2959 Commits
Author SHA1 Message Date
Linus Torvalds 90b754d401 Merge tag 'bootconfig-v7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull bootconfig updates from Masami Hiramatsu:
 "Parser robustness and validation improvements:

   - Skip printing early params to cmdline from bootconfig

     Suppress early_param keys from /proc/cmdline and warn the user,
     since bootconfig does not invoke early_param handlers and silently
     ignoring them is misleading

   - Reject unexpected data after null character

     Detect and reject non-null data following an intermediate null
     character in the bootconfig buffer, preventing silently ignored
     configuration after an early termination

  Code cleanups:

   - Merge _xbc_exit() into xbc_exit()

     Since memblock_free() now handles late freeing and NULL addresses,
     the separate _xbc_exit() helper and its early argument are
     unnecessary. Inline it into xbc_exit()

   - Remove redundant assignment in xbc_parse_array()

     The node->child = 0 assignment after the loop duplicates what
     xbc_init_node() already did

   - Skip internal tree sanity checks in kernel

     Move the node index bounds loop from xbc_verify_tree() into a
     userspace-only xbc_sanity_check_tree() to reduce boot-time
     overhead, since out-of-bounds indices cannot be produced by
     malformed input

   - Move BOOTCONFIG_FOOTER_SIZE to include/linux/bootconfig.h

     Share the footer size constant between kernel and user-space tools,
     replacing the hardcoded (BOOTCONFIG_MAGIC_LEN + 8) expression in
     init/main.c

  Tooling improvements:

   - Remove unused PAGE_SIZE macro from the bootconfig tool

   - Consolidate xbc_init() to error message wrapper

     Use init_xbc_with_error() for all bootconfig initialization paths
     in the tool for simpler and more consistent error handling"

* tag 'bootconfig-v7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  bootconfig: Move BOOTCONFIG_FOOTER_SIZE to include/linux/bootconfig.h
  bootconfig: Skip internal tree sanity checks in kernel
  tools/bootconfig: Consolidate xbc_init() to error message wrapper
  bootconfig: Reject unexpected data after null character
  bootconfig: Skip printing early params to cmdline from bootconfig
  tools/bootconfig: remove unused PAGE_SIZE macro
  bootconfig: remove redundant assignment in xbc_parse_array()
  bootconfig: merge _xbc_exit() into xbc_exit()
2026-10-23 12:20:54 -10:00
Linus Torvalds 98aec86f8c Merge tag 'sched_ext-for-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext
Pull sched_ext updates from Tejun Heo:

 - Proxy execution can now be enabled together with sched_ext. A BPF
   scheduler can opt in to receive mutex-blocked tasks that donate their
   scheduling context to the lock owner and place them itself.

 - Lazy preemption: a BPF scheduler can preempt or kick a CPU lazily,
   deferring the switch to the next return to user space or tick, as the
   fair class can.

 - Sub-schedulers: a parent now learns which child runs on each CPU it
   delegated and when a cap change takes effect. A detaching child loses
   its caps before the parent restores the CPUs.

 - New kfuncs re-enqueue single tasks from a dispatch queue iteration
   and report a cgroup's CPU count and a CID's NUMA node. The CID
   topology now includes clusters.

 - Hot path optimizations: dispatch queue and task lookups compare keys
   inline, remote task moves no longer take a dispatch queue lock twice,
   and sub-scheduler hooks cost nothing without sub-schedulers.

 - Kfuncs callable from tracing programs are hardened against NMI and
   IRQ nesting, which could hard-lock the CPU or pick a wrong idle CPU.

 - Built-in dispatch queues no longer allocate per-CPU state that grew
   with the square of the CPU count.

 - Header syncs with the scx repo, a BTF workaround for pahole 1.32, and
   selftest fixes and coverage.

* tag 'sched_ext-for-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (69 commits)
  sched_ext: Drop the locks periodically while walking a user DSQ for re-enqueue
  sched_ext: scx_qmap: Also re-enqueue stranded tasks with scx_bpf_dsq_reenq_task()
  sched_ext: Add scx_bpf_dsq_reenq_task() to re-enqueue single tasks from a DSQ iteration
  sched_ext: Factor out the rq lock switch of scx_dsq_move()
  sched_ext: Don't queue balance callbacks from a core-sched pick
  sched_ext: Don't leave balance callbacks queued across a pick retry
  sched_ext: Fix a bypassed task stalling on a cpu its scheduler has no caps on
  sched_ext: Fix the running task keeping its protection into bypass
  sched_ext: Fix use-after-free of a local reenq node left on an inactive cpu
  sched_ext: Keep proxy donors with slice left on the local DSQ
  selftests/sched_ext: Report reload_loop attach failures
  selftests/sched_ext: Bound exit waits
  selftests/sched_ext: Add SCX_ASSERT_ALIVE and adopt it
  selftests/sched_ext: Fail loudly when EXIT_KIND is missing from BTF
  sched_ext: Add SCX_ECODE_RSN_CGROUP_OFFLINE to user_exit_info.h
  selftests/sched_ext: Fix reload_loop error-path use-after-free
  selftests/sched_ext: Fix build error in dequeue_remote selftest
  sched_ext: scx_qmap: Reset a child's cpuperf targets once its PERF revoke takes effect
  sched_ext: Add ops.sub_child_ecaps_updated() to report a child's effective cap changes
  sched_ext: scx_qmap: Show actual cid use per participant
  ...
2026-10-22 10:37:35 -10:00
Linus Torvalds bb29b957ea Merge tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux
Pull Kbuild / Kconfig updates from Nathan Chancellor:
 "Kbuild:

   - Suppress compiler flags in debug info for external module builds

   - Use '-fmacro-prefix-map' in more places in the build

   - Merge initial set of changes from Lorenzo's speed up series, along
     with some fixes found through testing:

     - Avoid allocating .modinfo in vmlinux

     - Speed up kallsyms by indexing symbols by token and outputting
       binary data to disk directly then including in assembly via
       .incbin

     - Don't sort $(NM) output when unnecessary

     - Only emit relocations on the final vmlinx link

     - Reimplement mksysmap in C

     - Move many cc-option and ld-option calls into the Kconfig stage to
       cache their results

     - Use pigz for gzip compression when available

   - Move gen_init_cpio and gen_initramfs.sh from usr/ to scripts/

   - Add a TOML configuration to scripts/container and update
     documentation accordingly

   - Add a generic, opt-in mechanism for checking that headers can
     compile standalone

   - Update machine function splitting argument for LLVM 24 rename in
     AutoFDO build

   - Miscellaneous minor clean ups, fixes, and hardening, mostly
     found/fixed via LLMs

  Kconfig:

   - Turn recursive ranges into an error

   - Fix savedefconfig for defaults that were adjusted for being out of
     range and revert a previously applied workaround

   - Improvements and hardening around integer and hexadecimal values

   - Emit a warning when selecting or implying a choice symbol, which
     has no effect

   - Emit a warning when KCONFIG_PROBABILITY is malformed

   - Introduce def_string / def_int / def_hex to mirror the existing
     def_bool / def_tristate to succinctly set a value and type at the
     same time.

   - Add cc-option-str and ld-option-str macros to act like Kbuild's
     cc-option and ld-option, returning the string when the option is
     supported, allowing many checks to be moved into Kconfig

   - Minor usability improvements to Kconfig tests"

* tag 'kbuild-7.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (59 commits)
  kbuild: AutoFDO: Update split machine function argument for upstream rename
  kbuild: Mark the initcall ordering recipe as recursive
  kbuild: Mark the gzip recipes as recursive
  localmodconfig: Explicitly report boolean configs during integrity check
  scripts/make_fit: Ignore schema checks when decomposing DTBs
  clang-tools: Import os for broken pipe handling
  kconfig: use the value argument in sym_get_near_range_bound()
  kconfig: fix infinite loop in conf_choice() when no choice value is visible
  kconfig: cleanup stale comment about 'keys' array
  kconfig: Improve ergonomics around disabling warnings with cc-option
  scripts/Kconfig.toolchain: Drop compiler symbols from dependencies
  checkkconfigsymbols.py: Parse Git status output line by line
  gen_init_cpio: stop parsing on lines with a missing argument list
  .gitignore: drop Module.markers
  .gitignore: ignore pacman package signatures
  kbuild: add header check facility as a manually run static analyzer
  Documentation: dev-tools: refer to user ID rather than id
  Documentation: dev-tools: update container.rst with config file
  scripts: add TOML config to container tool
  kconfig: tests: {old,save}defconfig: Forward dynamic keyword arguments
  ...
2026-10-21 10:45:44 -10:00
Linus Torvalds 12d5fc96eb Merge tag 'rust-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Update vendored 'zerocopy' crate to v0.8.62 (released 2026-10-08).

     This update advances 8 releases, with 3 of them carrying most of
     the changes. It contains new features as well as fixes. However,
     almost nothing has changed that requires updates on our side (a
     move of our non-ASCII change and the addition of an SPDX license
     identifier).

   - Generate Rust KUnit test suites for doctests reusing the
     '#[kunit_tests]' and '#[test]' attributes instead of C FFI
     functions, which allows to remove the generated C glue file.

     Relatedly, simplify 'kunit_assert!' by using 'file!()' and
     'line!()' inside (which doctests override as needed), which allows
     to remove the 'file' helper and 'CONFIG_RUSTC_HAS_SPAN_FILE'.

   - Trim the function names in doctests generated by 'rustdoc' < 1.95.0
     when building with 'O=', which were not reproducible.

   - Fix the 'VM_MAYSHARE' value in the generated bindings and its
     blocklist entry, due to typos.

   - Build 'core' with '--cfg no_io_statics' to ensure 'core' does not
     introduce any use of 'core::sync::atomic' into the kernel image
     since upstream Rust is moving 'std::io::Error' into 'core', which
     uses a global atomic pointer.

     Upstream Rust merged a PR to add a test checking that builds of
     'core' are warning-free with that 'cfg' enabled.

   - Enable the unstable 'proc_macro_span' feature in 'proc-macro2',
     which provides 'Span::join' and thus improves the quality of the
     diagnostics of all our procedural macros, notably 'pin-init'. This
     is only used for producing diagnostics, thus there is no hard
     reliance on the feature.

   - Globally allow 'clippy::comparison_chain', since its suggestions
     are not always ideal and upstream downgraded it to 'pedantic' too.

  'kernel' crate:

   - New 'mem' module: add the 'Align<N>' zero-sized type so that
     alignment can be specified via const generics ('repr(align(...))'
     only works with integer literals), e.g.:

         const N: usize = 128;

         struct S {
             _align: Align<N>,
         }

         assert_eq!(align_of::<S>(), N);

   - New 'ratelimit' module: add the 'Ratelimit' abstraction for 'struct
     ratelimit_state' and, based on it, the 'pr_*_ratelimited!' printing
     macros, which can be used for printing that may be triggered by
     userspace.

     In addition, convert Rust Binder to use them.

   - 'sync' module: to construct a global 'struct ratelimit_state', add
     a 'const' constructor for 'raw_spinlock_t'.

     In addition, move the lockdep types into a new 'sync::lockdep'
     submodule, since there were starting to be too many of them.

   - 'num' module: add the 'cv!' macro to create constant values ("cv")
     from an integer constant expression, with validity checked at
     compile time, inferring the target type from the context. It works
     for any type that implements the new 'FromConst' trait, e.g.:

         let a: Alignment = cv!(4096);
         let b: Bounded<u32, 4> = cv!(15);

         // Any integer constant expression works, not only literals.
         let m: NonZero<usize> = cv!(usize::MAX);

         // Checked narrowing, including in `const` items.
         const SMALL: u8 = cv!(200u32);

         // The target type can be given explicitly.
         let e = cv!(200u32 => u8);

         // With an explicit primitive target, the expression can use
         // generic parameters.
         const fn as_u64<const KEY: u16>() -> u64 {
             cv!(KEY => u64)
         }

     This avoids the verbose turbofish syntax which disincentivized
     using these types at interface boundaries (e.g.
     'Alignment::new::<8>()').

   - 'alloc' module:

       - Allow different error types in 'KBox::pin_slice()', enabling use
         of infallible initializers.

       - Add 'NumaNode::id()' accessor to retrieve the underlying NUMA
         node identifier.

   - 'time' module:

       - Add 'Delta::to_jiffies_timeout()' for use in timeout arguments.

       - Add 'Delta::as_jiffies_unsigned()'.

       - Make 'Delta::ZERO' generic over the time unit.

       - Warn and assert when passing out-of-range inputs to 'fsleep' and
         'udelay'.

       - Rename 'ClockSource' to 'ClockId' to better align with naming
         conventions in C kernel.

       - Make 'CONFIG_HZ' value available as 'bindings::HZ'.

       - Add implementation detail documentation for 'HrTimer'.

   - 'bitmap' module:

       - Add contiguous area operations ('next_zero_area{,_off}', 'set'
         and 'clear'), with extra checks compared to the underlying C
         code, plus additional ones under 'CONFIG_RUST_BITMAP_HARDENED'.
         It includes tests demonstrating the edge cases.

       - Restrict bitmap length to at most 'i32::MAX', matching
         'BitmapVec::MAX_LEN' and simplifying a few things. This also
         fixes 'u32' casts truncating in 'copy_and_extend', which could
         otherwise lead to OOB writes.

   - 'bug' module:

       - Fix 'warn_on!' on UML which called 'warn_slowpath_fmt()' with
         the wrong arguments; and fix its '// SAFETY:' comment too.

       - Add a KUnit test for 'warn_on!'.

   - 'id_pool' module: add contiguous ID reservation via the new
     'reserve_ids' and 'release_ids' methods, built on top of the new
     bitmap area operations.

   - 'sizes' module: add the sub-1K size constants ('SZ_1' to 'SZ_512')
     and implement 'SizeConstants' for 'Alignment', so that one can
     write e.g. 'Alignment::SZ_8'.

  'macros' crate:

   - Add '#[optional]' attribute for optional methods in '#[vtable]' to
     replace the 'build_error!(VTABLE_DEFAULT_ERROR)' boilerplate, e.g.:

         #[vtable]
         pub trait Operations: Sized {
             #[optional]
             fn f(&self) -> Result;
         }

     In addition, apply it to miscdevice and hide generated 'HAS_'
     constants for required methods.

   - Allow non-ASCII characters in the 'authors' field of the 'module!'
     macro, which was unintentionally restricted when multiple authors
     support was introduced.

  'pin-init' crate:

    [ Extra context from Gary's pull request:
       "This is a cycle packed with feature updates. Two of the most
        anticipated features, tuple struct support and safe self
        reference creation, has been included in this pull request.

        Safe self reference is a big one and is pushed a bit late in the
        cycle. The initial plan was to include a minimum subset for this
        cycle because I was worried about potential soundness issues;
        however during Plumbers it was agreed that the features should be
        upstreamed at once. This is because the initial users (Nova,
        JobQueue) would all need the advanced features, so it is better
        to ensure that the feature get put into use for real, and it can
        iterate with users, rather than being fully designed on paper.
        The existing safety checks are already very comprehensive, and
        Benno and I are confident that if new ones are discovered, it
        wouldn't affect the overall design.

        That said, the the usage of the advanced features (invariance,
        existential lifetime) shall be limited to the pre-agreed users
        only, so even in case where the feature needs to be reworked, the
        blast radius is limited.

        Another theme in this cycle is to improve the developer
        experience when things are used wrongly. A lot of work has been
        done to use proper spans from user-provided tokens so error
        message point to things that cause them. Many common misuse
        scenarios also gain additional custom diagnostics." ]

   - User visible changes:

       - Support tuple structs.

       - Allow safe creation of self references.

       - Vastly improve diagnostics for common misuse scenarios.

   - Other changes:

       - Use 'mixed_site' hygiene consistently.

  'MAINTAINERS':

   - Add 'RUST [BUG]' entry for the Rust 'bug' module (i.e. 'warn_on!'),
     which will be maintained by FUJITA Tomonori -- thank you!

   - Add Alice Ryhl as co-maintainer for 'Rust [ALLOC]'.

  And some other fixes, cleanups and improvements.

* tag 'rust-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (91 commits)
  rust: zerocopy: update to v0.8.62
  rust: zerocopy: fix link to upstream `README.md`
  rust: id_pool: add contiguous ID reservation
  rust: bitmap: add contiguous area operations
  rust: sizes: implement SizeConstants for Alignment
  rust: sizes: add sub-1K size constants
  rust: bitmap: restrict bitmap length to at most i32::MAX
  rust: bitmap: use function-level cfg on kunit test
  rust: num: add cv! macro to create values from constant expressions
  rust: bug: update the SAFETY comment for warn_slowpath_fmt() on UML
  rust: time: add Delta::as_jiffies_unsigned()
  rust: time: make Delta::ZERO generic over the time unit
  rust_binder: use pr_*_ratelimited! for printing
  rust: add pr_*_ratelimited! macros for printing
  rust: sync: add const constructor for raw_spinlock_t
  rust: sync: move lockdep types to rust/kernel/sync/lockdep.rs
  rust: pin-init: internal: suppress `explicit_outlives_requirements`
  MAINTAINERS: add entry for the Rust `bug` module
  rust: pin-init: internal: pin_data: support existential lifetimes
  rust: pin-init: internal: pin_data: support shared projection
  ...
2026-10-21 10:20:36 -10:00
Linus Torvalds a804c5742b Merge tag 'lsm-pr-20261016' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm
Pull lsm updates from Paul Moore:

 - Add LSM hooks, object blobs, and audit records for namespaces

   Add the necessary bits to enable LSMs to enforce access controls on
   the management of various kernel namespaces. While this pull request
   does not contain any in-tree users of these hooks, the Landlock pull
   request for Linux v7.4 will include Landlock support and the next
   merge window will likely include SELinux support as well. Considering
   the development behind these hooks, I expect that BPF LSM developers
   will also be making use of the namespace hooks, if they haven't
   already.

 - Update the inode LSM hooks to include mount idmaps

   This allows LSMs to incorporate the mount ID mapping into their
   access control decisions. While there are no current in-tree users of
   this, it was requested by those developing BPF LSM programs and this
   pull request includes a BPF LSM selftest.

 - Preserve the full 32-bit ioctl command in LSM audit records

   Previously only the low 16 bits were logged, ignoring the direction
   and size information in the upper 16 bits. The pull request also
   includes a Landlock based selftest to verify the full 32-bit ioctl
   value.

 - Ensure we don't call security_backing_file_free() multiple times

   Thankfully we don't have a problem with the current code base, but we
   want to fix this behavior now before it becomes a problem.

 - Clarify that only the current task may access current->cred

   The current code is a bit misleading around safely accessing the cred
   field in a task struct. Through comment and code corrections, this
   pull request clarifies that only the task itself may access its cred
   field.

 - Add SLAB_NO_MERGE to the credential object cache

   Harden the credential cache by ensuring credential objects live on
   dedicated slab pages.

 - Make use of safe memory zero'ing in the LSM Rust bindings

 - Update the docs for the current behavior of /sys/kernel/security/lsm

 - Update the docs for CONFIG_LSM and the "lsm=" command line option

 - Remove unnecessary code

* tag 'lsm-pr-20261016' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  lsm: remove redundant NULL check in security_init()
  selftests/landlock: Check full ioctl commands in audit records
  lsm: Preserve full ioctl commands in audit records
  doc: fix LSM ordering description for /sys/kernel/security/lsm
  doc: describe CONFIG_LSM and lsm= as the selection mechanism
  selftests/bpf: verify mount idmaps reach inode hooks
  lsm: expose mount idmaps to inode hooks
  rust: lsm: replace `core::mem::zeroed` with `pin_init::zeroed`
  cred: prevent slab cache merging for cred_jar
  lsm: don't call security_backing_file_free() multiple times
  lsm: delete duplicate assignment in lsm_prepare()
  lsm: update the BUILD_BUG_ON() in audit_log_lsm_data()
  lsm: add LSM_AUDIT_DATA_NS for namespace audit records
  lsm: add LSM blob and hooks for namespaces
  ns: Free anonymous mount namespaces via ns_common_free()
  cred: clarify that task_struct::cred is only for the current task
2026-10-20 20:04:07 -10:00
Linus Torvalds 7ed37e9d5c Merge tag 'vfs-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
 "Fixes:

   - aio: a keyed poll completion on an epoll instance could recurse
     into the same epoll waitqueue lock when the result eventfd is
     watched by that very instance. An unprivileged process could make a
     CPU spin on the recursive lock. eventfd-backed poll completions are
     always deferred now.

   - fsnotify_inoderemove() is only called once the inode is really
     dead, no nlink and no aliases, and open_by_handle_at() can't add an
     alias to a dead inode anymore. The race could crash fsnotify or
     lose inode mark notifications.

   - devtmpfs: the conversion of the public instance to ->get_tree()
     broke reconfiguring the shared superblock's options on later mounts
     which made the boot time defaults permanent. A reconfigure context
     is kept in fc->fs_private so the parse ops can forward options to
     the underlying filesystem.

   - ufs truncated the 64-bit directory size to an unsigned int in
     ufs_last_byte(). A crafted image with a 4 GiB directory produced an
     out-of-folio read in ufs_find_entry() and, with
     CONFIG_UFS_FS_WRITE, a write into an adjacent page.

   - devpts rejects max=0 instead of silently lifting the per-instance
     pty limit. The value wrapped into ida_alloc_max() and became
     unlimited.

   - fs_pin publishes pins with the rcu list helpers so the kill paths
     reading the lists under rcu see the initialization.

   - dentry_kill() reports a Tasks-RCU quiescent state. Its
     cond_resched() is the only reschedule point on the dentry teardown
     path and cond_resched() isn't a quiescent state for Tasks-RCU, so
     Meta kept seeing rcu_tasks stalls in btrfs subvolume deletion.

   - writeback sizes foreign flushes by the target wb's dirty pages
     instead of the memcg-wide count which over or undersized a single
     bdi flush.

   - nfsd READ emitted two fsnotify access events on the iterator path
     since vfs_iocb_iter_read() already sends one. A READ on a krb5i or
     krb5p mount showed up twice in inotify.

   - pipe and splice pass a poll key when waking readers and writers so
     epoll, poll() and select() waiters only wake for the event they
     asked for.

   - the iso8859-14 Unicode to charset tables had page01 duplicated as
     page1e so 29 code points mapped to the wrong bytes and 22 that
     aren't in the charset were accepted.

   - orangefs doesn't wait for an unmount service operation that never
     returns on system shutdown and uses ssize_t for strscpy() errors.

   - __register_chrdev() checks the kobject_set_name() return value.

   - selftest fixes: the openat2 tests hardcoded O_LARGEFILE to 0x8000
     which is O_NOFOLLOW on powerpc, resolve_test makes /tmp a
     mountpoint so RESOLVE_NO_XDEV has a boundary to trip over,
     file_stressor moves into its own directory with a 30 minute
     timeout, the kernfs listxattr test skips when SELinux exposes
     security.selinux, the namespaces active reference tests wait for
     the thread via a PIDFD_THREAD pidfd since pthread_join() returns
     before exit_nsproxy_namespaces(), the idmapped_tmpfile test chowns
     its directory into the mapped range, the clone3 CLONE_CLEAR_SIGHAND
     test adds CLONE_VM so it fails for the intended reason, the pidfd
     PPID error message prints the values it compares and fscontext_ns
     gets a .gitignore.

  Cleanups:

   - vmcore prints the release of the crashed kernel from the VMCOREINFO
     note so a kdump that dies before the dump lands still says which
     kernel it was for.

   - initramfs allocates hardlink hash entries with the validated cpio
     name length instead of PATH_MAX, which put every entry in
     kmalloc-8k.

   - the unused dax_layout_busy_page() is removed,
     dax_layout_busy_page_range() becomes static and dax_folio_init()
     drops a redundant list initialization.

   - vfs_empty_path() is removed, it has had no callers since
     getname_maybe_null().

   - comment and documentation fixes in aio, bpf_fs_kfuncs,
     fs-writeback, inode, read_write, squashfs and the vfs.rst copy of
     struct file_system_type"

* tag 'vfs-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits)
  selftests/filesystems: Fix idmapped_tmpfile layer dir ownership
  selftests/namespaces: Wait for thread exit via pidfd in active-ref tests
  writeback: size foreign flushes by target wb dirty pages
  initramfs: Reduce hardlink hash allocation sizes
  fs: remove unused vfs_empty_path()
  dcache: report a Tasks-RCU quiescent state in dentry_kill()
  vmcore: report the release of the crashed kernel
  splice: pass a poll key when waking pipe readers and writers
  pipe: pass a poll key when waking writers after a resize
  orangefs: use ssize_t instead of size_t for error codes...
  orangefs_super: don't wait on service operation on system shutdown.
  docs/vfs: Fix the struct file_system_type copy
  nls: fix the Unicode to charset tables of iso8859-14
  selftests/filesystems/openat2: make /tmp a mountpoint inside private namespace
  selftests/filesystems/openat2: fix O_LARGEFILE definitions for non-arm64 architectures
  fs: fix misleading comments in read_write.c
  squashfs: fix inode number description in documentation
  fs: fix typos in comments
  fs/dax: Make dax_layout_busy_page_range() static
  fs/dax: Remove unused dax_layout_busy_page()
  ...
2026-10-19 19:30:45 -10:00
Linus Torvalds e86d265826 Merge tag 'namespace-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull namespace updates from Christian Brauner:

 - Reject uid_map, gid_map and projid_map values that don't fit in a
   u32.

   map_write() parsed with simple_strtoul() and truncated modulo 2^32 on
   64-bit so "4294967301 1000 1" was installed as "5 1000 1" without an
   error. Each field is parsed with kstrtou32() now and selftests cover
   the out-of-range, negative and in-range cases. This isn't a security
   fix. The truncated values were valid ids and every later check still
   applied to them.

 - Annotate struct uid_gid_map's forward and reverse pointers with
   __counted_by_ptr and add a KUnit suite for inserting and sorting
   extents.

   insert_extent() wrote to forward[nr_extents] before bumping the count
   which the annotation flags, so it bumps first now. Two follow-up
   fixes rename the now global helpers to uid_gid_map_insert_extent()
   and uid_gid_map_sort(), since the btrfs self-tests have their own
   insert_extent(), and guard the declarations on CONFIG_KUNIT.

 - Drop the BUG_ON() NULL checks in copy_mnt_ns() and copy_utsname().
   create_new_namespaces() always passes a valid pointer and the other
   copy_*_ns() helpers don't check either.

 - Remove a dead key_put() on the create_user_ns() error path.

* tag 'namespace-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  selftests/namespaces: add uid_map/gid_map range tests
  userns: reject uid_map/gid_map values that do not fit in u32
  userns: declare the KUnit-visible helpers whenever KUnit is enabled
  userns: rename insert_extent() and sort_idmaps()
  userns: Add KUnit test suite for uid_gid_map
  userns: Add __counted_by_ptr attribute to struct uid_gid_map
  fs: namespace: drop BUG_ON() in copy_mnt_ns()
  uts: drop BUG_ON() in copy_utsname()
  userns: remove dead key_put() on the create_user_ns() error path
2026-10-19 16:09:10 -10:00
Paul Moore 436485132d Automated merge of 'lsm/dev' into 'stable-7.4'
Manual merge fixup in ns_common_types.h:ns_common to work around a conflict
with the nsfs RCU grace period fix.

* lsm/dev:
  lsm: remove redundant NULL check in security_init()
  selftests/landlock: Check full ioctl commands in audit records
  lsm: Preserve full ioctl commands in audit records
  doc: fix LSM ordering description for /sys/kernel/security/lsm
  doc: describe CONFIG_LSM and lsm= as the selection mechanism
  selftests/bpf: verify mount idmaps reach inode hooks
  lsm: expose mount idmaps to inode hooks
  rust: lsm: replace `core::mem::zeroed` with `pin_init::zeroed`
  cred: prevent slab cache merging for cred_jar
  lsm: don't call security_backing_file_free() multiple times
  lsm: delete duplicate assignment in lsm_prepare()
  lsm: update the BUILD_BUG_ON() in audit_log_lsm_data()
  lsm: add LSM_AUDIT_DATA_NS for namespace audit records
  lsm: add LSM blob and hooks for namespaces
  ns: Free anonymous mount namespaces via ns_common_free()
  cred: clarify that task_struct::cred is only for the current task
2026-10-16 17:01:58 -04:00
Masami Hiramatsu (Google) 677f83795f bootconfig: Move BOOTCONFIG_FOOTER_SIZE to include/linux/bootconfig.h
BOOTCONFIG_FOOTER_SIZE was defined locally in tools/bootconfig/main.c.
Move it to include/linux/bootconfig.h so that it can be shared with
the kernel and user-space tools. Also, use it in init/main.c instead
of the hardcoded (BOOTCONFIG_MAGIC_LEN + 8) expression when checking
the initrd size.

Link: https://lore.kernel.org/all/178913601321.248794.4786502771058559887.stgit@devnote2/

Suggested-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Sang-Heon Jeon <ekffu200098@gmail.com>
2026-10-11 10:33:40 +09:00
Masami Hiramatsu (Google) 958c01049e bootconfig: Skip printing early params to cmdline from bootconfig
If user configures `kernel.key` in bootconfig, the 'key' is shown
in kernel cmdline (/proc/cmdline) and kernel boot parameter
handler associated with 'key' is invoked. However, since the
bootconfig does not support the parameter defined with early_param,
those keys are shown in '/proc/cmdline' but not handled by kernel.

This could easily mislead users who expected to be able to specify
early parameters via the boot configuration, leading them to wonder
why it doesn't work.

Let's skip printing out early params to cmdline buffer, and warn
if there is such parameters in bootconfig.

Link: https://lore.kernel.org/all/178844899530.263905.7707547252181797215.stgit@devnote2/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-10-11 09:07:10 +09:00
Gary Guo 3504d1bce9 rust: kunit: use file!() inside kunit_assert!
This parameter is needed currently because doctests want to override the
file. Simplify it by changing it to use `file!()`. Have doctests override
`file!()` macro to achieve the current behavior.

This allows us to remove the `file` helper and associated Kconfig options.

Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260902-kunit-v2-1-eda3ed6c00c5@garyguo.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-10-03 14:04:56 +02:00
Linus Torvalds ac7445c28e Merge tag 'random-7.3-rc6-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random
Pull random number generator fixes from Jason Donenfeld:

 - VMGENID memory needs to be mapped with the decrypted tag, so that
   SEV-SNP machines can boot

 - A fix for an initialization race in VMGENID, followed by a cleanup

 - Trivial kernel doc cleanups in siphash and random.c

 - A fix for a new compilation failure with recent clang on PPC and
   RISC-V, due to generating an out-of-line memset in the vDSO

* tag 'random-7.3-rc6-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  random: vDSO: avoid call to memset() when zeroing reserved parameter
  random: fix vgetrandom_opaque_params kernel-doc
  random: vDSO: fix repeated word 'to' in comment
  siphash: clean up kernel-doc comments
  virt: vmgenid: move to using dev_set/get_drvdata
  virt: vmgenid: set driver_data before registering notification handlers
  virt: vmgenid: remap memory as decrypted
2026-10-02 11:28:45 -07:00
Nathan Chancellor eb13a1ff27 random: vDSO: avoid call to memset() when zeroing reserved parameter
After a recent change in LLVM [1], builds with the random vDSO
implementation, such as PowerPC and RISC-V, fail when checking the vDSO:

  arch/powerpc/kernel/vdso/vdso32.so.dbg: dynamic relocations are not supported
  arch/riscv/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported

memset() is now generated when zeroing params->reserved for some builds
because LLVM has an optimization (now run in more instances) that can
recognize at compile time when it is assigning a static value to a
contiguous area of memory and turn that into a call to memset(). Both
clang and GCC assume memset() is always available [2].

Clang has an internal fiddly hook, -max-store-memset, which we can set
to a high number, to disable generating out of line memset calls [3].
Similarly, GCC has -finline-stringops=memset to do the same [4], should
this issue ever hit future version of GCC. While these options wouldn't
make sense for normal kernel code, it is fine for the extremely limited
and intentionally compact vDSO code.

Link: https://github.com/llvm/llvm-project/commit/90cebef1411617fc3eedd359bdf00cb44b1c2439 [1]
Link: https://gcc.gnu.org/onlinedocs/gcc-16.2.0/gcc/Standards.html#index-ffreestanding [2]
Link: https://github.com/llvm/llvm-project/commit/b28eeb28bea39148738dc375e8a97072a1907e64 [3]
Link: https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html#index-finline-stringops [4]
Closes: https://github.com/ClangBuiltLinux/linux/issues/2183
Cc: stable@vger.kernel.org # v6.12+
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2026-10-02 12:12:13 +02:00
Andrea Righi c6fe97c34a sched: Allow enabling proxy exec with sched_ext
Now that sched_ext can handle proxy donors and BPF schedulers can opt in
to blocked-donor enqueueing with SCX_OPS_ENQ_BLOCKED, remove the
!SCHED_CLASS_EXT dependency from SCHED_PROXY_EXEC and allow both options
to be enabled together.

Acked-by: John Stultz <jstultz@google.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-09-28 09:48:05 -10:00
Lorenzo Stoakes (ARM) f85147b291 kbuild: move the toolchain checks into scripts/Kconfig.toolchain
init/Kconfig opens with two hundred lines identifying the compiler,
assembler, linker and rustc and probing which options they support, none of
it to do with init.

Move them into their own file, sourced from the top of init/Kconfig, so
that the next commit can add to them without growing init/Kconfig further.

Also update MAINTAINERS to put the new file in the KCONFIG entry.

No functional change intended.

Assisted-by: LLM
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Link: https://patch.msgid.link/20260923-build-speedup-v4-11-73128809a4a4@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2026-09-26 00:16:36 +01:00
Thorsten Blum b53f422491 initramfs: Reduce hardlink hash allocation sizes
Each hardlink hash entry reserves N_ALIGN(PATH_MAX) bytes for its name.
This makes every allocation larger than 4 KiB, placing it in the
kmalloc-8k bucket even for short names.

Use a flexible array with the already validated cpio name_len to reduce
allocation sizes.

Also use const for the read-only name parameter.

Signed-off-by: Thorsten Blum <blum@kernel.org>
Link: https://patch.msgid.link/20260919213859.24667-3-blum@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-25 17:17:42 +02:00
Linus Torvalds 6a0b3fb48d Merge tag 'bootconfig-fixes-v7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull bootconfig fixes from Masami Hiramatsu:
 "Fix integer overflow and truncation in size checks.

   - Fix size check bypasses caused by integer overflow and truncation
     when parsing initrd or standalone bootconfig files, preventing
     buffer overflow and out-of-bounds writes in the userspace tool.

   - Fix pointer arithmetic wrap-around in get_boot_config_from_initrd()
     when handling crafted huge size values, preventing fatal kernel
     page faults during early boot"

* tag 'bootconfig-fixes-v7.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  bootconfig: Fix integer overflow in initrd size check
  tools/bootconfig: Fix integer overflow and truncation in size checks
2026-09-13 09:16:36 -07:00
Masami Hiramatsu (Google) 7812d6dab0 bootconfig: Fix integer overflow in initrd size check
Sashiko reported that in get_boot_config_from_initrd(), a crafted initrd
with a huge bootconfig size (such as 0xFFFFFFFF) can cause the pointer
arithmetic:

    data = ((void *)hdr) - size;

to wrap around on 32-bit systems (or when pointer subtraction overflows).
Because data wraps around, the subsequent bounds check:

    if ((unsigned long)data < initrd_start)

evaluates to false, bypassing the check. The kernel then calls
xbc_calc_checksum(data, size), which attempts to read 4GB of memory,
hitting unmapped pages and triggering a fatal kernel page fault during
early boot. Furthermore, on 64-bit systems with an initrd > 4.29 GB, an
unbounded 32-bit size can similarly bypass the initrd_start check.

Fix this by:
1. Ensuring the initrd is at least large enough to contain the bootconfig
   footer and verifying hdr is within the initrd bounds.
2. Checking that size does not exceed XBC_DATA_MAX and does not exceed
   the available space between initrd_start and hdr before performing
   pointer subtraction.

Link: https://lore.kernel.org/all/178905333479.213925.1358412668943562406.stgit@devnote2/

Fixes: de462e5f10 ("bootconfig: Fix to remove bootconfig data from initrd while boot")
Cc: stable@vger.kernel.org
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://lore.kernel.org/all/20260910010137.EE0431F000FF@smtp.kernel.org/
Assisted-by: Antigravity:gemini-3.8-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Sang-Heon Jeon <ekffu200098@gmail.com>
2026-09-11 23:06:10 +09:00
Linus Torvalds 5e1287972b Merge tag 'vfs-7.3-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:

 - netfs:

     - Fix an uninitialized return value in netfs_unbuffered_write()
       when preparing the first subrequest fails

     - For partial unbuffered/DIO writes return the amount transferred
       rather than an error

     - Update i_size with the amount actually written when a partial
       transfer ends in an error

     - Fix a subrequest reference leak when the io_iter ends up empty

     - Handle netfs_alloc_subrequest() failure during unbuffered writes

     - Load all readahead folios into the rolling buffer upfront and
       drop the readahead references once the first subrequest is
       dispatched

     - Mark folios for copy-to-cache while issuing subrequests

     - Fix read progress reporting

 - afs:

     - Add the missing kunmap in the error path of afs_dir_search_bucket()

     - Fix a double kunmap in afs_edit_dir_remove()

     - Don't free an existing server's endpoint state when cleaning up a
       candidate server in afs_lookup_server()

     - Unbind peers removed from a server's address list

 - ufs:

     - Load the cylinder group metadata before creating the root dentry

     - Validate the cylinder group index and rotor positions before
       caching them

     - Treat an unreadable directory block as not empty

 - exec:

     - Close the close-on-exec files before taking exec_update_lock

       Closing a file can block on the filesystem, so a hung filesystem
       blocked everything that takes exec_update_lock and a FUSE server
       inspecting the calling process could deadlock

     - Drop the bprm loader before closing bprm->file in free_bprm()

 - exit: Hold a reference to thread_pid across proc_flush_pid()

 - reboot: Fix a use-after-free on cad_pid

 - nsfs: Keep the namespace tree fields out of the rcu_head used by
   kfree_rcu()

 - nstree: Check listing permission before taking a namespace
   reference in listns()

 - super: Return 0 when a nested thaw drops its hold while other
   freezers remain

 - ext4: Don't set I_METADATA_WRITEBACK during fastcommit replay

 - adfs: Free s_fs_info in ->kill_sb()

 - autofs: Free the inode info allocated in autofs_fill_super() when
   the root inode allocation fails

 - ovl: Return EINVAL instead of EIO on a user namespace mismatch now
   that it's a plain refusal and not an internal error

 - cachefiles: Don't cast the variable-length coherency data to a
   __be64 in the coherency tracepoint

* tag 'vfs-7.3-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
  nstree: check listing permission before taking a namespace reference
  exec: do_close_on_exec() before taking exec_update_lock
  exit: hold a reference to thread_pid across proc_flush_pid
  fs: autofs: fix memory leak in autofs_fill_super()
  exec: Drop bprm loader before closing bprm->file
  afs: Clear stale peer app data after address list changes
  afs: Fix incorrect free in candidate cleanup in afs_lookup_server()
  afs: Fix double-unmap of directory block
  afs: Fix missing kunmap in afs_dir_search_bucket()
  ovl: return EINVAL instead of EIO in case of mismatched user_ns
  reboot: fix cad_pid use-after-free race
  cachefiles: Fix potential UAF/KASAN warning
  netfs: Fix read progress reporting
  netfs: Mark folios with COPY_TO_CACHE whilst issuing subreqs
  netfs: Fix readahead synchronisation issues by loading all folios upfront
  netfs: break unbuffered write when netfs_alloc_subrequest() fails
  netfs: Fix subreq ref leak
  netfs: Fix i_size update for partial transfer
  netfs: Fix error vs transferred passed to ->ki_complete()
  netfs: Fix unbuffered/DIO write partial transfer error return
  ...
2026-09-09 09:38:03 -07:00
Bill Wendling f6f1a2496b userns: Add KUnit test suite for uid_gid_map
Add a KUnit test suite to verify the insertion and sorting of mappings
in struct uid_gid_map. This test suite validates both base extent
insertion (<= 5 mappings) and extended extent insertion (> 5 mappings,
which triggers the allocation of the forward and reverse pointers).

This is especially useful for verifying that the __counted_by_ptr
attribute added to 'forward' and 'reverse' pointers works correctly
without causing any runtime bounds-checking panics or traps.

Signed-off-by: Bill Wendling <morbo@google.com>
Link: https://patch.msgid.link/20260908222734.3048684-2-morbo@google.com
Tested-by: Bradley Morgan <brads@mainlining.org>
Reviewed-by: Bradley Morgan <brads@mainlining.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-09 09:45:01 +02:00
Kees Cook 3a2c4d55e3 treewide: refresh kmalloc_obj() conversions
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci

This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.

Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.

Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-04 21:37:00 -07:00
Jann Horn b030ffaedc cred: clarify that task_struct::cred is only for the current task
The `cred` field in task_struct is currently marked as __rcu, but that's
not true: It can point to credentials from access_override_creds(), which
do not get freed with RCU delay.

What actually protects task_struct::cred is that accessing it is only
permitted for the current task (except for setting up a child during fork()
or tearing down a dead process).
(There is currently code in Smack that violates this rule, but that's a bug
and causes UAF, I have sent a separate fix for that.)

Clarify this, remove the __rcu marker, and remove RCU helpers from all
accesses to this field.

Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
[PM: style tweak in security_init(), applied fixup from JH]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2026-08-31 16:14:09 -04:00
Cen Zhang (Microsoft) 5a88f78df7 reboot: fix cad_pid use-after-free race
cad_pid is a single kernel-wide struct pid pointer. proc_do_cad_pid()
reads it and passes it to pid_vnr() without protecting the lifetime of
the referenced struct pid. A concurrent writer can replace cad_pid and
drop the final reference to the old struct pid after the reader has
loaded the pointer but before pid_vnr() has finished dereferencing it,
causing a use-after-free.

kill_cad_pid() has the same lifetime race when it passes cad_pid to
kill_pid().

At the time this issue was reported, an unprivileged user could reach the
sysctl through user and PID namespaces because cad_pid was registered in
pid_table[]. Moving cad_pid back to the global reboot sysctl table
corrected that namespace and permission mismatch, but did not fix the
underlying lifetime race.

Fix this by treating cad_pid as an RCU-protected pointer at both read
sites and by waiting for a grace period before dropping the old reference
on the write side.

call_rcu(&old_pid->rcu, ...) cannot be used here because free_pid()
also queues pid->rcu; queueing the same rcu_head twice can corrupt the
RCU callback list.

Original KASAN crash stack:
  kernel/pid.c:545 pid_nr_ns()        # reads freed pid->level
  kernel/pid.c:556 pid_vnr()          # calls pid_nr_ns()
  kernel/pid.c:775 proc_do_cad_pid()  # calls pid_vnr(cad_pid)

Fixes: 9ec52099e4 ("[PATCH] replace cad_pid by a struct pid")
Reported-by: AutonomousCodeSecurity@microsoft.com
Closes: https://lore.kernel.org/all/20260717210143.4734-1-blbllhy@gmail.com/
Link: https://lore.kernel.org/all/alz5ZYLE4kaq_v2P@redhat.com/
Link: https://lore.kernel.org/all/al4ICz9biJKtdZc4@redhat.com/
Suggested-by: Mateusz Guzik <mjguzik@gmail.com>
Suggested-by: Bradley Morgan <include@grrlz.net>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Suggested-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: stable@vger.kernel.org
Signed-off-by: Cen Zhang (Microsoft) <blbllhy@gmail.com>
Link: https://patch.msgid.link/20260814040944.16561-1-blbllhy@gmail.com
Reviewed-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-08-31 10:25:46 +02:00
Linus Torvalds 5f5ef9c407 Merge tag 'bootconfig-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull bootconfig updates from Masami Hiramatsu:

 - Support build-time command line building for embedded bootconfig

 - Fix xbc_snprint_cmdline() to render descendant keys when the root has
   both a value and subkeys, and treats empty subtrees correctly.

 - Add build-time pipeline using tools/bootconfig -C to render the
   embedded bootconfig "kernel" subtree into .init.rodata as a cmdline
   string.

 - Clean build-time tools/bootconfig from make clean

 - Add helper to prepend embedded bootconfig cmdline into
   boot_command_line early before parse_early_param()

 - Wire early prepend helper in x86 setup_arch() so early_param handlers
   see values from the embedded bootconfig (currently x86 only)

 - Avoid duplicating "kernel" keys in setup_boot_config()

 - Refactor setup_boot_config() to share bootconfig_cmdline_requested()

 - Document CONFIG_CMDLINE_FROM_BOOTCONFIG usage, requirements, and
   precedence

* tag 'bootconfig-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  init/main.c: use bootconfig_cmdline_requested() for the runtime opt-in
  bootconfig: skip runtime kernel.* render once prepended early
  x86/setup: prepend embedded bootconfig cmdline before parse_early_param
  Documentation: bootconfig: document build-time cmdline rendering
  bootconfig: add xbc_prepend_embedded_cmdline() helper
  bootconfig: clean build-time tools/bootconfig from make clean
  bootconfig: render embedded bootconfig as a kernel cmdline at build time
  bootconfig: render descendant keys when xbc_snprint_cmdline() root has a value
2026-08-25 08:59:09 -07:00
Linus Torvalds ed3b875bea Merge tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "mm: drop "sub" prefix from various places" (Dev Jain)

   page->folio conversion and a naming cleanup

 - "mm/kasan: remove redundant initialization for kasan_flag_write_only"
   (Igor Putko)

   KASAN cleanup work

 - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling)

   Small speedup in the pagecaache read code

 - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng)

   Improve the vmalloc code - mainly the avoidance of GFP_KERNEL
   allocations when the caller asked for GFP_NOFS or GFP_NOIO

 - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno
   Leitao)

   Avoid a soft lockup watchdog trigger from the kmemleak scanning code
   in extreme situations

 - "mm/page_owner: misc cleanups" (Ye Liu)

   Cleanups to the page_owner code. For some reason lots of people have
   been working on the page_owner code this cycle.

 - "mm: convert to walk_page_range_vma() to eliminate find_vma()"
   (Kefeng Wang)

   Simplify and accelerate the page walking library function

 - "mm/migrate: preparatory cleanups for batch copy and offload"
   (Shivank Garg)

   Cleanups in the migration code

 - "mm/page_owner: add per-fd filter infrastructure for print_mode and
   NUMA filtering" (Zhen Ni)

   Per-fd filtering to page_owner in order to reduce the sometimes vast
   amount of output it can produce

 - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song)

   Fixes and preparatory cleanups around bootmem HugeTLB handling,
   sparse initialization ordering, and related vmemmap setup

 - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao)

   Reduce lock contention in zs_free(), which dominates the unmap path
   under memory pressure on Android (LMK kills) and on x86 servers
   running zswap-heavy workloads.

   Up to 1.83x improvement in microbenchmarking.

 - "move alloc_tag.c file under mm/" (Suren Baghdasaryan)

 - "samples/damon: handle damon_{start,stop}() failures" (SJ Park)

   Fix improper handling of damon_start(), damon_stop(), and
   damon_call() failures across DAMON sample modules to prevent
   potential memory leaks, operation disruptions and use-after-free
   bugs

 - "mm/damon/sysfs: kobject_del() directories that users can
   create/remove" (SJ Park)

   Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE
   causeing creation failures due to duplicate directory names by adding
   missing kobject_del() calls before creating new directories

 - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand)

   Clean up the core pte handling code

 - "selftests/damon: misc fixes for test bugs" (Kunwu Chan)

   Fix several bugs in the DAMON selftests

 - "selftests/damon: fix memcg_path staging handling" (Cheng Nie)

   Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and
   add a test case for it in sysfs.py.

 - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev)

   Selftest coverage for DAMON's refresh_ms sysfs feature by updating
   the test control module and verifying that scheme stats update
   automatically without manual intervention

 - "mm/damon: five misc fixups" (Akinobu Mita)

   Miscellaneous DAMON fixups.

 - "mm/damon/core: detect internal variation above max_nr_regions/2"
   (Jiayuan Chen)

   Fix DAMON's region splitting behavior when region counts exceed half
   the maximum budget by dynamically scaling down the split fraction as
   the limit approaches, preventing large regions from staying un-split,
   and add corresponding KUnit test coverage

 - "mm: preparatory patches for PMD level swap entries" (Usama Arif)

   Refactor and clean up PMD softleaf helpers, call sites, and
   architecture flags to lay the groundwork for a follow-up series that
   introduces PMD page table swap entries

 - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ
   Park)

   Update DAMON design and ABI documentation, expands unit and selftest
   coverage, optimize damon_commit_target_regions(), and clean up
   recently added sysfs interface code for better readability

 - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2"
   (Usama Arif)

   Optimize vmpressure() by skipping unnecessary work on cgroup v2 for
   userspace event notifications and refactor v1-only eventfd handling
   into mm/memcontrol-v1.c to reduce memory overhead and code complexity

 - "selftests/mm: refactor pkey helpers and fix mmap error handling"
   (Hongfu Li)

   Refactor pkeys shared tracing and assertion helpers into a common
   file, unify protection key selftests to use consistent diagnostic
   logging and assertions, and enforce standardized MAP_FAILED return
   checks for mmap() calls across the tests

 - "mm/damon: optimize out nr_accesses_bp" (SJ Park)

   Replace the error-prone, continuously updated nr_accesses_bp field in
   damon_region with an on-demand moving sum function, reducing
   structure memory overhead and avoiding state corruption bugs

 - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng)

   Decouple HugeTLB folio allocation from VMA dependencies by
   introducing hugetlb_alloc_folio(), enabling subsystems like
   guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs

 - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park)

   Integrate DAMON's probe_hits attribute counter into the pseudo moving
   sum infrastructure, enabling real-time, online monitoring without
   waiting for full aggregation intervals

 - "mm: Some cleanups for page allocator APIs" (Brendan Jackman)

   Simplify and refactor the page allocator entry points and flags by
   unifying allocation paths, adding internal alloc_flags arguments, and
   eliminating redundant __ prefixed alloc_pages variants.

 - "Fix incorrect access of hugetlb pte entries" (Dev Jain)

   Enforce the consistent use of huge_ptep_get() instead of ptep_get()
   for HugeTLB entries and fixes an unaligned address issue in arm64's
   huge_ptep_get() implementation

 - "mm/damon: validate all parameters in the core" (SJ Park)

   Consolidate parameter validation into the DAMON core specifically
   within damon_start() and damon_commit_ctx() to centralize error
   checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency

 - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong
   Chen)

   Rename is_need() to filter_record() for clearer return semantics, fix
   per-record allocation memory leaks and bound output copies in
   search_pattern() to address an existing buffer issue

 - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen)

   Mitigate a system-wide stall which occurs when a cgroup is removed
   while one of its memory control files is doing synchronous reclaim

 - "mm/memory-failure: add panic option for unrecoverable pages" (Breno
   Leitao)

   Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl
   that immediately panics the kernel on unrecoverable memory errors in
   kernel-owned pages to preserve error context and prevent delayed,
   silent data corruption

 - "mm/damon: refactor damon_{start,stop,commit}() for simple error
   handling" (SJ Park)

   Refactor the DAMON core API functions to guarantee that all contexts
   are fully stopped when damon_start(), damon_stop(), or damon_commit()
   fail, eliminating the need for complex and error-prone caller-side
   cleanup code

 - "Keep tail page private zero at free and folio split" (Zi Yan)

   Add checks to ensure tail_page->private is zero when freeing compound
   or high-order pages and when promoting tail pages during large folio
   splits. By validating these fields at free and split time, it allows
   the removal of redundant private field clearing inside
   prep_compound_tail()

 - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry
   Song)

   Eliminate redundant lru_add_drain() calls in
   wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead

   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads

 - "mm: clean up folio LRU and swap declarations" (Jianyue Wu)

   Reorganize folio LRU and swap code by relocating page-cluster state
   to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving
   MM-internal reclaim declarations into mm/internal.h.

 - "userfaultfd: working set tracking for VM guest memory" (Kiryl
   Shutsemau)

   Add userfaultfd support for tracking the working set of VM guest
   memory, so a VMM can identify hot pages and reclaim cold ones to
   tiered or remote storage

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David
   Hildenbrand)

   Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE,
   performing some smaller cleanups around freeing of reserved vmemmap
   pages on the way.

 - "mm/damon: update probe hits for runtime parameter commits" (SJ Park)

   Ensure that DAMON's probe_hits attribute counter is properly updated
   when monitoring intervals are changed at runtime, matching the
   behavior of nr_accesses. To achieve this, it refactors and renames
   existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.

 - "KSM: performance optimizations for rmap_walk_ksm" (xu xin)

   Resolve a severe KSM reverse-mapping performance bottleneck where
   thousands of split VMAs sharing a single anon_vma cause extended lock
   contention.

   By adding an interval-filtering check during the rmap walk, it
   reduces worst-case anon_vma lock hold times from over 500ms down to
   under 2ms, preventing application freezes and latency spikes under
   memory pressure.

 - "mm: split a couple of headers from internal.h" (Mike Rapoport)

   Split declarations related to mm_init, memblock, vmalloc and sparse
   into new headers

 - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin)

   Apply the interval tree optimization from rmap_walk_ksm() to
   collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.

   It hoists loop-invariant address initialization and restricts the
   anon_vma_interval_tree_foreach walk to a targeted page offset range,
   reducing redundant checks and improving lookup efficiency.

 - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali
   Patil)

   Fix issues in the hugetlb and KSM MM selftest categories that can
   report failures when the prerequisites for the tests are not
   satisfied

 - "mm/damon: introduce data attributes only monitoring" (SJ Park)

   Introduce attribute-weighted region management in DAMON, allowing
   users to prioritize specific data attributes (such as page sizes or
   cgroups) over or instead of access monitoring.

   By assigning weights to attribute probes, DAMON can completely
   disable access tracking and adjust monitoring regions based on
   weighted probe-hit counters to optimize monitoring quality for
   attribute-focused workloads.

 - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings"
   (Stanislav Kinsburskii)

   Extend hmm_range_fault() to support userfaultfd-backed regions by
   allowing the mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.

   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd
   regions while preserving backward compatibility for existing callers.

 - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes)

   Clean up and standardize how vma->vm_pgoff is accessed and
   manipulated across file-backed and anonymous mappings in the kernel

   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while
   renaming rmap interval tree helpers to better reflect their
   functionality.

   These changes establish a cleaner foundation for future work that
   will unify virtual page offset indexing for all anonymous and CoW'd
   folios.

 - "mm: handle device-private PMDs in walk callbacks" (Usama Arif)

   Address kernel panics and state corruption caused by MM walk
   callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations

   It ensures that functions which acquire pmd_trans_huge_lock()
   properly recognize device-private PMDs instead of assuming a present
   THP or a standard migration entry.

 - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain)

   Refactor try_to_unmap_one by modularizing Hugetlb,
   anonymous-lazyfree, and anonymous-swapbacked logic into dedicated
   functions, laying the structural groundwork for batched anonymous
   large folio unmapping.

 - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu)

   Fix typos and fills in missing entries in the DAMON sysfs ABI
   document

 - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price)

   Introduce an atomic sysfs state attribute and supporting DAX/MM
   infrastructure to prevent userland races when offlining and removing
   entire memory regions

   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.

 - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes)

   Continue transitioning the kernel from the deprecated vm_flags_t type
   to vma_flags_t across core memory management infrastructure.

   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.

 - "Two small patches to clean up mm/mm_slot.h" (xu xin)

   Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate
   slot deletion sequences in khugepaged and KSM. It also adds code
   documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.

 - "mm/damon/core: hide core-private struct fields" (SJ Park)

   Clean up DAMON core structures by consistently marking internal-only
   fields with private: comment tags to prevent improper direct access
   from outer layers.

   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.

 - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races"
   (SJ Park)

   Address potential infinite loops, NULL dereferences, and race
   conditions identified in DAMON

   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.

 - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan
   Jackman)

   Fix an NMI safety flaw in __free_frozen_pages() where freeing pages
   on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks
   via non-PCP or isolated migration paths.

   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.

 - "mm/page_alloc: couple of followups for recent cleanups" (Brendan
   Jackman)

   Clean up and update page allocator nomenclature, documentation, and
   debug assertions.

   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete
   VM_BUG_ON() assertions in allocation paths.

 - "mm/mseal: further cleanups" (Lorenzo Stoakes)

   Refactor and simplify the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.

   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO,
   eliminates mm_struct parameters to enforce that sealing applies only
   to current->mm, and streamlines overall logic and comments with no
   functional changes intended.

 - "mm/vmscan: fix swappiness=max and clean up per-node proactive
   reclaim" (Ridong Chen)

   Resolve reclaim behavior bugs and clean up function parameters across
   memory reclaim paths

   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead
   of collapsing all failures into -EAGAIN, and removes the obsolete
   gfp_mask parameter from __node_reclaim().

 - "mm: mincore: misc cleanups" (Kefeng Wang)

   Clean up and simplifies the mincore code. Most importantly, it
   removes the historical special behavior that always reports VM_PFNMAP
   pages as non-resident.

 - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau)

   Two trivial cleanups in the folio split API

 - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation
   bugs" (SJ Park)

   Resolve minor operational and testing bugs in DAMON identified by
   Sashiko. It initializes the damos->last_applied field to prevent
   occasional efficiency degradation and fixes invalid memory accesses
   in DAMON KUnit tests during test failure handling.

 - "cleanup for stable_page_flags()" (Jinjiang Tu)

   Clean up and refactor stable_page_flags() used by /proc/kpageflags
   without altering functionality.

   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.

 - "Batch unmap of uffd-wp file folios" (Dev Jain)

   Extend batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching
   capabilities to pte_install_uffd_wp_if_needed().

   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.

 - "mm/early_ioremap: clarify and clean up early_ioremap_reset()"
   (Sang-Heon Jeon)

   Clarify and clean up the architecture-specific usage of
   __late_set_fixmap() and __late_clear_fixmap() after
   early_ioremap_reset()

   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset
   calls in the RISC-V and ARM64 architectures.

 - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner)

   Address severe performance regressions, swap storms, and spurious
   OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta
   production

   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.

 - "zram: lockmap tweaks" (Sebastian Siewior)

   Optimize and fix lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolate lock classes across multiple instances

   This reduces memory overhead by replacing per-entry lockdep_map
   instances with a single map per struct zram, and assigns a dynamic
   lock_class_key to each instance to prevent false deadlock reports
   when different zram devices are backed by distinct filesystems.

* tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits)
  selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check
  selftests/mm: unpoison pages in memory-failure teardown
  mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn()
  mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro
  mm/zsmalloc: fix release order of locks in zs_page_migrate()
  Documentation: zram: remove sections numbering
  ksm: stop iterating VMAs when ksm_test_exit returns true
  mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE
  mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  zram: use a custom key for each zram object
  zram: move lockmap to be per-zram instead per table
  selftests/mm: fix gup_longterm EINVAL error message
  mm: page_alloc: fix non-movable reclaim storm in defrag_mode
  mm: page_alloc: move capture_control to the page allocator
  mm: compaction: support non-movable compaction for pageblock requests
  mm: page_alloc: __GFP_FS lockdep annotation for direct compaction
  hugetlb: evaluate subpool free state while locked
  mm/damon: remove trailing semicolons after function definitions
  mm/damon/ops-common: prevent migration fallback to non-target nodes
  mm/damon: update outdated comment about DAMOS filter handling
  ...
2026-08-20 18:17:08 -07:00
Linus Torvalds 11260c335e Merge tag 'sched_ext-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext
Pull sched_ext updates from Tejun Heo:
 "Most of this cycle completes the enqueue-path support for hierarchical
  sub-scheduling, which makes sub-scheduler support feature complete: a
  root BPF scheduler can now hand a cgroup subtree over to a nested
  sub-scheduler together with revocable CPU grants, and the
  sub-scheduler owns all scheduling decisions for its tasks on those
  CPUs.

  Development volume was high and a number of changes plugging holes in
  the new support landed late in the cycle. Also included are core
  scheduling fixes that were completed too late for the v7.2 release and
  are routed through this pull request.

  Sub-scheduler CPU delegation:

   - Parent schedulers now grant and revoke per-CPU capabilities
     (enqueueing, preemption, CPU frequency control) on their children,
     enforced on every path a scheduler can reach a CPU through.
     Previously only dispatching could be delegated; this lets
     sub-schedulers fully schedule their CPUs.

   - Rescue execution: a task whose scheduler doesn't have access to the
     CPUs the task needs to run on starved until the watchdog ejected
     the whole scheduler. The kernel now runs such tasks directly on a
     small bandwidth budget, turning a scheduler-killing failure into
     bounded degradation.

   - Cgroup integration: tasks migrating across a sub-scheduler boundary
     weren't re-homed to the new owner, causing wrong-scheduler
     scheduling and a use-after-free. Sub-schedulers now take over their
     cgroup subtree and receive its cgroup callbacks.

   - Arena objects now cross the kernel/BPF boundary as typed pointer
     arguments, translated transparently by the BPF tree's new arena
     argument support, replacing untyped arguments with manual
     translation.

   - scx_qmap now demonstrates full hierarchical sub-scheduling.

  Other fixes and updates:

   - Robustness improvements: the abort path is now NMI-safe, fixing
     deadlocks when errors are raised from NMI context and making
     hardlockup recovery direct. Reenqueue loops that could monopolize a
     CPU ahead of the watchdog now eject the offending scheduler, and
     stalls are blamed on the scheduler actually responsible.

   - Hardening: BPF-writable arena memory is validated before kernel
     use, and task slice and vtime writes got explicit synchronization
     rules, closing corruption vectors open to buggy or malicious
     schedulers.

   - Core scheduling: sched_ext dispatching can drop the rq lock inside
     the core-wide pick, which let interleaving selections corrupt each
     other's state and hard-hang the machine. The selection now restarts
     when the lock was released. The task ordering callback was also
     invoked with its arguments swapped, and the default ordering is
     updated to work across sub-scheduler boundaries. The fixes are
     marked for stable.

   - Other fixes headed for stable: a task init leak on fork failure
     during enable, tooling compat macros that silently failed to detect
     newer kernels, and a crash on reenqueueing against a destroyed
     dispatch queue.

   - Tooling: scx_pair moves off deprecated callbacks, and the
     deprecated scx_bpf_cpu_rq() kfunc is removed"

* tag 'sched_ext-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (144 commits)
  sched_ext: Drop the dead SCX_DEQ_CORE_SCHED_EXEC test in dequeue_task_scx()
  sched_ext: Make core-sched task ordering hierarchy-aware
  sched_ext: Use runnable_at for the default core-sched task ordering
  sched_ext: Fix inverted ops.core_sched_before() invocation
  sched_ext: Move the config-off sub-cap kfunc stubs into sub.c
  sched_ext: Rename balance-era identifiers to dispatch terms
  sched_ext: Drop the stale keep_prev fixup in dispatch_pick()
  sched_ext: Keep kick_sync waiting on the rq's own CPU
  sched_ext: Make SCHED_CLASS_EXT select GENERIC_ALLOCATOR
  sched_ext/scx_flatcg: Fix cvtime true-up on slice expiry
  sched_ext: Don't BUG_ON a destroyed DSQ in process_deferred_reenq_users
  sched_ext: Fix scx_bpf_dsq_move_to_local___v2 compat detection
  sched_ext: Make scx_bpf_events() read the calling scheduler's counters
  sched_ext: Drop unlocked scx_rq_clock_invalidate() from scx_root_disable()
  selftests/sched_ext: Fix flaky ddsp failure tests on busy systems
  selftests/sched_ext: Make numa idle validation race-free
  sched_ext: Fix scx_bpf_dsq_reenq___compat kfunc extern prototype
  sched_ext/scx_flatcg: expire cached hweights on weight changes
  sched_ext: Fix exit_task leak on fork failure during enable
  sched_ext: fix stale references in doc comments
  ...
2026-08-20 11:01:37 -07:00
Linus Torvalds 9d2ed026f0 Merge tag 'sysctl-7.03-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl
Pull sysctl updates from Joel Granados:

 - Fix kernel-doc warnings by adjusting in file documentation

 - Consolidate do_proc_* function into do_proc_vec

   Consolidate three slightly different implementations of applying a
   converter on all elements of a vector. Fixes to this function now
   propagate to the three types.

 - Replace CONFIG_PROC_SYSCTL with CONFIG_SYSCTL (they were the same)
   and restrict cad_pid modifications to global root (GLOBAL_ROOT_UID)

* tag 'sysctl-7.03-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
  sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL
  sysctl: move the "cad_pid" entry from pid_table[] to kern_reboot_table[]
  sysctl: repair some kernel-doc comments
  sysctl: add Returns: kernel-doc for all functions
  sysctl: Update API function documentation
  sysctl: Rename proc_doulongvec_minmax_conv to proc_doulongvec_conv
  sysctl: Group proc_handler declarations and document
  sysctl: Replace do_proc_do{int,ulong,uint}vec with do_proc_vec
  sysctl: Add negp parameter to douintvec converter functions
  sysctl: Move default converter assignment out of do_proc_dointvec
2026-08-20 08:46:41 -07:00
Linus Torvalds 104a813376 Merge tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull VDSO updates from Thomas Gleixner:

 - Consolidate the VDSO datastore further and provide support for
   mlock_all() and prefaulting.

 - Provide 32-bit legacy time related functionality only if
   CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists,
   but architecture code still exposes the legacy functionality even
   disabled.

   Clean this up by adding the missing guards and validating at build
   time that the VDSO is legacy free if disabled.

 - Consolidate the VDSO related config options in core and drivers,
   which removes some non-sensical dependencies and quite an amount of
   #ifdeffery.

 - Clean up the PAGE_SIZE definition maze

* tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  random: vDSO: Drop custom PAGE_SIZE definitions
  LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/timer-riscv: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/arm_arch_timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/mips-gic-timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  MIPS: csrc-r4k: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY
  kbuild: Support generated asm-headers in subdirectories
  vdso: Rename HAVE_GENERIC_VDSO to VDSO_DATASTORE
  vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
  vdso: Automatically select HAVE_GENERIC_VDSO if necessary
  MIPS: vdso: Stop using CONFIG_HAVE_GENERIC_VDSO
  vdso: Remove the dependency on HAVE_GENERIC_VDSO from ARCH_HAS_VDSO_ARCH_DATA
  futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
  vdso/gettimeofday: Verify COMPAT_32BIT_TIME interactions
  sparc: vdso: Respect COMPAT_32BIT_TIME
  MIPS: VDSO: Respect COMPAT_32BIT_TIME
  powerpc/vdso: Respect COMPAT_32BIT_TIME
  ARM: VDSO: Respect COMPAT_32BIT_TIME
  arm64: vdso32: Respect COMPAT_32BIT_TIME
  ...
2026-08-18 16:56:25 -07:00
Linus Torvalds 3b4128b9f3 Merge tag 'timers-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer and timekeeping core updates from Thomas Gleixner:

 - Fix a subtly inconsistency in the timekeeping code, which fails to
   account for the monotonicity adjustment in ntp_error.

   For small changes of the clocksource multiplicator (+/-1) which are
   typically used by the NTP PLL this is hard to observe. But for larger
   adjustments, e.g. caused by a direct frequency setting through
   adjtimex() the one-time uncompensated offset is significant.

   Cure this by adjusting ntp_error with the resulting offset so that
   the discrepancy is smoothed away over time

 - Make tick length calculations correct in NTP.

   The timekeeping core takes the quantisation of the clocksource into
   account when calculating the tick length to compensate for the
   deviation of the nominal NTP_INTERVAL_LENGTH.

   While timekeeping gets this right, NTP is not aware of that, which
   means it operates on the nominal value and not on the actual value
   which is determined by the clock source frequency. The rounding of a
   coarse clocksource like the ACPI PM timer results in a +127 PPM
   deviation.

   Cure this by exposing the deviation to the NTP code so that it can
   operate on the same data as the timekeeping core. This is purely
   kernel internal. User space still sees the nominal tick lenght via
   adjtimex().

 - The accuracy of the NTP adjustments is fairly approximate as the code
   assumes that the invocations are precisely in NTP interval frequency
   ticks and the final adjustment can over and under-run.

   Cure this by adjusting ntp_error by the intended skew on each tick to
   achieve the desired rate.

 - Handle the two competing skews of time offset and time adjustment
   correctly by calculating the conflict portion between the skews and
   adjusting both accordingly.

 - A set of updates and improvements for the selftests

 - The usual small fixes and improvements all over the place

* tag 'timers-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  selftests: timers: nsleep-lat: Check all calls to clock_nanosleep() and clock_gettime()
  selftests: timers: nsleep-lat: Reuse kselftest error numbers
  selftests: timers: nsleep-lat: Explicitly list the tested clocks
  selftests: timers: nsleep-lat: Use NSEC_PER_MSEC define for unreasonable latency
  selftests: timers: nanosleep: Report each test separately
  selftests: timers: nanosleep: Explicitly handle timer_delete() failure
  selftests: timers: nanosleep: Move all single clock tests out of the loop in main()
  selftests: timers: nanosleep: Reuse kselftest error numbers
  selftests: timers: nanosleep: Explicitly list the tested clocks
  selftests: timers: nanosleep: Drop output alignment
  selftests: timers: Use clock_name() and constants from clock-helpers.h
  selftests: Add clock-helpers.h
  timer_list: Use ktime_t over nanoseconds
  timer_list: Use standard 'long long' format placeholders
  hrtimer: Add a lockdep assertion to hrtimer_update_base()
  timekeeping: Use u32 for clock_was_set_seq
  timekeeping: Rename clockid_aux_valid() to clockid_is_aux_clock()
  hrtimer: Account nr_retries on recovered interrupt retries
  timers/itimer: Zero-init old itimerval before copy to userspace
  nohz: Replace dead select with choice default
  ...
2026-08-18 16:23:56 -07:00
Linus Torvalds 030c9f813b Merge tag 'timers-cleanups-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull treewide timer related cleanups from Thomas Gleixner:

 - Remove the leftover CLOCK_TICK_RATE which has been scheduled for
   removal more than a decade ago along with some now empty asm/timex.h
   files.

 - Consolidate delay timer calibration

   The construct of having a define in a header requires that
   architectures provided asm/timex.h for no reason. Also the function
   name for reading the delay timer is confusing at best.

   Use a config switch to enable that functionality and rename the
   function to delay_read_timer() to make the purpose clear.

   This removes some more now empty asm/timex.h files as well.

* tag 'timers-cleanups-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  calibrate: Rework delay timer calibration
  treewide: Remove CLOCK_TICK_RATE
  x86: Use PIT_TICK_RATE instead of CLOCK_TICK_RATE
2026-08-18 15:58:29 -07:00
Linus Torvalds 1c3e8cef79 Merge tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
 "Bigger cleanups:

   - The lockref dead-count handling is tidied up.

     The open-coded check for a count below zero as the dead marker
     relies on information the caller should not have.

   - make put_mnt_ns() leave mounts connected. Destroying a mount
     namespace disconnected its mounts from their mount points. So a
     file descriptor still open on the parent of a mount point could be
     used to peek under it.

     Locked mounts were already kept connected to prevent exactly that.
     But a mount is only locked when its tree is copied across a user
     namespace boundary. So a mount namespace set up by a privileged
     component had no locked mounts and its mounts were disconnected.
     Passing UMOUNT_CONNECTED keeps every mount connected and prevents
     that bug.

   - vfs_prepare_mode() passes S_IFDIR for directories. I meant to fix
     that ago but didn't get to it. So now someone finally did it.

     This kills the exception where the mode could be 0 when a directory
     was created whereas every other creation operation passed it
     explicitly already.

   - move long delayed work for ufs, jffs2, hfsplus, hfs and affs from
     the per-cpu system_long_wq to the new unbound system_dfl_long_wq.

     None of that work relies on per-cpu state and the work item is
     enqueued with queue_delayed_work() whose timer is global anyway. So
     it may as well benefit from scheduler task placement.

  Smaller fixes and cleanups:

   - unlock_buffer() and journal_end_buffer_io_sync() use
     clear_and_wake_up_bit()

   - the pipe page pools are unified into a single per-pipe pool and the
     extra wake_up(rd_wait) is limited to EPOLLET consumers

   - eventpoll now computes its timer slack lazily in ep_poll()

   - shrink_dcache_for_umount() keeps making progress on busy roots

   - excess xarray nodes are freed in clear_inode()

   - romfs detects hard link cycles

   - the user path of nested backing files is fixed

   - pidfd holds exec_update_lock around the namespace ioctl

   - non-memcg-aware nr_cached_objects is skipped during memcg slab
     shrink

   - iomap_write_iter() always returns status

   - mangle_path() is renamed to seq_mangle_path()

   - inode timestamp accessors are annotated

   - new regression test for pipe->poll_usage.

   - a few documentation, kernel-doc and selftest fixes"

* tag 'vfs-7.3-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (67 commits)
  selftests/namespaces: Fix racy pipe handshake in timens and pidns_separate
  selftests/epoll: add a regression test for pipe->poll_usage
  pipe: only enable the extra wake_up(rd_wait) for EPOLLET consumers
  pidfd: hold exec_update_lock around namespace ioctl
  fs: fix user path of nested backing files
  fs: remove stale inode_insert5() kernel-doc parameter
  fs: fix switch/case indentation in sysfs() syscall
  fs: document semantics of kstat::{uid,gid} fields
  dcache: keep shrink_dcache_for_umount() making progress on busy roots
  seq_file: rename mangle_path to seq_mangle_path
  nstree: add/fix struct ns_id_req kernel-doc member fields
  dcache: use lockref routines for dead count checks
  lockref: tidy up dead count handling
  initramfs: fix typo in reserve_initrd_mem comment
  fs/pipe: unify the page pools into a single per-pipe pool
  fs: annotate inode timestamp accessors
  eventpoll: compute timer slack lazily in ep_poll()
  selftests/filesystems: add mntns cleanup test
  put_mnt_ns(): leave mounts connected
  affs: Move long delayed work on system_dfl_long_wq
  ...
2026-08-17 12:56:12 -07:00
Linus Torvalds fff0150b02 Merge tag 'vfs-7.3-rc1.kthread' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull kthread vfs updates from Christian Brauner:
 "This stops kernel threads from sharing filesystem state with
  userspace. This work is about 3 cycles old and has been in -next
  for about that time.

  When the kernel boots init_task creates PID 1 and then kthreadd. From
  that point every kthread and PID 1 share the same fs_struct. That is
  why pivot_root() has to rewrite the fs_struct of all kthreads. The
  rewriting exists so that kthreads can use init's filesystem state when
  they want to. It also means userspace can move the ground out from
  under the kernel.

  PID 1 now gets a completely separate fs_struct. All kthreads are
  anchored in a private SB_KERNMOUNT instance of nullfs that cannot be
  mounted on and cannot be used to follow other mounts. Userspace init
  can no longer affect kthread filesystem state and kthreads can no
  longer affect userspace fs state without explicit opting in to that.

  Path lookup from a kthread now fails by default. It makes it
  deliberately hard to offload security sensitive operations into init's
  filesystem state from a kthread.

  Places that legitimately need to look something up there opt in
  through the new scoped_with_init_fs() which temporarily overrides the
  caller's fs_struct with init's. usermodehelpers remain the only kernel
  tasks that genuinely share init's filesystem state, since they execute
  random binaries in the root filesystem (excellent...).

  The visible result is that /proc/2/root is a nullfs with an empty
  mountinfo while /proc/1/root is the real root"

* tag 'vfs-7.3-rc1.kthread' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
  initramfs_test: use test init/exit hooks to override init fs
  fs: stop rewriting paths for PF_EXITING | PF_DUMPCORE
  fs: stop rewriting kthread fs structs
  fs: start all kthreads in nullfs
  nullfs: make nullfs multi-instance
  devtmpfs: create private mount namespace
  fs: add umh argument to struct kernel_clone_args
  fs: stop sharing fs_struct between init_task and pid 1
  af_unix: use scoped_with_init_fs() for coredump socket lookup
  initramfs: use scoped_with_init_fs() for rootfs unpacking
  pnfs/blocklayout: use scoped_with_init_fs() for SCSI device lookup
  ksmbd: use scoped_with_init_fs() for VFS path operations
  ksmbd: use scoped_with_init_fs() for filesystem info path lookup
  ksmbd: use scoped_with_init_fs() for share path resolution
  fs: use scoped_with_init_fs() for kernel_read_file_from_path_initns()
  coredump: use scoped_with_init_fs() for coredump path resolution
  btrfs: use scoped_with_init_fs() for update_dev_time()
  scsi: target: use scoped_with_init_fs() for APTPL metadata
  scsi: target: use scoped_with_init_fs() for ALUA metadata
  crypto: ccp: use scoped_with_init_fs() for SEV file access
  ...
2026-08-17 11:35:12 -07:00
Julian Braha b17006b452 nohz: Replace dead select with choice default
'select' does not work on config options in a 'choice', so currently the
'select VIRT_CPU_ACCOUNTING_GEN' for NO_HZ_FULL is dead, with the choice
option VIRT_CPU_ACCOUNTING_GEN only being enabled when NO_HZ_FULL=y because
the other choice members depend on NO_HZ_FULL=n.

Remove the dead select, and encode this relationship as a default of the
choice, instead.

This dead select was found by kconfirm, a static analysis tool for Kconfig.

Signed-off-by: Julian Braha <julianbraha@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Bradley Morgan <include@grrlz.net>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/20260801160140.2391000-1-julianbraha@gmail.com
2026-08-11 15:37:23 +02:00
Tejun Heo 872a8f6b08 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next into for-7.3-arena-args
Pull bpf-next d114bb9893 ("Merge branch
'add-arena-argument-support-to-kfuncs-and-struct_ops'") to make the __arena
and __arena__nullable kfunc and struct_ops argument suffixes available. The
suffixed arguments will be used to convert sched_ext kfuncs and struct_ops
callbacks that currently pass arena pointers as scalars and rebase them by
hand.
2026-08-10 12:38:03 -10:00
Leon Hwang e474ac24a7 mm/mseal: fix mseal documentation for 32-bit kernels
mseal.o is built only for 64-bit kernels, so 32-bit kernels fall back to
sys_ni_syscall() and return -ENOSYS rather than -EPERM.

Drop architecture description in mseal.rst, since the arch feature doc has
the latest state of mseal for each architecture.

Fix the CONFIG_MSEAL_SYSTEM_MAPPINGS typo in init/Kconfig.

Link: https://lore.kernel.org/20260715131258.55499-1-leon.hwang@linux.dev
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Acked-by: Lance Yang <lance.yang@linux.dev>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Anand Moon <linux.amoon@gmail.com>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Jann Horn <jannh@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Leon Hwang <leon.hwang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:12 -07:00
Oleg Nesterov 8d75c338f0 sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL
CONFIG_SYSCTL used to make sense as a separate hidden bool before commit
61a47c1ad3 ("sysctl: Remove the sysctl system call"); it was selected
by both CONFIG_SYSCTL_SYSCALL and CONFIG_PROC_SYSCTL.

Today CONFIG_PROC_SYSCTL is the only selector, so the two are always
equal. Kill the hidden bool, rename the PROC_SYSCTL prompt to SYSCTL,
and s/CONFIG_PROC_SYSCTL/CONFIG_SYSCTL/ tree-wide.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
2026-08-05 15:28:23 +02:00
Kiryl Shutsemau (Meta) c6f11553c0 mm: decouple protnone helpers from CONFIG_NUMA_BALANCING
Patch series "userfaultfd: working set tracking for VM guest memory", v10.

This series adds userfaultfd support for tracking the working set of VM
guest memory, so a VMM can identify hot pages and reclaim cold ones to
tiered or remote storage.


This patch (of 15):

pte_protnone() and pmd_protnone() detect present-but-inaccessible page
table entries.  This capability is useful beyond NUMA balancing -- for
example, userfaultfd working set tracking uses protnone PTEs to track page
access without unmapping pages.

Introduce CONFIG_ARCH_HAS_PTE_PROTNONE to decouple the protnone PTE
infrastructure from CONFIG_NUMA_BALANCING.  The six architectures that
support protnone PTEs (x86_64, arm64, powerpc, s390, riscv, loongarch) now
select this option, and CONFIG_NUMA_BALANCING depends on it.

No functional change -- the same set of architectures continues to have
working protnone support, but the infrastructure is now available
independently of NUMA balancing.

Link: https://lore.kernel.org/20260708111417.173443-1-kirill@shutemov.name
Link: https://lore.kernel.org/20260708111417.173443-2-kirill@shutemov.name
Signed-off-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Assisted-by: Claude:claude-opus-4-6
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: James Houghton <jthoughton@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04 19:18:36 -07:00
Christian Brauner b4343aebd3 initramfs_test: use test init/exit hooks to override init fs
Most initramfs kunit tests interact with initramfs via
unpack_to_rootfs() and subsequently init_stat(), init_unlink(), etc.

It's cleaner and less error-prone to override current->fs with
userspace_init_fs for all initramfs_test_suite tests.

Link: https://patch.msgid.link/20260701-work-kunit-nullfs-v1-1-dfa60270434f@kernel.org [1]
Link: https://patch.msgid.link/20260729151320.21001-2-ddiss@suse.de # folded into [1]
Fixes: 32750c77e8 ("fs: start all kthreads in nullfs")
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/r/akOrbOsKUqgZarGw@sirena.org.uk
Signed-off-by: David Disseldorp <ddiss@suse.de>
Co-developed-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31 12:56:51 +02:00
Shivank Sharma cb6a7cc2bd initramfs: fix typo in reserve_initrd_mem comment
Fix a minor typo in the comment inside reserve_initrd_mem.
Change "virtul" to "virtual".

Signed-off-by: Shivank Sharma <shivanksharma2376543@gmail.com>
Link: https://patch.msgid.link/20260716160944.1331096-1-shivanksharma2376543@gmail.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31 10:09:11 +02:00
Thomas Gleixner dfc256dac5 calibrate: Rework delay timer calibration
The header define in asm/timex,h and the naming of the function to read the
delay timer are confusing at best.

Convert it to a config switch selected by the archictures which provide the
functionality and rename the function to delay_read_timer(), which makes
the purpose clear. Move the declaration to linux/delay.h where it belongs.

Remove the resulting empty asm/timex.h files as well.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260410120317.978403520@kernel.org
2026-07-15 15:04:55 +02:00
Thomas Weißschuh 2558084d2b futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
The robust futex unlock functionality has no relation to the generic
vDSO functionality.

Remove the dependency.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://patch.msgid.link/20260709-vdso-have_generic_vdso-v1-1-d2e1061f268b@linutronix.de
2026-07-15 10:49:02 +02:00
Tejun Heo d5b8f4cdd1 sched_ext: Track the cpu a task is runnable on
Add p->scx.runnable_cpu, the cpu @p is runnable on, or -1 when it is not.
It is stamped as @p joins the runnable_list (set_task_runnable()) and
cleared as it leaves (clr_task_runnable()), both under the rq lock.

task_cpu() can't answer "is @p on this rq" reliably: a remote wakeup changes
it under @p's pi_lock alone, without the source rq lock, so it can read as
the locked rq while @p is really elsewhere. runnable_cpu changes only under
the rq lock, so a caller holding an rq lock can compare against it to know
whether that is @p's current rq.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-13 22:18:43 -10:00
Breno Leitao 85595d3f96 init/main.c: use bootconfig_cmdline_requested() for the runtime opt-in
setup_boot_config() open-coded the same "is bootconfig requested on the
kernel command line?" check that setup_arch() performs via the shared
bootconfig_cmdline_requested() helper. Switch it to the helper so the
early (setup_arch) and late (setup_boot_config) paths use one parser and
cannot disagree on what counts as opt-in.

The helper also reports the offset of the init arguments following a "--"
separator, which is exactly what initargs_offs needs, so the local
parse_args() call, its bootconfig_params() callback and the tmp_cmdline
copy are removed.

No functional change intended.

Link: https://lore.kernel.org/all/20260626-bootconfig_using_tools-v7-9-24ab72139c29@debian.org/

Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-02 21:15:46 +09:00
Breno Leitao 378517ca3b bootconfig: skip runtime kernel.* render once prepended early
setup_boot_config() folds the embedded bootconfig "kernel" subtree into
the command line via xbc_make_cmdline("kernel"). A subsequent patch lets
an architecture prepend the build-time-rendered embedded "kernel" keys
to boot_command_line early in setup_arch(); rendering them again here
would then duplicate every key in saved_command_line and make
accumulating handlers (console=, earlycon=, ...) re-register the same
value.

Track whether the bootconfig data came from the embedded source
(from_embedded) and skip the runtime render only when the early prepend
actually happened, as reported by xbc_embedded_cmdline_applied(). On
architectures that do not select ARCH_SUPPORTS_CMDLINE_FROM_BOOTCONFIG
that helper is a stub returning false, so this path is unchanged and the
embedded "kernel" keys still reach the cmdline via the runtime parser
exactly as before.

Link: https://lore.kernel.org/all/20260626-bootconfig_using_tools-v7-8-24ab72139c29@debian.org/

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-02 21:15:46 +09:00
Breno Leitao fc9d904704 bootconfig: render embedded bootconfig as a kernel cmdline at build time
Add the build-time pipeline that renders the "kernel" subtree of
CONFIG_BOOT_CONFIG_EMBED_FILE into a flat cmdline string and stashes
it in .init.rodata as embedded_kernel_cmdline[]. A follow-up patch
adds the runtime helper that prepends this string to boot_command_line
during early architecture setup so parse_early_param() sees the values.

The build wires up:
  tools/bootconfig -C kernel - userspace tool already shared with
                               lib/bootconfig.c, used here in -C mode
                               to render a bootconfig file to a cmdline
  lib/embedded-cmdline.S     - .incbin's the rendered text plus a NUL
                               (listed under the EXTRA BOOT CONFIG
                               MAINTAINERS entry)
  lib/Makefile rule          - runs tools/bootconfig at build time
  Makefile prepare dep       - ensures tools/bootconfig is built first,
                               same pattern as tools/objtool and
                               tools/bpf/resolve_btfids

Drop the test target from tools/bootconfig/Makefile's default 'all'
recipe so that hooking the binary into the kernel build does not run
test-bootconfig.sh on every prepare. The tests stay available as
'make -C tools/bootconfig test', matching the convention of
tools/objtool and tools/bpf/resolve_btfids whose 'all' targets only
build the binary.

Require BOOT_CONFIG_EMBED_FILE to be non-empty before the new option
can be enabled, otherwise tools/bootconfig -C runs against an empty
file and prints a parse error on every kernel build.

The feature gates on CONFIG_ARCH_SUPPORTS_CMDLINE_FROM_BOOTCONFIG, a
silent symbol arches select once they've wired the prepend call into
setup_arch(). No arch selects it in this patch, so the user-visible
CONFIG_CMDLINE_FROM_BOOTCONFIG is not yet enableable; when an arch
later opts in, the runtime behavior is added by the follow-up patches.

tools/bootconfig also installs on target systems, so its own Makefile
keeps $(CC) and stays cross-buildable as a standalone tool. The kernel
build, which runs the tool on the build host during prepare, instead
forces CC=$(HOSTCC) from a dedicated tools/bootconfig rule and clears
CROSS_COMPILE= in the sub-make. Without that clear, an LLVM=1 cross
build would inherit CROSS_COMPILE and tools/scripts/Makefile.include
would inject --target=/--sysroot= flags into the host clang invocation,
producing a target binary that fails to exec ("Exec format error").

embedded-cmdline.S places the rendered string in its own .init.rodata
subsection (.init.rodata.embed_cmdline) with the "a" (allocatable,
read-only) flag and %progbits. lib/bootconfig-data.S already places
the embedded bootconfig blob in .init.rodata with the "aw" flag
(xbc_init() rewrites separators in place, so that data must be
writable). Using a distinct subsection name avoids the ld.lld section-
type mismatch that would otherwise arise from mixing "a" and "aw"
under the same name; the linker's "*(.init.rodata .init.rodata.*)"
glob still folds both into the init image and frees them after boot.

A follow-up patch wires the build-time tools/bootconfig into the
top-level clean target.

Link: https://lore.kernel.org/all/20260626-bootconfig_using_tools-v7-3-24ab72139c29@debian.org/

Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-02 21:15:45 +09:00
Miguel Ojeda 608045a91d rust: allow suspicious_runtime_symbol_definitions lint for Rust >= 1.98
Starting with Rust 1.98.0 (expected 2026-08-20), Rust is introducing a
couple new lints, `invalid_runtime_symbol_definitions` (deny-by-default)
and `suspicious_runtime_symbol_definitions` (warn-by-default), which check
the signature of items whose symbol name is a runtime symbol expected by
`core`.

Our build hits the second one, i.e. the warning:

    error: suspicious definition of the runtime `strlen` symbol used by the standard library
         --> rust/bindings/bindings_generated.rs:20018:5
          |
    20018 |     pub fn strlen(s: *const ffi::c_char) -> usize;
          |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
          |
          = note: expected `unsafe extern "C" fn(*const i8) -> usize`
                  found    `unsafe extern "C" fn(*const u8) -> usize`
          = help: either fix the signature or remove any attributes like `#[unsafe(no_mangle)]`, `#[unsafe(export_name = "strlen")]`, or `#[link_name = "strlen"]`
          = help: allow this lint if the signature is compatible
          = note: `-D suspicious-runtime-symbol-definitions` implied by `-D warnings`
          = help: to override `-D warnings` add `#[allow(suspicious_runtime_symbol_definitions)]`

    error: suspicious definition of the runtime `strlen` symbol used by the standard library
         --> rust/uapi/uapi_generated.rs:14236:5
          |
    14236 |     pub fn strlen(s: *const ffi::c_char) -> usize;
          |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
          |
          = note: expected `unsafe extern "C" fn(*const i8) -> usize`
                  found    `unsafe extern "C" fn(*const u8) -> usize`
          = help: either fix the signature or remove any attributes like `#[unsafe(no_mangle)]`, `#[unsafe(export_name = "strlen")]`, or `#[link_name = "strlen"]`
          = help: allow this lint if the signature is compatible
          = note: `-D suspicious-runtime-symbol-definitions` implied by `-D warnings`
          = help: to override `-D warnings` add `#[allow(suspicious_runtime_symbol_definitions)]`

Thus `allow` the lint in `bindings` and `uapi`.

A more targeted alternative to avoid `allow`ing it would be to pass
`--blocklist-function strlen` to `bindgen`, but we would perhaps need
to adjust if other C headers end up adding more (or Rust checking more).
Since it is just the less critical one that we hit, and since eventually
this should be properly fixed by getting upstream Rust to provide a flag
like GCC/Clang's `-funsigned-char` [2][3], just `allow` it for now.

Cc: Urgau <urgau@numericable.fr>
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/155521 [1]
Link: https://github.com/rust-lang/rust/issues/138446 [2]
Link: https://github.com/Rust-for-Linux/linux/issues/355 [3]
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Link: https://patch.msgid.link/20260615143225.471756-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2026-06-29 13:02:15 +02:00
Christian Brauner 14adbd5341 fs: stop sharing fs_struct between init_task and pid 1
Spawn kernel_init (PID 1) via kernel_clone() directly instead of
user_mode_thread(), without CLONE_FS. This gives PID 1 its own private
copy of init_task's fs_struct rather than sharing it.

This is a prerequisite for isolating kthreads in nullfs: when
init_task's fs is later pointed at nullfs, PID 1 must not share it
or init_userspace_fs() would modify init_task's fs as well, defeating
the isolation.

At this stage PID 1 still gets rootfs (a private copy rather than a
shared reference), so there is no functional change.

Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-19-77ee053060e0@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29 10:53:32 +02:00
Christian Brauner d0f102fce3 initramfs: use scoped_with_init_fs() for rootfs unpacking
Extract the initramfs unpacking code into a separate
unpack_initramfs() function and wrap its invocation from
do_populate_rootfs() with scoped_with_init_fs(). This ensures all
file operations during initramfs unpacking (including filp_open()
calls in do_name() and populate_initrd_image()) happen in init's
filesystem context.

Note that security_initramfs_populated() needs the scope as well since
it does use current->fs to derive the initramfs superblock.

do_populate_rootfs() ← async_schedule_domain() ← kworker (async
workqueue)

May also run synchronously from PID 1 in case async workqueue is
considered full. Overriding in that case is fine as well.

Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-17-77ee053060e0@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29 10:53:31 +02:00
Christian Brauner 9a8e296958 fs: make userspace_init_fs a dynamically-initialized pointer
Change userspace_init_fs from a declared-but-unused extern struct to
a dynamically initialized pointer. Add init_userspace_fs() which is
called early in kernel_init() (PID 1) to record PID 1's fs_struct
as the canonical userspace filesystem state.

Wire up __override_init_fs() and __revert_init_fs() to actually swap
current->fs to/from userspace_init_fs. Previously these were no-ops
that stored current->fs back to itself.

Fix nullfs_userspace_init() to compare against userspace_init_fs
instead of &init_fs. When PID 1 unshares its filesystem state, revert
userspace_init_fs to init_fs's root (nullfs) so that stale filesystem
state is not silently inherited by kworkers and usermodehelpers.

At this stage PID 1's fs still points to rootfs (set by
init_mount_tree), so userspace_init_fs points to rootfs and
scoped_with_init_fs() is functionally equivalent to its previous no-op
behavior.

Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-5-77ee053060e0@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29 10:44:05 +02:00
Christian Brauner 1d4ee94a51 fs: add real_fs to track task's actual fs_struct
Add a real_fs field to task_struct that always mirrors the fs field.
This lays the groundwork for distinguishing between a task's permanent
fs_struct and one that is temporarily overridden via scoped_with_init_fs().

When a kthread temporarily overrides current->fs for path lookup, we
need to know the original fs_struct for operations like exit_fs() and
unshare_fs_struct() that must operate on the real, permanent fs.

For now real_fs is always equal to fs. It is maintained alongside fs in
all the relevant paths: exit_fs(), unshare_fs_struct(),
switch_fs_struct(), and copy_fs().

Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-4-77ee053060e0@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29 10:43:45 +02:00