsolete code (Juergen
   Gross)

* tag 'x86_paravirt_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/paravirt: Use XOR r32,r32 to clear register in pv_vcpu_is_preempted()
  x86/paravirt: Remove trailing semicolons from alternative asm templates
  x86/pvlocks: Move paravirt spinlock functions into own header
  x86/paravirt: Specify pv_ops array in paravirt macros
  x86/paravirt: Allow pv-calls outside paravirt.h
  objtool: Allow multiple pv_ops arrays
  x86/xen: Drop xen_mmu_ops
  x86/xen: Drop xen_cpu_ops
  x86/xen: Drop xen_irq_ops
  x86/paravirt: Move pv_native_*() prototypes to paravirt.c
  x86/paravirt: Introduce new paravirt-base.h header
  x86/paravirt: Move paravirt_sched_clock() related code into tsc.c
  x86/paravirt: Use common code for paravirt_steal_clock()
  riscv/paravirt: Use common code for paravirt_steal_clock()
  loongarch/paravirt: Use common code for paravirt_steal_clock()
  arm64/paravirt: Use common code for paravirt_steal_clock()
  arm/paravirt: Use common code for paravirt_steal_clock()
  sched: Move clock related paravirt code to kernel/sched
  paravirt: Remove asm/paravirt_api_clock.h
  x86/paravirt: Move thunk macros to paravirt_types.h
  ...
2026-02-10 19:01:45 -08:00
Linus Torvalds
f1c538ca81 Merge tag 'timers-vdso-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull VDSO updates from Thomas Gleixner:

 - Provide the missing 64-bit variant of clock_getres()

   This allows the extension of CONFIG_COMPAT_32BIT_TIME to the vDSO and
   finally the removal of 32-bit time types from the kernel and UAPI.

 - Remove the useless and broken getcpu_cache from the VDSO

   The intention was to provide a trivial way to retrieve the CPU number
   from the VDSO, but as the VDSO data is per process there is no way to
   make it work.

 - Switch get/put_unaligned() from packed struct to memcpy()

   The packed struct violates strict aliasing rules which requires to
   pass -fno-strict-aliasing to the compiler. As this are scalar values
   __builtin_memcpy() turns them into simple loads and stores

 - Use __typeof_unqual__() for __unqual_scalar_typeof()

   The get/put_unaligned() changes triggered a new sparse warning when
   __beNN types are used with get/put_unaligned() as sparse builds add a
   special 'bitwise' attribute to them which prevents sparse to evaluate
   the Generic in __unqual_scalar_typeof().

   Newer sparse versions support __typeof_unqual__() which avoids the
   problem, but requires a recent sparse install. So this adds a sanity
   check to sparse builds, which validates that sparse is available and
   capable of handling it.

 - Force inline __cvdso_clock_getres_common()

   Compilers sometimes un-inline agressively, which results in function
   call overhead and problems with automatic stack variable
   initialization.

   Interestingly enough the force inlining results in smaller code than
   the un-inlined variant produced by GCC when optimizing for size.

* tag 'timers-vdso-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  vdso/gettimeofday: Force inlining of __cvdso_clock_getres_common()
  x86/percpu: Make CONFIG_USE_X86_SEG_SUPPORT work with sparse
  compiler: Use __typeof_unqual__() for __unqual_scalar_typeof()
  powerpc/vdso: Provide clock_getres_time64()
  tools headers: Remove unneeded ignoring of warnings in unaligned.h
  tools headers: Update the linux/unaligned.h copy with the kernel sources
  vdso: Switch get/put_unaligned() from packed struct to memcpy()
  parisc: Inline a type punning version of get_unaligned_le32()
  vdso: Remove struct getcpu_cache
  MIPS: vdso: Provide getres_time64() for 32-bit ABIs
  arm64: vdso32: Provide clock_getres_time64()
  ARM: VDSO: Provide clock_getres_time64()
  ARM: VDSO: Patch out __vdso_clock_getres() if unavailable
  x86/vdso: Provide clock_getres_time64() for x86-32
  selftests: vDSO: vdso_test_abi: Add test for clock_getres_time64()
  selftests: vDSO: vdso_test_abi: Use UAPI system call numbers
  selftests: vDSO: vdso_config: Add configurations for clock_getres_time64()
  vdso: Add prototype for __vdso_clock_getres_time64()
2026-02-10 17:02:23 -08:00
Linus Torvalds
353a7e8a69 Merge tag 'timers-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer core updates from Thomas Gleixner:

 - Inline timecounter_cyc2time() as that is now used in the networking
   hotpath. Inlining it significantly improves performance.

 - Optimize the tick dependency check in case that the tracepoint is
   disabled, which improves the hotpath performance in the tick
   management code, which is a hotpath on transitions in and out of
   idle.

 - The usual cleanups and improvements

* tag 'timers-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time/kunit: Document handling of negative years of is_leap()
  tick/nohz: Optimize check_tick_dependency() with early return
  time/sched_clock: Use ACCESS_PRIVATE() to evaluate hrtimer::function
  hrtimer: Drop _tv64() helpers
  hrtimer: Remove public definition of HIGH_RES_NSEC
  hrtimer: Remove unused resolution constants
  time/timecounter: Inline timecounter_cyc2time()
2026-02-10 16:41:59 -08:00
Linus Torvalds
3381d7b2b3 Merge tag 'irq-msi-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull MSI updates from Thomas Gleixner:
 "Updates for the [PCI] MSI subsystem:

   - Add interrupt redirection infrastructure

     Some PCI controllers use a single demultiplexing interrupt for the
     MSI interrupts of subordinate devices.

     This prevents setting the interrupt affinity of device interrupts,
     which causes device interrupts to be delivered to a single CPU.
     That obviously is counterproductive for multi-queue devices and
     interrupt balancing.

     To work around this limitation the new infrastructure installs a
     dummy irq_set_affinity() callback which captures the affinity mask
     and picks a redirection target CPU out of the mask.

     When the PCI controller demultiplexes the interrupts it invokes a
     new handling function in the core, which either runs the interrupt
     handler in the context of the target CPU or delegates it to
     irq_work on the target CPU.

   - Utilize the interrupt redirection mechanism in the PCI DWC host
     controller driver.

     This allows affinity control for the subordinate device MSI
     interrupts instead of being randomly executed on the CPU which runs
     the demultiplex handler.

   - Replace the binary 64-bit MSI flag with a DMA mask

     Some PCI devices have PCI_MSI_FLAGS_64BIT in the MSI capability,
     but implement less than 64 address bits. This breaks on platforms
     where such a device is assigned an MSI address higher than what's
     supported.

     With the binary 64-bit flag there is no other choice than disabling
     64-bit MSI support which leaves the device disfunctional.

     By using a DMA mask the address limit of a device can be described
     correctly which provides support for the above scenario.

   - Make use of the DMA mask based address limit in the hda/intel and
     radeon drivers to enable them on affected platforms

   - The usual small cleanups and improvements"

* tag 'irq-msi-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ALSA: hda/intel: Make MSI address limit based on the device DMA limit
  drm/radeon: Make MSI address limit based on the device DMA limit
  PCI/MSI: Check the device specific address mask in msi_verify_entries()
  PCI/MSI: Convert the boolean no_64bit_msi flag to a DMA address mask
  genirq/redirect: Prevent writing MSI message on affinity change
  PCI/MSI: Unmap MSI-X region on error
  genirq: Update effective affinity for redirected interrupts
  PCI: dwc: Enable MSI affinity support
  PCI: dwc: Code cleanup
  genirq: Add interrupt redirection infrastructure
  genirq/msi: Correct kernel-doc in <linux/msi.h>
2026-02-10 16:30:29 -08:00
Linus Torvalds
66bbe4a8ed Merge tag 'irq-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq core updates from Thomas Gleixner:
 "Updates for the interrupt core subsystem:

   - Remove the interrupt timing infrastructure

     This was added seven years ago to be used for power management
     purposes, but that integration never happened.

   - Clean up the remaining setup_percpu_irq() users

     The memory allocator is available when interrupts can be requested
     so there is not need for static irq_action. Move the remaining
     users to request_percpu_irq() and delete the historical cruft.

   - Warn when interrupt flag inconsistencies are detected in
     request*_irq().

     Inconsistent flags can lead to hard to diagnose malfunction. The
     fallout of this new warning has been addressed in next and the
     fixes are coming in via the maintainer trees and the tip
     irq/cleanup pull requests.

   - Invoke affinity notifier when CPU hotplug breaks affinity

     Otherwise the code using the notifier misses the affinity change
     and operates on stale information.

   - The usual cleanups and improvements"

* tag 'irq-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/proc: Replace snprintf with strscpy in register_handler_proc
  genirq/cpuhotplug: Notify about affinity changes breaking the affinity mask
  genirq: Move clear of kstat_irqs to free_desc()
  genirq: Warn about using IRQF_ONESHOT without a threaded handler
  irqdomain: Fix up const problem in irq_domain_set_name()
  genirq: Remove setup_percpu_irq()
  clocksource/drivers/mips-gic-timer: Move GIC timer to request_percpu_irq()
  MIPS: Move IP27 timer to request_percpu_irq()
  MIPS: Move IP30 timer to request_percpu_irq()
  genirq: Remove __request_percpu_irq() helper
  genirq: Remove IRQ timing tracking infrastructure
2026-02-10 13:39:37 -08:00
Linus Torvalds
36ae1c45b2 Merge tag 'sched-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "Scheduler Kconfig space updates:

   - Further consolidate configurable preemption modes (Peter Zijlstra)

     Reduce the number of architectures that are allowed to offer
     PREEMPT_NONE and PREEMPT_VOLUNTARY, reducing the number of
     preemption models from four to just two: 'full' and 'lazy' on
     up-to-date architectures (arm64, loongarch, powerpc, riscv, s390,
     x86).

     None and voluntary are only available as legacy features on
     platforms that don't implement lazy preemption yet, or which don't
     even support preemption.

     The goal is to eventually remove cond_resched() and voluntary
     preemption altogether.

  RSEQ based 'scheduler time slice extension' support (Thomas Gleixner
  and Peter Zijlstra):

  This allows a thread to request a time slice extension when it enters
  a critical section to avoid contention on a resource when the thread
  is scheduled out inside of the critical section.

   - Add fields and constants for time slice extension
   - Provide static branch for time slice extensions
   - Add statistics for time slice extensions
   - Add prctl() to enable time slice extensions
   - Implement sys_rseq_slice_yield()
   - Implement syscall entry work for time slice extensions
   - Implement time slice extension enforcement timer
   - Reset slice extension when scheduled
   - Implement rseq_grant_slice_extension()
   - entry: Hook up rseq time slice extension
   - selftests: Implement time slice extension test
   - Allow registering RSEQ with slice extension
   - Move slice_ext_nsec to debugfs
   - Lower default slice extension
   - selftests/rseq: Add rseq slice histogram script

  Scheduler performance/scalability improvements:

   - Update rq->avg_idle when a task is moved to an idle CPU, which
     improves the scalability of various workloads (Shubhang Kaushik)

   - Reorder fields in 'struct rq' for better caching (Blake Jones)

   - Fair scheduler SMP NOHZ balancing code speedups (Shrikanth Hegde):
      - Move checking for nohz cpus after time check
      - Change likelyhood of nohz.nr_cpus
      - Remove nohz.nr_cpus and use weight of cpumask instead

   - Avoid false sharing for sched_clock_irqtime (Wangyang Guo)

   - Cleanups (Yury Norov):
      - Drop useless cpumask_empty() in find_energy_efficient_cpu()
      - Simplify task_numa_find_cpu()
      - Use cpumask_weight_and() in sched_balance_find_dst_group()

  DL scheduler updates:

   - Add a deadline server for sched_ext tasks (by Andrea Righi and Joel
     Fernandes, with fixes by Peter Zijlstra)

  RT scheduler updates:

   - Skip currently executing CPU in rto_next_cpu() (Chen Jinghuang)

  Entry code updates and performance improvements (Jinjie Ruan)

  This is part of the scheduler tree in this cycle due to inter-
  dependencies with the RSEQ based time slice extension work:

    - Remove unused syscall argument from syscall_trace_enter()
    - Rework syscall_exit_to_user_mode_work() for architecture reuse
    - Add arch_ptrace_report_syscall_entry/exit()
    - Inline syscall_exit_work() and syscall_trace_enter()

  Scheduler core updates (Peter Zijlstra):

   - Rework sched_class::wakeup_preempt() and rq_modified_*()
   - Avoid rq->lock bouncing in sched_balance_newidle()
   - Rename rcu_dereference_check_sched_domain() =>
            rcu_dereference_sched_domain()
   - <linux/compiler_types.h>: Add the __signed_scalar_typeof() helper

  Fair scheduler updates/refactoring (Peter Zijlstra and Ingo Molnar):

   - Fold the sched_avg update
   - Change rcu_dereference_check_sched_domain() to rcu-sched
   - Switch to rcu_dereference_all()
   - Remove superfluous rcu_read_lock()
   - Limit hrtick work
   - Join two #ifdef CONFIG_FAIR_GROUP_SCHED blocks
   - Clean up comments in 'struct cfs_rq'
   - Separate se->vlag from se->vprot
   - Rename cfs_rq::avg_load to cfs_rq::sum_weight
   - Rename cfs_rq::avg_vruntime to ::sum_w_vruntime & helper functions
   - Introduce and use the vruntime_cmp() and vruntime_op() wrappers for
     wrapped-signed aritmetics
   - Sort out 'blocked_load*' namespace noise

  Scheduler debugging code updates:

   - Export hidden tracepoints to modules (Gabriele Monaco)

   - Convert copy_from_user() + kstrtouint() to kstrtouint_from_user()
     (Fushuai Wang)

   - Add assertions to QUEUE_CLASS (Peter Zijlstra)

   - hrtimer: Fix tracing oddity (Thomas Gleixner)

  Misc fixes and cleanups:

   - Re-evaluate scheduling when migrating queued tasks out of throttled
     cgroups (Zicheng Qu)

   - Remove task_struct->faults_disabled_mapping (Christoph Hellwig)

   - Fix math notation errors in avg_vruntime comment (Zhan Xusheng)

   - sched/cpufreq: Use %pe format for PTR_ERR() printing
     (zenghongling)"

* tag 'sched-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  sched: Re-evaluate scheduling when migrating queued tasks out of throttled cgroups
  sched/cpufreq: Use %pe format for PTR_ERR() printing
  sched/rt: Skip currently executing CPU in rto_next_cpu()
  sched/clock: Avoid false sharing for sched_clock_irqtime
  selftests/sched_ext: Add test for DL server total_bw consistency
  selftests/sched_ext: Add test for sched_ext dl_server
  sched/debug: Fix dl_server (re)start conditions
  sched/debug: Add support to change sched_ext server params
  sched_ext: Add a DL server for sched_ext tasks
  sched/debug: Stop and start server based on if it was active
  sched/debug: Fix updating of ppos on server write ops
  sched/deadline: Clear the defer params
  entry: Inline syscall_exit_work() and syscall_trace_enter()
  entry: Add arch_ptrace_report_syscall_entry/exit()
  entry: Rework syscall_exit_to_user_mode_work() for architecture reuse
  entry: Remove unused syscall argument from syscall_trace_enter()
  sched: remove task_struct->faults_disabled_mapping
  sched: Update rq->avg_idle when a task is moved to an idle CPU
  selftests/rseq: Add rseq slice histogram script
  hrtimer: Fix trace oddity
  ...
2026-02-10 12:50:10 -08:00
Linus Torvalds
0923fd0419 Merge tag 'locking-core-2026-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "Lock debugging:

   - Implement compiler-driven static analysis locking context checking,
     using the upcoming Clang 22 compiler's context analysis features
     (Marco Elver)

     We removed Sparse context analysis support, because prior to
     removal even a defconfig kernel produced 1,700+ context tracking
     Sparse warnings, the overwhelming majority of which are false
     positives. On an allmodconfig kernel the number of false positive
     context tracking Sparse warnings grows to over 5,200... On the plus
     side of the balance actual locking bugs found by Sparse context
     analysis is also rather ... sparse: I found only 3 such commits in
     the last 3 years. So the rate of false positives and the
     maintenance overhead is rather high and there appears to be no
     active policy in place to achieve a zero-warnings baseline to move
     the annotations & fixers to developers who introduce new code.

     Clang context analysis is more complete and more aggressive in
     trying to find bugs, at least in principle. Plus it has a different
     model to enabling it: it's enabled subsystem by subsystem, which
     results in zero warnings on all relevant kernel builds (as far as
     our testing managed to cover it). Which allowed us to enable it by
     default, similar to other compiler warnings, with the expectation
     that there are no warnings going forward. This enforces a
     zero-warnings baseline on clang-22+ builds (Which are still limited
     in distribution, admittedly)

     Hopefully the Clang approach can lead to a more maintainable
     zero-warnings status quo and policy, with more and more subsystems
     and drivers enabling the feature. Context tracking can be enabled
     for all kernel code via WARN_CONTEXT_ANALYSIS_ALL=y (default
     disabled), but this will generate a lot of false positives.

     ( Having said that, Sparse support could still be added back,
       if anyone is interested - the removal patch is still
       relatively straightforward to revert at this stage. )

  Rust integration updates: (Alice Ryhl, Fujita Tomonori, Boqun Feng)

    - Add support for Atomic<i8/i16/bool> and replace most Rust native
      AtomicBool usages with Atomic<bool>

    - Clean up LockClassKey and improve its documentation

    - Add missing Send and Sync trait implementation for SetOnce

    - Make ARef Unpin as it is supposed to be

    - Add __rust_helper to a few Rust helpers as a preparation for
      helper LTO

    - Inline various lock related functions to avoid additional function
      calls

  WW mutexes:

    - Extend ww_mutex tests and other test-ww_mutex updates (John
      Stultz)

  Misc fixes and cleanups:

    - rcu: Mark lockdep_assert_rcu_helper() __always_inline (Arnd
      Bergmann)

    - locking/local_lock: Include more missing headers (Peter Zijlstra)

    - seqlock: fix scoped_seqlock_read kernel-doc (Randy Dunlap)

    - rust: sync: Replace `kernel::c_str!` with C-Strings (Tamir
      Duberstein)"

* tag 'locking-core-2026-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (90 commits)
  locking/rwlock: Fix write_trylock_irqsave() with CONFIG_INLINE_WRITE_TRYLOCK
  rcu: Mark lockdep_assert_rcu_helper() __always_inline
  compiler-context-analysis: Remove __assume_ctx_lock from initializers
  tomoyo: Use scoped init guard
  crypto: Use scoped init guard
  kcov: Use scoped init guard
  compiler-context-analysis: Introduce scoped init guards
  cleanup: Make __DEFINE_LOCK_GUARD handle commas in initializers
  seqlock: fix scoped_seqlock_read kernel-doc
  tools: Update context analysis macros in compiler_types.h
  rust: sync: Replace `kernel::c_str!` with C-Strings
  rust: sync: Inline various lock related methods
  rust: helpers: Move #define __rust_helper out of atomic.c
  rust: wait: Add __rust_helper to helpers
  rust: time: Add __rust_helper to helpers
  rust: task: Add __rust_helper to helpers
  rust: sync: Add __rust_helper to helpers
  rust: refcount: Add __rust_helper to helpers
  rust: rcu: Add __rust_helper to helpers
  rust: processor: Add __rust_helper to helpers
  ...
2026-02-10 12:28:44 -08:00
Linus Torvalds
4d84667627 Merge tag 'perf-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull performance event updates from Ingo Molnar:
 "x86 PMU driver updates:

   - Add support for the core PMU for Intel Diamond Rapids (DMR) CPUs
     (Dapeng Mi)

     Compared to previous iterations of the Intel PMU code, there's been
     a lot of changes, which center around three main areas:

      - Introduce the OFF-MODULE RESPONSE (OMR) facility to replace the
        Off-Core Response (OCR) facility

      - New PEBS data source encoding layout

      - Support the new "RDPMC user disable" feature

   - Likewise, a large series adds uncore PMU support for Intel Diamond
     Rapids (DMR) CPUs (Zide Chen)

     This centers around these four main areas:

      - DMR may have two Integrated I/O and Memory Hub (IMH) dies,
        separate from the compute tile (CBB) dies. Each CBB and each IMH
        die has its own discovery domain.

      - Unlike prior CPUs that retrieve the global discovery table
        portal exclusively via PCI or MSR, DMR uses PCI for IMH PMON
        discovery and MSR for CBB PMON discovery.

      - DMR introduces several new PMON types: SCA, HAMVF, D2D_ULA, UBR,
        PCIE4, CRS, CPC, ITC, OTC, CMS, and PCIE6.

      - IIO free-running counters in DMR are MMIO-based, unlike SPR.

   - Also add support for Add missing PMON units for Intel Panther Lake,
     and support Nova Lake (NVL), which largely maps to Panther Lake.
     (Zide Chen)

   - KVM integration: Add support for mediated vPMUs (by Kan Liang and
     Sean Christopherson, with fixes and cleanups by Peter Zijlstra,
     Sandipan Das and Mingwei Zhang)

   - Add Intel cstate driver to support for Wildcat Lake (WCL) CPUs,
     which are a low-power variant of Panther Lake (Zide Chen)

   - Add core, cstate and MSR PMU support for the Airmont NP Intel CPU
     (aka MaxLinear Lightning Mountain), which maps to the existing
     Airmont code (Martin Schiller)

  Performance enhancements:

   - Speed up kexec shutdown by avoiding unnecessary cross CPU calls
     (Jan H. Schönherr)

   - Fix slow perf_event_task_exit() with LBR callstacks (Namhyung Kim)

  User-space stack unwinding support:

   - Various cleanups and refactorings in preparation to generalize the
     unwinding code for other architectures (Jens Remus)

  Uprobes updates:

   - Transition from kmap_atomic to kmap_local_page (Keke Ming)

   - Fix incorrect lockdep condition in filter_chain() (Breno Leitao)

   - Fix XOL allocation failure for 32-bit tasks (Oleg Nesterov)

  Misc fixes and cleanups:

   - s390: Remove kvm_types.h from Kbuild (Randy Dunlap)

   - x86/intel/uncore: Convert comma to semicolon (Chen Ni)

   - x86/uncore: Clean up const mismatch (Greg Kroah-Hartman)

   - x86/ibs: Fix typo in dc_l2tlb_miss comment (Xiang-Bin Shi)"

* tag 'perf-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  s390: remove kvm_types.h from Kbuild
  uprobes: Fix incorrect lockdep condition in filter_chain()
  x86/ibs: Fix typo in dc_l2tlb_miss comment
  x86/uprobes: Fix XOL allocation failure for 32-bit tasks
  perf/x86/intel/uncore: Convert comma to semicolon
  perf/x86/intel: Add support for rdpmc user disable feature
  perf/x86: Use macros to replace magic numbers in attr_rdpmc
  perf/x86/intel: Add core PMU support for Novalake
  perf/x86/intel: Add support for PEBS memory auxiliary info field in NVL
  perf/x86/intel: Add core PMU support for DMR
  perf/x86/intel: Add support for PEBS memory auxiliary info field in DMR
  perf/x86/intel: Support the 4 new OMR MSRs introduced in DMR and NVL
  perf/core: Fix slow perf_event_task_exit() with LBR callstacks
  perf/core: Speed up kexec shutdown by avoiding unnecessary cross CPU calls
  uprobes: use kmap_local_page() for temporary page mappings
  arm/uprobes: use kmap_local_page() in arch_uprobe_copy_ixol()
  mips/uprobes: use kmap_local_page() in arch_uprobe_copy_ixol()
  arm64/uprobes: use kmap_local_page() in arch_uprobe_copy_ixol()
  riscv/uprobes: use kmap_local_page() in arch_uprobe_copy_ixol()
  perf/x86/intel/uncore: Add Nova Lake support
  ...
2026-02-10 12:00:46 -08:00
Linus Torvalds
f17b474e36 Merge tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:

 - Support associating BPF program with struct_ops (Amery Hung)

 - Switch BPF local storage to rqspinlock and remove recursion detection
   counters which were causing false positives (Amery Hung)

 - Fix live registers marking for indirect jumps (Anton Protopopov)

 - Introduce execution context detection BPF helpers (Changwoo Min)

 - Improve verifier precision for 32bit sign extension pattern
   (Cupertino Miranda)

 - Optimize BTF type lookup by sorting vmlinux BTF and doing binary
   search (Donglin Peng)

 - Allow states pruning for misc/invalid slots in iterator loops (Eduard
   Zingerman)

 - In preparation for ASAN support in BPF arenas teach libbpf to move
   global BPF variables to the end of the region and enable arena kfuncs
   while holding locks (Emil Tsalapatis)

 - Introduce support for implicit arguments in kfuncs and migrate a
   number of them to new API. This is a prerequisite for cgroup
   sub-schedulers in sched-ext (Ihor Solodrai)

 - Fix incorrect copied_seq calculation in sockmap (Jiayuan Chen)

 - Fix ORC stack unwind from kprobe_multi (Jiri Olsa)

 - Speed up fentry attach by using single ftrace direct ops in BPF
   trampolines (Jiri Olsa)

 - Require frozen map for calculating map hash (KP Singh)

 - Fix lock entry creation in TAS fallback in rqspinlock (Kumar
   Kartikeya Dwivedi)

 - Allow user space to select cpu in lookup/update operations on per-cpu
   array and hash maps (Leon Hwang)

 - Make kfuncs return trusted pointers by default (Matt Bobrowski)

 - Introduce "fsession" support where single BPF program is executed
   upon entry and exit from traced kernel function (Menglong Dong)

 - Allow bpf_timer and bpf_wq use in all programs types (Mykyta
   Yatsenko, Andrii Nakryiko, Kumar Kartikeya Dwivedi, Alexei
   Starovoitov)

 - Make KF_TRUSTED_ARGS the default for all kfuncs and clean up their
   definition across the tree (Puranjay Mohan)

 - Allow BPF arena calls from non-sleepable context (Puranjay Mohan)

 - Improve register id comparison logic in the verifier and extend
   linked registers with negative offsets (Puranjay Mohan)

 - In preparation for BPF-OOM introduce kfuncs to access memcg events
   (Roman Gushchin)

 - Use CFI compatible destructor kfunc type (Sami Tolvanen)

 - Add bitwise tracking for BPF_END in the verifier (Tianci Cao)

 - Add range tracking for BPF_DIV and BPF_MOD in the verifier (Yazhou
   Tang)

 - Make BPF selftests work with 64k page size (Yonghong Song)

* tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (268 commits)
  selftests/bpf: Fix outdated test on storage->smap
  selftests/bpf: Choose another percpu variable in bpf for btf_dump test
  selftests/bpf: Remove test_task_storage_map_stress_lookup
  selftests/bpf: Update task_local_storage/task_storage_nodeadlock test
  selftests/bpf: Update task_local_storage/recursion test
  selftests/bpf: Update sk_storage_omem_uncharge test
  bpf: Switch to bpf_selem_unlink_nofail in bpf_local_storage_{map_free, destroy}
  bpf: Support lockless unlink when freeing map or local storage
  bpf: Prepare for bpf_selem_unlink_nofail()
  bpf: Remove unused percpu counter from bpf_local_storage_map_free
  bpf: Remove cgroup local storage percpu counter
  bpf: Remove task local storage percpu counter
  bpf: Change local_storage->lock and b->lock to rqspinlock
  bpf: Convert bpf_selem_unlink to failable
  bpf: Convert bpf_selem_link_map to failable
  bpf: Convert bpf_selem_unlink_map to failable
  bpf: Select bpf_local_storage_map_bucket based on bpf_local_storage
  selftests/xsk: fix number of Tx frags in invalid packet
  selftests/xsk: properly handle batch ending in the middle of a packet
  bpf: Prevent reentrance into call_rcu_tasks_trace()
  ...
2026-02-10 11:26:21 -08:00
Linus Torvalds
a7423e6ea2 Merge tag 'modules-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux
Pull module updates from Sami Tolvanen:
 "Module signing:

   - Remove SHA-1 support for signing modules.

     SHA-1 is no longer considered secure for signatures due to
     vulnerabilities that can lead to hash collisions. None of the major
     distributions use SHA-1 anymore, and the kernel has defaulted to
     SHA-512 since v6.11.

     Note that loading SHA-1 signed modules is still supported.

   - Update scripts/sign-file to use only the OpenSSL CMS API for
     signing.

     As SHA-1 support is gone, we can drop the legacy PKCS#7 API which
     was limited to SHA-1. This also cleans up support for legacy
     OpenSSL versions.

  Cleanups and fixes:

   - Use system_dfl_wq instead of the per-cpu system_wq following the
     ongoing workqueue API refactoring.

   - Avoid open-coded kvrealloc() in module decompression logic by using
     the standard helper.

   - Improve section annotations by replacing the custom __modinit with
     __init_or_module and removing several unused __INIT*_OR_MODULE
     macros.

   - Fix kernel-doc warnings in include/linux/moduleparam.h.

   - Ensure set_module_sig_enforced is only declared when module signing
     is enabled.

   - Fix gendwarfksyms build failures on 32-bit hosts.

  MAINTAINERS:

   - Update the module subsystem entry to reflect the maintainer
     rotation and update the git repository link"

* tag 'modules-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux:
  modules: moduleparam.h: fix kernel-doc comments
  module: Only declare set_module_sig_enforced when CONFIG_MODULE_SIG=y
  module/decompress: Avoid open-coded kvrealloc()
  gendwarfksyms: Fix build on 32-bit hosts
  sign-file: Use only the OpenSSL CMS API for signing
  module: Remove SHA-1 support for module signing
  module: replace use of system_wq with system_dfl_wq
  params: Replace __modinit with __init_or_module
  module: Remove unused __INIT*_OR_MODULE macros
  MAINTAINERS: Update module subsystem maintainers and repository
2026-02-10 09:49:18 -08:00
Linus Torvalds
08df88fa14 Merge tag 'v7.0-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "API:
   - Fix race condition in hwrng core by using RCU

  Algorithms:
   - Allow authenc(sha224,rfc3686) in fips mode
   - Add test vectors for authenc(hmac(sha384),cbc(aes))
   - Add test vectors for authenc(hmac(sha224),cbc(aes))
   - Add test vectors for authenc(hmac(md5),cbc(des3_ede))
   - Add lz4 support in hisi_zip
   - Only allow clear key use during self-test in s390/{phmac,paes}

  Drivers:
   - Set rng quality to 900 in airoha
   - Add gcm(aes) support for AMD/Xilinx Versal device
   - Allow tfms to share device in hisilicon/trng"

* tag 'v7.0-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (100 commits)
  crypto: img-hash - Use unregister_ahashes in img_{un}register_algs
  crypto: testmgr - Add test vectors for authenc(hmac(md5),cbc(des3_ede))
  crypto: cesa - Simplify return statement in mv_cesa_dequeue_req_locked
  crypto: testmgr - Add test vectors for authenc(hmac(sha224),cbc(aes))
  crypto: testmgr - Add test vectors for authenc(hmac(sha384),cbc(aes))
  hwrng: core - use RCU and work_struct to fix race condition
  crypto: starfive - Fix memory leak in starfive_aes_aead_do_one_req()
  crypto: xilinx - Fix inconsistant indentation
  crypto: rng - Use unregister_rngs in register_rngs
  crypto: atmel - Use unregister_{aeads,ahashes,skciphers}
  hwrng: optee - simplify OP-TEE context match
  crypto: ccp - Add sysfs attribute for boot integrity
  dt-bindings: crypto: atmel,at91sam9g46-sha: add microchip,lan9691-sha
  dt-bindings: crypto: atmel,at91sam9g46-aes: add microchip,lan9691-aes
  dt-bindings: crypto: qcom,inline-crypto-engine: document the Milos ICE
  crypto: caam - fix netdev memory leak in dpaa2_caam_probe
  crypto: hisilicon/qm - increase wait time for mailbox
  crypto: hisilicon/qm - obtain the mailbox configuration at one time
  crypto: hisilicon/qm - remove unnecessary code in qm_mb_write()
  crypto: hisilicon/qm - move the barrier before writing to the mailbox register
  ...
2026-02-10 08:36:42 -08:00
Oleg Nesterov
1cf2e88e06 Revert "pid: make __task_pid_nr_ns(ns => NULL) safe for zombie callers"
This reverts commit abdfd4948e.

The changelog in this commit explains why it is not easy to avoid ns == NULL
when the caller is exiting, but pid_vnr() is equally unsafe in this case.

However, commit 006568ab4c ("pid: Add a judgment for ns null in pid_nr_ns")
already added the ns != NULL check in pid_nr_ns(), so we can remove the same
check from __task_pid_nr_ns().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://patch.msgid.link/20251015123613.GA9456@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-10 11:39:30 +01:00
Mateusz Guzik
87caaeef79 pidfs: implement ino allocation without the pidmap lock
This paves the way for scalable PID allocation later.

The 32 bit variant merely takes a spinlock for simplicity, the 64 bit
variant uses a scalable scheme.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20260120184539.1480930-1-mjguzik@gmail.com
Co-developed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-10 11:39:30 +01:00
Christian Brauner
8021824904 pidfs: convert rb-tree to rhashtable
Mateusz reported performance penalties [1] during task creation because
pidfs uses pidmap_lock to add elements into the rbtree. Switch to an
rhashtable to have separate fine-grained locking and to decouple from
pidmap_lock moving all heavy manipulations outside of it.

Convert the pidfs inode-to-pid mapping from an rb-tree with seqcount
protection to an rhashtable. This removes the global pidmap_lock
contention from pidfs_ino_get_pid() lookups and allows the hashtable
insert to happen outside the pidmap_lock.

pidfs_add_pid() is split. pidfs_prepare_pid() allocates inode number and
initializes pid fields and is called inside pidmap_lock. pidfs_add_pid()
inserts pid into rhashtable and is called outside pidmap_lock. Insertion
into the rhashtable can fail and memory allocation may happen so we need
to drop the spinlock.

To guard against accidently opening an already reaped task
pidfs_ino_get_pid() uses additional checks beyond pid_vnr(). If
pid->attr is PIDFS_PID_DEAD or NULL the pid either never had a pidfd or
it already went through pidfs_exit() aka the process as already reaped.
If pid->attr is valid check PIDFS_ATTR_BIT_EXIT to figure out whether
the task has exited.

This slightly changes visibility semantics: pidfd creation is denied
after pidfs_exit() runs, which is just before the pid number is removed
from the via free_pid(). That should not be an issue though.

Link: https://lore.kernel.org/20251206131955.780557-1-mjguzik@gmail.com [1]
Link: https://patch.msgid.link/20260120-work-pidfs-rhashtable-v2-1-d593c4d0f576@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-10 11:39:30 +01:00
Colin Lord
f743435f98 tracing: Fix false sharing in hwlat get_sample()
The get_sample() function in the hwlat tracer assumes the caller holds
hwlat_data.lock, but this is not actually happening. The result is
unprotected data access to hwlat_data, and in per-cpu mode can result in
false sharing which may show up as false positive latency events.

The specific case of false sharing observed was primarily between
hwlat_data.sample_width and hwlat_data.count. These are separated by
just 8B and are therefore likely to share a cache line. When one thread
modifies count, the cache line is in a modified state so when other
threads read sample_width in the main latency detection loop, they fetch
the modified cache line. On some systems, the fetch itself may be slow
enough to count as a latency event, which could set up a self
reinforcing cycle of latency events as each event increments count which
then causes more latency events, continuing the cycle.

The other result of the unprotected data access is that hwlat_data.count
can end up with duplicate or missed values, which was observed on some
systems in testing.

Convert hwlat_data.count to atomic64_t so it can be safely modified
without locking, and prevent false sharing by pulling sample_width into
a local variable.

One system this was tested on was a dual socket server with 32 CPUs on
each numa node. With settings of 1us threshold, 1000us width, and
2000us window, this change reduced the number of latency events from
500 per second down to approximately 1 event per minute. Some machines
tested did not exhibit measurable latency from the false sharing.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20260210074810.6328-1-clord@mykolab.com
Signed-off-by: Colin Lord <clord@mykolab.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-10 03:36:39 -05:00
Linus Torvalds
d16738a4e7 Merge tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks
Pull kthread updates from Frederic Weisbecker:
 "The kthread code provides an infrastructure which manages the
  preferred affinity of unbound kthreads (node or custom cpumask)
  against housekeeping (CPU isolation) constraints and CPU hotplug
  events.

  One crucial missing piece is the handling of cpuset: when an isolated
  partition is created, deleted, or its CPUs updated, all the unbound
  kthreads in the top cpuset become indifferently affine to _all_ the
  non-isolated CPUs, possibly breaking their preferred affinity along
  the way.

  Solve this with performing the kthreads affinity update from cpuset to
  the kthreads consolidated relevant code instead so that preferred
  affinities are honoured and applied against the updated cpuset
  isolated partitions.

  The dispatch of the new isolated cpumasks to timers, workqueues and
  kthreads is performed by housekeeping, as per the nice Tejun's
  suggestion.

  As a welcome side effect, HK_TYPE_DOMAIN then integrates both the set
  from boot defined domain isolation (through isolcpus=) and cpuset
  isolated partitions. Housekeeping cpumasks are now modifiable with a
  specific RCU based synchronization. A big step toward making
  nohz_full= also mutable through cpuset in the future"

* tag 'kthread-for-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks: (33 commits)
  doc: Add housekeeping documentation
  kthread: Document kthread_affine_preferred()
  kthread: Comment on the purpose and placement of kthread_affine_node() call
  kthread: Honour kthreads preferred affinity after cpuset changes
  sched/arm64: Move fallback task cpumask to HK_TYPE_DOMAIN
  sched: Switch the fallback task allowed cpumask to HK_TYPE_DOMAIN
  kthread: Rely on HK_TYPE_DOMAIN for preferred affinity management
  kthread: Include kthreadd to the managed affinity list
  kthread: Include unbound kthreads in the managed affinity list
  kthread: Refine naming of affinity related fields
  PCI: Remove superfluous HK_TYPE_WQ check
  sched/isolation: Remove HK_TYPE_TICK test from cpu_is_isolated()
  cpuset: Remove cpuset_cpu_is_isolated()
  timers/migration: Remove superfluous cpuset isolation test
  cpuset: Propagate cpuset isolation update to timers through housekeeping
  cpuset: Propagate cpuset isolation update to workqueue through housekeeping
  PCI: Flush PCI probe workqueue on cpuset isolated partition change
  sched/isolation: Flush vmstat workqueues on cpuset isolated partition change
  sched/isolation: Flush memcg workqueues on cpuset isolated partition change
  cpuset: Update HK_TYPE_DOMAIN cpumask from cpuset
  ...
2026-02-09 19:57:30 -08:00
Linus Torvalds
9b1b3dcd28 Merge tag 'pm-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
 "By the number of commits, cpufreq is the leading party (again) and the
  most visible change there is the removal of the omap-cpufreq driver
  that has not been used for a long time (good riddance). There are also
  quite a few changes in the cppc_cpufreq driver, mostly related to
  fixing its frequency invariance engine in the case when the CPPC
  registers used by it are not in PCC. In addition to that, support for
  AM62L3 is added to the ti-cpufreq driver and the cpufreq-dt-platdev
  list is updated for some platforms. The remaining cpufreq changes are
  assorted fixes and cleanups.

  Next up is cpuidle and the changes there are dominated by intel_idle
  driver updates, mostly related to the new command line facility
  allowing users to adjust the list of C-states used by the driver.
  There are also a few updates of cpuidle governors, including two menu
  governor fixes and some refinements of the teo governor, and a
  MAINTAINERS update adding Christian Loehle as a cpuidle reviewer.
  [Thanks for stepping up Christian!]

  The most significant update related to system suspend and hibernation
  is the one to stop freezing the PM runtime workqueue during system PM
  transitions which allows some deadlocks to be avoided. There is also a
  fix for possible concurrent bit field updates in the core device
  suspend code and a few other minor fixes.

  Apart from the above, several drivers are updated to discard the
  return value of pm_runtime_put() which is going to be converted to a
  void function as soon as everybody stops using its return value, PL4
  support for Ice Lake is added to the Intel RAPL power capping driver,
  and there are assorted cleanups, documentation fixes, and some
  cpupower utility improvements.

  Specifics:

   - Remove the unused omap-cpufreq driver (Andreas Kemnade)

   - Optimize error handling code in cpufreq_boost_trigger_state() and
     make cpufreq_boost_trigger_state() return -EOPNOTSUPP if no policy
     supports boost (Lifeng Zheng)

   - Update cpufreq-dt-platdev list for tegra, qcom, TI (Aaron Kling,
     Dhruva Gole, and Konrad Dybcio)

   - Minor improvements to the cpufreq and cpumask rust implementation
     (Alexandre Courbot, Alice Ryhl, Tamir Duberstein, and Yilin Chen)

   - Add support for AM62L3 SoC to the ti-cpufreq driver (Dhruva Gole)

   - Update arch_freq_scale in the CPPC cpufreq driver's frequency
     invariance engine (FIE) in scheduler ticks if the related CPPC
     registers are not in PCC (Jie Zhan)

   - Assorted minor cleanups and improvements in ARM cpufreq drivers
     (Juan Martinez, Felix Gu, Luca Weiss, and Sergey Shtylyov)

   - Add generic helpers for sysfs show/store to cppc_cpufreq (Sumit
     Gupta)

   - Make the scaling_setspeed cpufreq sysfs attribute return the actual
     requested frequency to avoid confusion (Pengjie Zhang)

   - Simplify the idle CPU time granularity test in the ondemand cpufreq
     governor (Frederic Weisbecker)

   - Enable asym capacity in intel_pstate only when CPU SMT is not
     possible (Yaxiong Tian)

   - Update the description of rate_limit_us default value in cpufreq
     documentation (Yaxiong Tian)

   - Add a command line option to adjust the C-states table in the
     intel_idle driver, remove the 'preferred_cstates' module parameter
     from it, add C-states validation to it and clean it up (Artem
     Bityutskiy)

   - Make the menu cpuidle governor always check the time till the
     closest timer event when the scheduler tick has been stopped to
     prevent it from mistakenly selecting the deepest available idle
     state (Rafael Wysocki)

   - Update the teo cpuidle governor to avoid making suboptimal
     decisions in certain corner cases and generally improve idle state
     selection accuracy (Rafael Wysocki)

   - Remove an unlikely() annotation on the early-return condition in
     menu_select() that leads to branch misprediction 100% of the time
     on systems with only 1 idle state enabled, like ARM64 servers
     (Breno Leitao)

   - Add Christian Loehle to MAINTAINERS as a cpuidle reviewer
     (Christian Loehle)

   - Stop flagging the PM runtime workqueue as freezable to avoid system
     suspend and resume deadlocks in subsystems that assume asynchronous
     runtime PM to work during system-wide PM transitions (Rafael
     Wysocki)

   - Drop redundant NULL pointer checks before acomp_request_free() from
     the hibernation code handling image saving (Rafael Wysocki)

   - Update wakeup_sources_walk_start() to handle empty lists of wakeup
     sources as appropriate (Samuel Wu)

   - Make dev_pm_clear_wake_irq() check the power.wakeirq value under
     power.lock to avoid race conditions (Gui-Dong Han)

   - Avoid bit field races related to power.work_in_progress in the core
     device suspend code (Xuewen Yan)

   - Make several drivers discard pm_runtime_put() return value in
     preparation for converting that function to a void one (Rafael
     Wysocki)

   - Add PL4 support for Ice Lake to the Intel RAPL power capping driver
     (Daniel Tang)

   - Replace sprintf() with sysfs_emit() in power capping sysfs show
     functions (Sumeet Pawnikar)

   - Make dev_pm_opp_get_level() return value match the documentation
     after a previous update of the latter (Aleks Todorov)

   - Use scoped for each OF child loop in the OPP code (Krzysztof
     Kozlowski)

   - Fix a bug in an example code snippet and correct typos in the
     energy model management documentation (Patrick Little)

   - Fix miscellaneous problems in cpupower (Kaushlendra Kumar):
      * idle_monitor: Fix incorrect value logged after stop
      * Fix inverted APERF capability check
      * Use strcspn() to strip trailing newline
      * Reset errno before strtoull()
      * Show C0 in idle-info dump

   - Improve cpupower installation procedure by making the systemd step
     optional and allowing users to disable the installation of
     systemd's unit file (João Marcos Costa)"

* tag 'pm-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (65 commits)
  PM: sleep: core: Avoid bit field races related to work_in_progress
  PM: sleep: wakeirq: harden dev_pm_clear_wake_irq() against races
  cpufreq: Documentation: Update description of rate_limit_us default value
  cpufreq: intel_pstate: Enable asym capacity only when CPU SMT is not possible
  PM: wakeup: Handle empty list in wakeup_sources_walk_start()
  PM: EM: Documentation: Fix bug in example code snippet
  Documentation: Fix typos in energy model documentation
  cpuidle: governors: teo: Refine intercepts-based idle state lookup
  cpuidle: governors: teo: Adjust the classification of wakeup events
  cpufreq: ondemand: Simplify idle cputime granularity test
  cpufreq: userspace: make scaling_setspeed return the actual requested frequency
  PM: hibernate: Drop NULL pointer checks before acomp_request_free()
  cpufreq: CPPC: Add generic helpers for sysfs show/store
  cpufreq: scmi: Fix device_node reference leak in scmi_cpu_domain_id()
  cpufreq: ti-cpufreq: add support for AM62L3 SoC
  cpufreq: dt-platdev: Add ti,am62l3 to blocklist
  cpufreq/amd-pstate: Add comment explaining nominal_perf usage for performance policy
  cpufreq: scmi: correct SCMI explanation
  cpufreq: dt-platdev: Block the driver from probing on more QC platforms
  rust: cpumask: rename methods of Cpumask for clarity and consistency
  ...
2026-02-09 19:00:42 -08:00
Linus Torvalds
d84e173311 Merge tag 'acpi-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
 "This one is significantly larger than previous ACPI support pull
  requests because several significant updates have coincided in it.

  First, there is a routine ACPICA code update, to upstream version
  20251212, but this time it covers new ACPI 6.6 material that has not
  been covered yet. Among other things, it includes definitions of a few
  new ACPI tables and updates of some others, like the GICv5 MADT
  structures and ARM IORT IWB node definitions that are used for adding
  GICv5 ACPI probing on ARM (that technically is IRQ subsystem material,
  but it depends on the ACPICA changes, so it is included here). The
  latter alone adds a few hundred lines of new code.

  Second, there is an update of ACPI _OSC handling including a fix that
  prevents failures from occurring in some corner cases due to careless
  handling of _OSC error bits.

  On top of that, the "system resource" ACPI device objects with the
  PNP0C01 and PNP0C02 are now going to be handled by the ACPI core
  device enumeration code instead of handing them over to the legacy PNP
  system driver which causes device enumeration issues to occur. Some of
  those issues have been worked around in device drivers and elsewhere
  and those workarounds should not be necessary any more, so they are
  going away.

  Moreover, the time has come to convert all "core ACPI" device drivers
  that were still using struct acpi_driver objects for device binding
  into proper platform drivers that use struct platform_driver for this
  purpose. These updates are accompanied by some requisite core ACPI
  device enumeration code changes.

  Next, there are ACPI APEI updates, including changes to avoid excess
  overhead in the NMI handler and in SEA on the ARM side, changes to
  unify ACPI-based HW error tracing and logging, and changes to prevent
  APEI code from reaching out of its allocated memory.

  There are also some ACPI power management updates, mostly related to
  the ACPI cpuidle support in the processor driver, suspend-to-idle
  handling on systems with ACPI support and to ACPI PM of devices.

  In addition to the above, bugs are fixed and the code is cleaned up in
  assorted places all over.

  Specifics:

   - Update the ACPICA code in the kernel to upstream version 20251212
     which includes the following changes:
      * Add support for new ACPI table DTPR (Michal Camacho Romero)
      * Release objects with acpi_ut_delete_object_desc() (Zilin Guan)
      * Add UUIDs for Microsoft fan extensions and UUIDs associated with
        TPM 2.0 devices (Armin Wolf)
      * Fix NULL pointer dereference in acpi_ev_address_space_dispatch()
        (Alexey Simakov)
      * Add KEYP ACPI table definition (Dave Jiang)
      * Add support for the Microsoft display mux _OSI string (Armin
        Wolf)
      * Add definitions for the IOVT ACPI table (Xianglai Li)
      * Abort AML bytecode execution on AML_FATAL_OP (Armin Wolf)
      * Include all fields in subtable type1 for PPTT (Ben Horgan)
      * Add GICv5 MADT structures and Arm IORT IWB node definitions
        (Jose Marinho)
      * Update Parameter Block structure for RAS2 and add a new flag in
        Memory Affinity Structure for SRAT (Pawel Chmielewski)
      * Add _VDM (Voltage Domain) object (Pawel Chmielewski)

   - Add support for GICv5 ACPI probing on ARM which is based on the
     GICv5 MADT structures and ARM IORT IWB node definitions recently
     added to ACPICA (Lorenzo Pieralisi)

   - Rework ACPI PM notification setup for PCI root buses and modify the
     ACPI PM setup for devices to register wakeup source objects under
     physical (that is, PCI, platform, etc.) devices instead of doing
     that under their ACPI companions (Rafael Wysocki)

   - Adjust debug messages regarding postponed ACPI PM printed during
     system resume to be more accurate (Rafael Wysocki)

   - Remove dead code from lps0_device_attach() (Gergo Koteles)

   - Start to invoke Microsoft Function 9 (Turn On Display) of the Low-
     Power S0 Idle (LPS0) _DSM in the suspend-to-idle resume flow on
     systems with ACPI LPS0 support to address a functional issue on
     Lenovo Yoga Slim 7i Aura (15ILL9), where system fans and keyboard
     backlights fail to resume after suspend (Jakob Riemenschneider)

   - Add sysfs attribute cid for exposing _CID lists under ACPI device
     objects (Rafael Wysocki)

   - Replace sprintf() with sysfs_emit() in all of the core ACPI sysfs
     interface code (Sumeet Pawnikar)

   - Use acpi_get_local_u64_address() in the code implementing ACPI
     support for PCI to evaluate _ADR instead of evaluating that object
     directly (Andy Shevchenko)

   - Add JWIPC JVC9100 to irq1_level_low_skip_override[] to unbreak
     serial IRQs on that system (Ai Chao)

   - Fix handling of _OSC errors in acpi_run_osc() to avoid failures on
     systems where _OSC error bits are set even though the _OSC return
     buffer contains acknowledged feature bits (Rafael Wysocki)

   - Clean up and rearrange \_SB._OSC handling for general platform
     features and USB4 features to avoid code duplication and
     unnecessary memory management overhead (Rafael Wysocki)

   - Make the ACPI core device enumeration code handle PNP0C01 and
     PNP0C02 ("system resource") device objects directly instead of
     letting the legacy PNP system driver handle them to avoid device
     enumeration issues on systems where PNP0C02 is present in the _CID
     list under ACPI device objects with a _HID matching a proper device
     driver in Linux (Rafael Wysocki)

   - Drop workarounds for the known device enumeration issues related to
     _CID lists containing PNP0C02 (Rafael Wysocki)

   - Drop outdated comment regarding removed function in the ACPI-based
     device enumeration code (Julia Lawall)

   - Make PRP0001 device matching work as expected for ACPI device
     objects using it as a _HID for board development and similar
     purposes (Kartik Rajput)

   - Use async schedule function in acpi_scan_clear_dep_fn() to avoid
     races with user space initialization on some systems (Yicong Yang)

   - Add a piece of documentation explaining why binding drivers
     directly to ACPI device objects is not a good idea in general and
     why it is desirable to convert drivers doing so into proper
     platform drivers that use struct platform_driver for device binding
     (Rafael Wysocki)

   - Convert multiple "core ACPI" drivers, including the NFIT ACPI
     device driver, the generic ACPI button drivers, the generic ACPI
     thermal zone driver, the ACPI hardware event device (HED) driver,
     the ACPI EC driver, the ACPI SMBUS HC driver, the ACPI Smart
     Battery Subsystem (SBS) driver, and the ACPI backlight (video)
     driver to proper platform drivers that use struct platform_driver
     for device binding (Rafael Wysocki)

   - Use acpi_get_local_u64_address() in the ACPI backlight (video)
     driver to evaluate _ADR instead of evaluating that object directly
     (Andy Shevchenko)

   - Convert the generic ACPI battery driver to a proper platform driver
     using struct platform_driver for device binding (Rafael Wysocki)

   - Fix incorrect charging status when current is zero in the generic
     ACPI battery driver (Ata İlhan Köktürk)

   - Use LIST_HEAD() for initializing a stack-allocated list in the
     generic ACPI watchdog device driver (Can Peng)

   - Rework the ACPI idle driver initialization to register it directly
     from the common initialization code instead of doing that from a
     CPU hotplug "online" callback and clean it up (Huisong Li, Rafael
     Wysocki)

   - Fix a possible NULL pointer dereference in
     acpi_processor_errata_piix4() (Tuo Li)

   - Make read-only array non_mmio_desc[] static const (Colin Ian King)

   - Prevent the APEI GHES support code on ARM from accessing memory out
     of bounds or going past the ARM processor CPER record buffer (Mauro
     Carvalho Chehab)

   - Prevent cper_print_fw_err() from dumping the entire memory on
     systems with defective firmware (Mauro Carvalho Chehab)

   - Improve ghes_notify_nmi() status check to avoid unnecessary
     overhead in the NMI handler by carrying out all of the requisite
     preparations and the NMI registration time (Tony Luck)

   - Refactor the GHES driver by extracting common functionality into
     reusable helper functions to reduce code duplication and improve
     the ghes_notify_sea() status check in analogy with the previous
     ghes_notify_nmi() status check improvement (Shuai Xue)

   - Make ELOG and GHES log and trace consistently and support the CPER
     CXL protocol analogously (Fabio De Francesco)

   - Disable KASAN instrumentation in the APEI GHES driver when compile
     testing with clang < 18 (Nathan Chancellor)

   - Let ghes_edac be the preferred driver to load on __ZX__ and _BYO_
     systems by extending the platform detection list in the APEI GHES
     driver (Tony W Wang-oc)

   - Clean up cppc_perf_caps and cppc_perf_ctrls structs and rename EPP
     constants for clarity in the ACPI CPPC library (Sumit Gupta)"

* tag 'acpi-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (117 commits)
  ACPI: battery: fix incorrect charging status when current is zero
  ACPI: scan: Use async schedule function in acpi_scan_clear_dep_fn()
  ACPI: x86: s2idle: Invoke Microsoft _DSM Function 9 (Turn On Display)
  ACPI: APEI: GHES: Add ghes_edac support for __ZX__ and _BYO_ systems
  ACPI: APEI: GHES: Disable KASAN instrumentation when compile testing with clang < 18
  ACPI: sysfs: Replace sprintf() with sysfs_emit()
  ACPI: CPPC: Rename EPP constants for clarity
  ACPI: CPPC: Clean up cppc_perf_caps and cppc_perf_ctrls structs
  ACPI: processor: idle: Rework the handling of acpi_processor_ffh_lpi_probe()
  ACPI: processor: idle: Convert acpi_processor_setup_cpuidle_dev() to void
  ACPI: processor: idle: Convert acpi_processor_setup_cpuidle_states() to void
  irqchip/gic-v5: Add ACPI IWB probing
  irqchip/gic-v5: Add ACPI ITS probing
  irqchip/gic-v5: Add ACPI IRS probing
  irqchip/gic-v5: Split IRS probing into OF and generic portions
  PCI/MSI: Make the pci_msi_map_rid_ctlr_node() interface firmware agnostic
  irqdomain: Add parent field to struct irqchip_fwid
  ACPI: PCI: simplify code with acpi_get_local_u64_address()
  ACPI: video: simplify code with acpi_get_local_u64_address()
  ACPI: PM: Adjust messages regarding postponed ACPI PM
  ...
2026-02-09 18:42:47 -08:00
Linus Torvalds
0c00ed308d Merge tag 'for-7.0/block-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block updates from Jens Axboe:

 - Support for batch request processing for ublk, improving the
   efficiency of the kernel/ublk server communication. This can yield
   nice 7-12% performance improvements

 - Support for integrity data for ublk

 - Various other ublk improvements and additions, including a ton of
   selftests additions and updated

 - Move the handling of blk-crypto software fallback from below the
   block layer to above it. This reduces the complexity of dealing with
   bio splitting

 - Series fixing a number of potential deadlocks in blk-mq related to
   the queue usage counter and writeback throttling and rq-qos debugfs
   handling

 - Add an async_depth queue attribute, to resolve a performance
   regression that's been around for a qhilw related to the scheduler
   depth handling

 - Only use task_work for IOPOLL completions on NVMe, if it is necessary
   to do so. An earlier fix for an issue resulted in all these
   completions being punted to task_work, to guarantee that completions
   were only run for a given io_uring ring when it was local to that
   ring. With the new changes, we can detect if it's necessary to use
   task_work or not, and avoid it if possible.

 - rnbd fixes:
      - Fix refcount underflow in device unmap path
      - Handle PREFLUSH and NOUNMAP flags properly in protocol
      - Fix server-side bi_size for special IOs
      - Zero response buffer before use
      - Fix trace format for flags
      - Add .release to rnbd_dev_ktype

 - MD pull requests via Yu Kuai
      - Fix raid5_run() to return error when log_init() fails
      - Fix IO hang with degraded array with llbitmap
      - Fix percpu_ref not resurrected on suspend timeout in llbitmap
      - Fix GPF in write_page caused by resize race
      - Fix NULL pointer dereference in process_metadata_update
      - Fix hang when stopping arrays with metadata through dm-raid
      - Fix any_working flag handling in raid10_sync_request
      - Refactor sync/recovery code path, improve error handling for
        badblocks, and remove unused recovery_disabled field
      - Consolidate mddev boolean fields into mddev_flags
      - Use mempool to allocate stripe_request_ctx and make sure
        max_sectors is not less than io_opt in raid5
      - Fix return value of mddev_trylock
      - Fix memory leak in raid1_run()
      - Add Li Nan as mdraid reviewer

 - Move phys_vec definitions to the kernel types, mostly in preparation
   for some VFIO and RDMA changes

 - Improve the speed for secure erase for some devices

 - Various little rust updates

 - Various other minor fixes, improvements, and cleanups

* tag 'for-7.0/block-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (162 commits)
  blk-mq: ABI/sysfs-block: fix docs build warnings
  selftests: ublk: organize test directories by test ID
  block: decouple secure erase size limit from discard size limit
  block: remove redundant kill_bdev() call in set_blocksize()
  blk-mq: add documentation for new queue attribute async_dpeth
  block, bfq: convert to use request_queue->async_depth
  mq-deadline: covert to use request_queue->async_depth
  kyber: covert to use request_queue->async_depth
  blk-mq: add a new queue sysfs attribute async_depth
  blk-mq: factor out a helper blk_mq_limit_depth()
  blk-mq-sched: unify elevators checking for async requests
  block: convert nr_requests to unsigned int
  block: don't use strcpy to copy blockdev name
  blk-mq-debugfs: warn about possible deadlock
  blk-mq-debugfs: add missing debugfs_mutex in blk_mq_debugfs_register_hctxs()
  blk-mq-debugfs: remove blk_mq_debugfs_unregister_rqos()
  blk-mq-debugfs: make blk_mq_debugfs_register_rqos() static
  blk-rq-qos: fix possible debugfs_mutex deadlock
  blk-mq-debugfs: factor out a helper to register debugfs for all rq_qos
  blk-wbt: fix possible deadlock to nest pcpu_alloc_mutex under q_usage_counter
  ...
2026-02-09 17:57:21 -08:00
Linus Torvalds
591beb0e3a Merge tag 'io_uring-bpf-restrictions.4-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull io_uring bpf filters from Jens Axboe:
 "This adds support for both cBPF filters for io_uring, as well as task
  inherited restrictions and filters.

  seccomp and io_uring don't play along nicely, as most of the
  interesting data to filter on resides somewhat out-of-band, in the
  submission queue ring.

  As a result, things like containers and systemd that apply seccomp
  filters, can't filter io_uring operations.

  That leaves them with just one choice if filtering is critical -
  filter the actual io_uring_setup(2) system call to simply disallow
  io_uring. That's rather unfortunate, and has limited us because of it.

  io_uring already has some filtering support. It requires the ring to
  be setup in a disabled state, and then a filter set can be applied.
  This filter set is completely bi-modal - an opcode is either enabled
  or it's not. Once a filter set is registered, the ring can be enabled.
  This is very restrictive, and it's not useful at all to systemd or
  containers which really want both broader and more specific control.

  This first adds support for cBPF filters for opcodes, which enables
  tighter control over what exactly a specific opcode may do. As
  examples, specific support is added for IORING_OP_OPENAT/OPENAT2,
  allowing filtering on resolve flags. And another example is added for
  IORING_OP_SOCKET, allowing filtering on domain/type/protocol. These
  are both common use cases. cBPF was chosen rather than eBPF, because
  the latter is often restricted in containers as well.

  These filters are run post the init phase of the request, which allows
  filters to even dip into data that is being passed in struct in user
  memory, as the init side of requests make that data stable by bringing
  it into the kernel. This allows filtering without needing to copy this
  data twice, or have filters etc know about the exact layout of the
  user data. The filters get the already copied and sanitized data
  passed.

  On top of that support is added for per-task filters, meaning that any
  ring created with a task that has a per-task filter will get those
  filters applied when it's created. These filters are inherited across
  fork as well. Once a filter has been registered, any further added
  filters may only further restrict what operations are permitted.

  Filters cannot change the return value of an operation, they can only
  permit or deny it based on the contents"

* tag 'io_uring-bpf-restrictions.4-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
  io_uring: allow registration of per-task restrictions
  io_uring: add task fork hook
  io_uring/bpf_filter: add ref counts to struct io_bpf_filter
  io_uring/bpf_filter: cache lookup table in ctx->bpf_filters
  io_uring/bpf_filter: allow filtering on contents of struct open_how
  io_uring/net: allow filtering on IORING_OP_SOCKET data
  io_uring: add support for BPF filtering for opcode restrictions
2026-02-09 17:31:17 -08:00
Linus Torvalds
26c9342bb7 Merge tag 'pull-filename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs 'struct filename' updates from Al Viro:
 "[Mostly] sanitize struct filename handling"

* tag 'pull-filename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (68 commits)
  sysfs(2): fs_index() argument is _not_ a pathname
  alpha: switch osf_mount() to strndup_user()
  ksmbd: use CLASS(filename_kernel)
  mqueue: switch to CLASS(filename)
  user_statfs(): switch to CLASS(filename)
  statx: switch to CLASS(filename_maybe_null)
  quotactl_block(): switch to CLASS(filename)
  chroot(2): switch to CLASS(filename)
  move_mount(2): switch to CLASS(filename_maybe_null)
  namei.c: switch user pathname imports to CLASS(filename{,_flags})
  namei.c: convert getname_kernel() callers to CLASS(filename_kernel)
  do_f{chmod,chown,access}at(): use CLASS(filename_uflags)
  do_readlinkat(): switch to CLASS(filename_flags)
  do_sys_truncate(): switch to CLASS(filename)
  do_utimes_path(): switch to CLASS(filename_uflags)
  chdir(2): unspaghettify a bit...
  do_fchownat(): unspaghettify a bit...
  fspick(2): use CLASS(filename_flags)
  name_to_handle_at(): use CLASS(filename_uflags)
  vfs_open_tree(): use CLASS(filename_uflags)
  ...
2026-02-09 16:58:28 -08:00
Steven Rostedt
b4bade506b tracing: Move d_max_latency out of CONFIG_FSNOTIFY protection
The tracing_max_latency shouldn't be limited if CONFIG_FSNOTIFY is defined
or not and it was moved out of that protection to be always available with
CONFIG_TRACER_MAX_TRACE. All was moved out except the dentry descriptor
for it (d_max_latency) and it failed to build on some configs.

Move that out of the CONFIG_FSNOTIFY protection too.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20260209194631.788bfc85@fedora
Fixes: ba73713da5 ("tracing: Clean up use of trace_create_maxlat_file()")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202602092133.fTdojd95-lkp@intel.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-09 19:52:37 -05:00
Linus Torvalds
9e355113f0 Merge tag 'vfs-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
 "This contains a mix of VFS cleanups, performance improvements, API
  fixes, documentation, and a deprecation notice.

  Scalability and performance:

   - Rework pid allocation to only take pidmap_lock once instead of
     twice during alloc_pid(), improving thread creation/teardown
     throughput by 10-16% depending on false-sharing luck. Pad the
     namespace refcount to reduce false-sharing

   - Track file lock presence via a flag in ->i_opflags instead of
     reading ->i_flctx, avoiding false-sharing with ->i_readcount on
     open/close hot paths. Measured 4-16% improvement on 24-core
     open-in-a-loop benchmarks

   - Use a consume fence in locks_inode_context() to match the
     store-release/load-consume idiom, eliminating a hardware fence on
     some architectures

   - Annotate cdev_lock with __cacheline_aligned_in_smp to prevent
     false-sharing

   - Remove a redundant DCACHE_MANAGED_DENTRY check in
     __follow_mount_rcu() that never fires since the caller already
     verifies it, eliminating a 100% mispredicted branch

   - Fix a 100% mispredicted likely() in devcgroup_inode_permission()
     that became wrong after a prior code reorder

  Bug fixes and correctness:

   - Make insert_inode_locked() wait for inode destruction instead of
     skipping, fixing a corner case where two matching inodes could
     exist in the hash

   - Move f_mode initialization before file_ref_init() in alloc_file()
     to respect the SLAB_TYPESAFE_BY_RCU ordering contract

   - Add a WARN_ON_ONCE guard in try_to_free_buffers() for folios with
     no buffers attached, preventing a null pointer dereference when
     AS_RELEASE_ALWAYS is set but no release_folio op exists

   - Fix select restart_block to store end_time as timespec64, avoiding
     truncation of tv_sec on 32-bit architectures

   - Make dump_inode() use get_kernel_nofault() to safely access inode
     and superblock fields, matching the dump_mapping() pattern

  API modernization:

   - Make posix_acl_to_xattr() allocate the buffer internally since
     every single caller was doing it anyway. Reduces boilerplate and
     unnecessary error checking across ~15 filesystems

   - Replace deprecated simple_strtoul() with kstrtoul() for the
     ihash_entries, dhash_entries, mhash_entries, and mphash_entries
     boot parameters, adding proper error handling

   - Convert chardev code to use guard(mutex) and __free(kfree) cleanup
     patterns

   - Replace min_t() with min() or umin() in VFS code to avoid silently
     truncating unsigned long to unsigned int

   - Gate LOOKUP_RCU assertions behind CONFIG_DEBUG_VFS since callers
     already check the flag

  Deprecation:

   - Begin deprecating legacy BSD process accounting (acct(2)). The
     interface has numerous footguns and better alternatives exist
     (eBPF)

  Documentation:

   - Fix and complete kernel-doc for struct export_operations, removing
     duplicated documentation between ReST and source

   - Fix kernel-doc warnings for __start_dirop() and ilookup5_nowait()

  Testing:

   - Add a kunit test for initramfs cpio handling of entries with
     filesize > PATH_MAX

  Misc:

   - Add missing <linux/init_task.h> include in fs_struct.c"

* tag 'vfs-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
  posix_acl: make posix_acl_to_xattr() alloc the buffer
  fs: make insert_inode_locked() wait for inode destruction
  initramfs_test: kunit test for cpio.filesize > PATH_MAX
  fs: improve dump_inode() to safely access inode fields
  fs: add <linux/init_task.h> for 'init_fs'
  docs: exportfs: Use source code struct documentation
  fs: move initializing f_mode before file_ref_init()
  exportfs: Complete kernel-doc for struct export_operations
  exportfs: Mark struct export_operations functions at kernel-doc
  exportfs: Fix kernel-doc output for get_name()
  acct(2): begin the deprecation of legacy BSD process accounting
  device_cgroup: remove branch hint after code refactor
  VFS: fix __start_dirop() kernel-doc warnings
  fs: Describe @isnew parameter in ilookup5_nowait()
  fs/namei: Remove redundant DCACHE_MANAGED_DENTRY check in __follow_mount_rcu
  fs: only assert on LOOKUP_RCU when built with CONFIG_DEBUG_VFS
  select: store end_time as timespec64 in restart block
  chardev: Switch to guard(mutex) and __free(kfree)
  namespace: Replace simple_strtoul with kstrtoul to parse boot params
  dcache: Replace simple_strtoul with kstrtoul in set_dhash_entries
  ...
2026-02-09 15:13:05 -08:00
Linus Torvalds
bcc8fd3e15 Merge tag 'lsm-pr-20260203' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm
Pull lsm updates from Paul Moore:

 - Unify the security_inode_listsecurity() calls in NFSv4

   While looking at security_inode_listsecurity() with an eye towards
   improving the interface, we realized that the NFSv4 code was making
   multiple calls to the LSM hook that could be consolidated into one.

 - Mark the LSM static branch keys as static - this helps resolve some
   sparse warnings

 - Add __rust_helper annotations to the LSM and cred wrapper functions

 - Remove the unsused set_security_override_from_ctx() function

 - Minor fixes to some of the LSM kdoc comment blocks

* tag 'lsm-pr-20260203' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  lsm: make keys for static branch static
  cred: remove unused set_security_override_from_ctx()
  rust: security: add __rust_helper to helpers
  rust: cred: add __rust_helper to helpers
  nfs: unify security_inode_listsecurity() calls
  lsm: fix kernel-doc struct member names
2026-02-09 10:16:48 -08:00
Linus Torvalds
698749164a Merge tag 'audit-pr-20260203' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:

 - Improve the NETFILTER_PKT audit records

   Add source and destination ports to the NETFILTER_PKT audit records
   while also consolidating a lot of the code into a new, singular
   audit_log_nf_skb() function. This new approach to structuring the
   NETFILTER_PKT record generation should eliminate some unnecessary
   overhead when audit is not built into the kernel.

 - Update the audit syscall classifier code

   Add the listxattrat(), getxattrat(), and fchmodat2() syscall to the
   audit code which classifies syscalls into categories of operations,
   e.g. "read" or "change attributes".

 - Move the syscall classifier declarations into audit_arch.h

   Shuffle around some header file declarations to resolve some sparse
   warnings.

* tag 'audit-pr-20260203' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: move the compat_xxx_class[] extern declarations to audit_arch.h
  audit: add missing syscalls to read class
  audit: include source and destination ports to NETFILTER_PKT
  audit: add audit_log_nf_skb helper function
  audit: add fchmodat2() to change attributes class
2026-02-09 10:13:03 -08:00
Linus Torvalds
ef852baaf6 Merge tag 'rcu.release.v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux
Pull RCU updates from Boqun Feng:

 - RCU Tasks Trace:

   Re-implement RCU tasks trace in term of SRCU-fast, not only more than
   500 lines of code are saved because of the reimplementation, a new
   set of API, rcu_read_{,un}lock_tasks_trace(), becomes possible as
   well. Compared to the previous rcu_read_{,un}lock_trace(), the new
   API avoid the task_struct accesses thanks to the SRCU-fast semantics.

   As a result, the old rcu_read{,un}lock_trace() API is now deprecated.

 - RCU Torture Test:
    - Multiple improvements on kvm-series.sh (parallel run and
      progress showing metrics)
    - Add context checks to rcu_torture_timer()
    - Make config2csv.sh properly handle comments in .boot files
    - Include commit discription in testid.txt

 - Miscellaneous RCU changes:
    - Reduce synchronize_rcu() latency by reporting GP kthread's
      CPU QS early
    - Use suitable gfp_flags for the init_srcu_struct_nodes()
    - Fix rcu_read_unlock() deadloop due to softirq
    - Correctly compute probability to invoke ->exp_current()
      in rcutorture
    - Make expedited RCU CPU stall warnings detect stall-end races

 - RCU nocb:
    - Remove unnecessary WakeOvfIsDeferred wake path and callback
      overload handling
    - Extract nocb_defer_wakeup_cancel() helper

* tag 'rcu.release.v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (25 commits)
  rcu/nocb: Extract nocb_defer_wakeup_cancel() helper
  rcu/nocb: Remove dead callback overload handling
  rcu/nocb: Remove unnecessary WakeOvfIsDeferred wake path
  rcu: Reduce synchronize_rcu() latency by reporting GP kthread's CPU QS early
  srcu: Use suitable gfp_flags for the init_srcu_struct_nodes()
  rcu: Fix rcu_read_unlock() deadloop due to softirq
  rcutorture: Correctly compute probability to invoke ->exp_current()
  rcu: Make expedited RCU CPU stall warnings detect stall-end races
  rcutorture: Add --kill-previous option to terminate previous kvm.sh runs
  rcutorture: Prevent concurrent kvm.sh runs on same source tree
  torture: Include commit discription in testid.txt
  torture: Make config2csv.sh properly handle comments in .boot files
  torture: Make kvm-series.sh give run numbers and totals
  torture: Make kvm-series.sh give build numbers and totals
  torture: Parallelize kvm-series.sh guest-OS execution
  rcutorture: Add context checks to rcu_torture_timer()
  rcutorture: Test rcu_tasks_trace_expedite_current()
  srcu: Create an rcu_tasks_trace_expedite_current() function
  checkpatch: Deprecate rcu_read_{,un}lock_trace()
  rcu: Update Requirements.rst for RCU Tasks Trace
  ...
2026-02-09 09:46:26 -08:00
Steven Rostedt
c4f1fe47b1 tracing: Better separate SNAPSHOT and MAX_TRACE options
The latency tracers (scheduler, irqsoff, etc) were created when tracing
was first added. These tracers required a "snapshot" buffer that was the
same size as the ring buffer being written to. When a new max latency was
hit, the main ring buffer would swap with the snapshot buffer so that the
trace leading up to the latency would be saved in the snapshot buffer (The
snapshot buffer is never written to directly and the data within it can be
viewed without fear of being overwritten).

Later, a new feature was added to allow snapshots to be taken by user
space or even event triggers. This created a "snapshot" file that allowed
users to trigger a snapshot from user space to save the current trace.

The config for this new feature (CONFIG_TRACER_SNAPSHOT) would select the
latency tracer config (CONFIG_TRACER_MAX_LATENCY) as it would need all the
functionality from it as it already existed. But this was incorrect. As
the snapshot feature is really what the latency tracers need and not the
other way around.

Have CONFIG_TRACER_MAX_TRACE select CONFIG_TRACER_SNAPSHOT where the
tracers that needs the max latency buffer selects the TRACE_MAX_TRACE
which will then select TRACER_SNAPSHOT.

Also, go through trace.c and trace.h and make the code that only needs the
TRACER_MAX_TRACE protected by that and the code that always requires the
snapshot to be protected by TRACER_SNAPSHOT.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208183856.767870992@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:13 -05:00
Steven Rostedt
e4c1a09afb tracing: Add tracer_uses_snapshot() helper to remove #ifdefs
Instead of having #ifdef CONFIG_TRACER_MAX_TRACE around every access to
the struct tracer's use_max_tr field, add a helper function for that
access and if CONFIG_TRACER_MAX_TRACE is not configured it just returns
false.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208183856.599390238@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:13 -05:00
Steven Rostedt
694b3f6fe0 tracing: Rename trace_array field max_buffer to snapshot_buffer
When tracing was first added, there were latency tracers that would take a
snapshot of the current trace when a new max latency was hit. This
snapshot buffer was called "max_buffer". Since then, a snapshot feature
was added that allowed user space or event triggers to trigger a snapshot
of the current buffer using the same max_buffer of the trace_array.

As this snapshot buffer now has a more generic use case, calling it
"max_buffer" is confusing. Rename it to snapshot_buffer.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208183856.428446729@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:13 -05:00
Steven Rostedt
98021e37d6 tracing: Move pid filtering into trace_pid.c
The trace.c file was a dumping ground for most tracing code. Start
organizing it better by moving various functions out into their own files.
Move the PID filtering functions from trace.c into its own trace_pid.c
file.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032450.998330662@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:13 -05:00
Steven Rostedt
27931ee8f4 tracing: Move trace_printk functions out of trace.c and into trace_printk.c
The file trace.c has become a catchall for most things tracing. Start
making it smaller by breaking out various aspects into their own files.

Move the functions associated to the trace_printk operations out of trace.c and
into trace_printk.c.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032450.828744197@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:12 -05:00
Steven Rostedt
af1eea12ad tracing: Use system_state in trace_printk_init_buffers()
The function trace_printk_init_buffers() is used to expand tha
trace_printk buffers when trace_printk() is used within the kernel or in
modules. On kernel boot up, it holds off from starting the sched switch
cmdline recorder, but will start it immediately when it is added by a
module.

Currently it uses a trick to see if the global_trace buffer has been
allocated or not to know if it was called by module load or not. But this
is more of a hack, and can not be used when this code is moved out of
trace.c. Instead simply look at the system_state and if it is running then
it is know that it could only be called by module load.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032450.660237094@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:12 -05:00
Steven Rostedt
f377912b3d tracing: Have trace_printk functions use flags instead of using global_trace
The trace.c file has become a dumping ground for all tracing code and has
become quite large. In order to move the trace_printk functions out of it
these functions can not access global_trace directly, as that is something
that needs to stay static in trace.c.

Instead of testing the trace_array tr pointer to &global_trace, test the
tr->flags to see if TRACE_ARRAY_FL_GLOBAL set.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032450.491116245@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:12 -05:00
Steven Rostedt
93c88d06ac tracing: Make tracing_update_buffers() take NULL for global_trace
The trace.c file has become a dumping ground for all tracing code and has
become quite large. In order to move the trace_printk functions out of it
these functions can not access global_trace directly, as that is something
that needs to stay static in trace.c.

Have tracing_update_buffers() take NULL for its trace_array to denote it
should work on the global_trace top level trace_array allows that function
to be used outside of trace.c and still update the global_trace
trace_array.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032450.318864210@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:12 -05:00
Steven Rostedt
1c53d781d4 tracing: Make printk_trace global for tracing system
The printk_trace is used to determine which trace_array trace_printk()
writes to. By making it a global variable among the tracing subsystem it
will allow the trace_printk functions to be moved out of trace.c and still
have direct access to that variable.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032450.144525891@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:12 -05:00
Steven Rostedt
3e6c8f80e5 tracing: Move ftrace_trace_stack() out of trace.c and into trace.h
The file trace.c has become a catchall for most things tracing. Start
making it smaller by breaking out various aspects into their own files.

Make ftrace_trace_stack() into a static inline that tests if stack tracing
is enabled and if so to call __ftrace_trace_stack() to do the stack trace.
This keeps the test inlined in the fast paths and only does the function
call if stack tracing is enabled.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032449.974218132@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:12 -05:00
Steven Rostedt
0e730bc067 tracing: Move __trace_buffer_{un}lock_*() functions to trace.h
The file trace.c has become a catchall for most things tracing. Start
making it smaller by breaking out various aspects into their own files.

Move the __always_inline functions __trace_buffer_lock_reserve(),
__trace_buffer_unlock_commit() and trace_event_setup() into trace.h.

The trace.c file will be split up and these functions will be used in more
than one of these files. As they are already __always_inline they can
easily be moved into the trace.h header file.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032449.813550600@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:11 -05:00
Steven Rostedt
a4f77ffc8e tracing: Make tracing_selftest_running global to the tracing subsystem
The file trace.c has become a catchall for most things tracing. Start
making it smaller by breaking out various aspects into their own files.

Make the variable tracing_selftest_running global so that it can be used
by other files in the tracing subsystem and trace.c can be split up.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032449.648932796@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:11 -05:00
Steven Rostedt
64dee86ad7 tracing: Make tracing_disabled global for tracing system
The tracing_disabled variable is set to one on boot up to prevent some
parts of tracing to access the tracing infrastructure before it is set up.
It also can be set after boot if an anomaly is discovered.

It is currently a static variable in trace.c and can be accessed via a
function call trace_is_disabled(). There's really no reason to use a
function call as the tracing subsystem should be able to access it
directly.

By making the variable accessed directly, code can be moved out of trace.c
without adding overhead of a function call to see if tracing is disabled
or not.

Make tracing_disabled global and remove the tracing_is_disabled() helper
function. Also add some "unlikely()"s around tracing_disabled where it's
checked in hot paths.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260208032449.483690153@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:11 -05:00
Steven Rostedt
ba73713da5 tracing: Clean up use of trace_create_maxlat_file()
In trace.c, the function trace_create_maxlat_file() is defined behind the
 #ifdef CONFIG_TRACER_MAX_TRACE block. The #else part defines it as:

 #define trace_create_maxlat_file(tr, d_tracer)				\
	trace_create_file("tracing_max_latency", TRACE_MODE_WRITE,	\
			  d_tracer, tr, &tracing_max_lat_fops)

But the one place that it it used has:

 #ifdef CONFIG_TRACER_MAX_TRACE
	trace_create_maxlat_file(tr, d_tracer);
 #endif

Which is pointless and also wrong!

It only gets created when both CONFIG_TRACE_MAX_TRACE and CONFIG_FS_NOTIFY
is defined, but the file itself should not be dependent on
CONFIG_FS_NOTIFY. Always create that file when TRACE_MAX_TRACE is defined
regardless if FS_NOTIFY is or is not.

Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Link: https://patch.msgid.link/20260207191101.0e014abd@robin
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:11 -05:00
Steven Rostedt
326669faf3 tracing: Move tracing_set_filter_buffering() into trace_events_hist.c
The function tracing_set_filter_buffering() is only used in
trace_events_hist.c. Move it to that file and make it static.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20260206195936.617080218@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:01:11 -05:00
Steven Rostedt
c8b039c3e3 tracing: Have all triggers expect a file parameter
When the triggers were first created, they may not have had a file
parameter passed to them and things needed to be done generically.

But today, all triggers have a file parameter passed to them. Remove the
generic code and add a "if (WARN_ON_ONCE(!file))" to each trigger.

Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Link: https://patch.msgid.link/20260206101351.609d8906@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-02-08 21:00:57 -05:00