linux/init/Kconfig, branch v6.17

kbuild: Disable CC_HAS_ASM_GOTO_OUTPUT on clang < 17

2025-09-24T07:29:15Z

clang < 17 fails to use scope local labels with CONFIG_CC_HAS_ASM_GOTO_OUTPUT=y: { __label__ local_lbl; ... unsafe_get_user(uval, uaddr, local_lbl); ... return 0; local_lbl: return -EFAULT; } when two such scopes exist in the same function: error: cannot jump from this asm goto statement to one of its possible targets There are other failure scenarios. Shuffling code around slightly makes it worse and fail even with one instance. That issue prevents using local labels for a cleanup based user access mechanism. After failed attempts to provide a simple enough test case for the 'depends on' test in Kconfig, the initial cure was to mark ASM goto broken on clang versions < 17 to get this road block out of the way. But Nathan pointed out that this is a known clang issue and indeed affects clang < version 17 in combination with cleanup(). It's not even required to use local labels for that. The clang issue tracker has a small enough test case, which can be used as a test in the 'depends on' section of CC_HAS_ASM_GOTO_OUTPUT: void bar(void **); void* baz(void); int foo (void) { { asm goto("jmp %l0"::::l0); return 0; l0: return 1; } void *x __attribute__((cleanup(bar))) = baz(); { asm goto("jmp %l0"::::l1); return 42; l1: return 0xff; } } Add another dependency to config CC_HAS_ASM_GOTO_OUTPUT for it and use the clang issue tracker test case for detection by condensing it to obfuscated C-code contest format. This reliably catches the problem on clang < 17 and did not show any issues on the non broken GCC versions. That test might be sufficient to catch all issues and therefore could replace the existing test, but keeping that around does no harm either. Thanks to Nathan for pointing to the relevant clang issue! Suggested-by: Nathan Chancellor Signed-off-by: Thomas Gleixner Cc: Nathan Chancellor Reviewed-by: Nathan Chancellor Link: https://github.com/ClangBuiltLinux/linux/issues/1886 Link: https://github.com/llvm/llvm-project/commit/f023f5cdb2e6c19026f04a15b5a935c041835d14

Merge tag 'rust-fixes-6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

2025-09-06T19:33:09Z

Pull rust fixes from Miguel Ojeda: - Two changes to prepare for the future Rust 1.91.0 release (expected 2025-10-30, currently in nightly): a target specification format change and a renamed, soon-to-be-stabilized 'core' function. * tag 'rust-fixes-6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: rust: support Rust >= 1.91.0 target spec rust: use the new name Location::file_as_c_str() in Rust >= 1.91.0

rust: use the new name Location::file_as_c_str() in Rust >= 1.91.0

2025-08-31T21:34:34Z

As part of the stabilization of Location::file_with_nul(), it was brought up that the with_nul() suffix usually means something else in Rust APIs, so the API is being renamed prior to stabilization [1]. Thus, use the new name on new rustc versions. Link: https://www.github.com/rust-lang/rust/pull/145928 [1] Signed-off-by: Alice Ryhl Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/20250827-file_as_c_str-v1-1-d3f5a3916a9c@google.com [ Kept `cfg` separation. Reworded slightly. - Miguel ] Signed-off-by: Miguel Ojeda

hardening: Require clang 20.1.0 for __counted_by

2025-08-29T19:04:53Z

After an innocuous change in -next that modified a structure that contains __counted_by, clang-19 start crashing when building certain files in drivers/gpu/drm/xe. When assertions are enabled, the more descriptive failure is: clang: clang/lib/AST/RecordLayoutBuilder.cpp:3335: const ASTRecordLayout &clang::ASTContext::getASTRecordLayout(const RecordDecl *) const: Assertion `D && "Cannot get layout of forward declarations!"' failed. According to a reverse bisect, a tangential change to the LLVM IR generation phase of clang during the LLVM 20 development cycle [1] resolves this problem. Bump the version of clang that enables CONFIG_CC_HAS_COUNTED_BY to 20.1.0 to ensure that this issue cannot be hit. Link: https://github.com/llvm/llvm-project/commit/160fb1121cdf703c3ef5e61fb26c5659eb581489 [1] Signed-off-by: Nathan Chancellor Reviewed-by: Justin Stitt Link: https://lore.kernel.org/r/20250807-fix-counted_by-clang-19-v1-1-902c86c1d515@kernel.org Signed-off-by: Kees Cook

Merge tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-08-03T23:23:09Z

Pull non-MM updates from Andrew Morton: "Significant patch series in this pull request: - "squashfs: Remove page->mapping references" (Matthew Wilcox) gets us closer to being able to remove page->mapping - "relayfs: misc changes" (Jason Xing) does some maintenance and minor feature addition work in relayfs - "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches us from static preallocation of the kdump crashkernel's working memory over to dynamic allocation. So the difficulty of a-priori estimation of the second kernel's needs is removed and the first kernel obtains extra memory - "generalize panic_print's dump function to be used by other kernel parts" (Feng Tang) implements some consolidation and rationalization of the various ways in which a failing kernel splats information at the operator * tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits) tools/getdelays: add backward compatibility for taskstats version kho: add test for kexec handover delaytop: enhance error logging and add PSI feature description samples: Kconfig: fix spelling mistake "instancess" -> "instances" fat: fix too many log in fat_chain_add() scripts/spelling.txt: add notifer||notifier to spelling.txt xen/xenbus: fix typo "notifer" net: mvneta: fix typo "notifer" drm/xe: fix typo "notifer" cxl: mce: fix typo "notifer" KVM: x86: fix typo "notifer" MAINTAINERS: add maintainers for delaytop ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below() ucount: fix atomic_long_inc_below() argument type kexec: enable CMA based contiguous allocation stackdepot: make max number of pools boot-time configurable lib/xxhash: remove unused functions init/Kconfig: restore CONFIG_BROKEN help text lib/raid6: update recov_rvv.c zero page usage docs: update docs after introducing delaytop ...

init/Kconfig: restore CONFIG_BROKEN help text

2025-08-02T19:01:37Z

Linus added it in 2003, it later was removed. Put it back. Cc: Anshuman Khandual Cc: Borislav Betkov Cc: David S. Miller Cc: Ingo Molnar Cc: Thomas Gleinxer Cc: Christophe Leroy Signed-off-by: Andrew Morton

Merge tag 'sched_ext-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

2025-07-31T23:29:46Z

Pull sched_ext updates from Tejun Heo: - Add support for cgroup "cpu.max" interface - Code organization cleanup so that ext_idle.c doesn't depend on the source-file-inclusion build method of sched/ - Drop UP paths in accordance with sched core changes - Documentation and other misc changes * tag 'sched_ext-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: sched_ext: Fix scx_bpf_reenqueue_local() reference sched_ext: Drop kfuncs marked for removal in 6.15 sched_ext, rcu: Eject BPF scheduler on RCU CPU stall panic kernel/sched/ext.c: fix typo "occured" -> "occurred" in comments sched_ext: Add support for cgroup bandwidth control interface sched_ext, sched/core: Factor out struct scx_task_group sched_ext: Return NULL in llc_span sched_ext: Always use SMP versions in kernel/sched/ext_idle.h sched_ext: Always use SMP versions in kernel/sched/ext_idle.c sched_ext: Always use SMP versions in kernel/sched/ext.h sched_ext: Always use SMP versions in kernel/sched/ext.c sched_ext: Documentation: Clarify time slice handling in task lifecycle sched_ext: Make scx_locked_rq() inline sched_ext: Make scx_rq_bypassing() inline sched_ext: idle: Make local functions static in ext_idle.c sched_ext: idle: Remove unnecessary ifdef in scx_bpf_cpu_node()

Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-07-31T21:57:54Z

Pull MM updates from Andrew Morton: "As usual, many cleanups. The below blurbiage describes 42 patchsets. 21 of those are partially or fully cleanup work. "cleans up", "cleanup", "maintainability", "rationalizes", etc. I never knew the MM code was so dirty. "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes) addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for merging with existing adjacent VMAs. "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park) adds a new kernel module which simplifies the setup and usage of DAMON in production environments. "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig) is a cleanup to the writeback code which removes a couple of pointers from struct writeback_control. "drivers/base/node.c: optimization and cleanups" (Donet Tom) contains largely uncorrelated cleanups to the NUMA node setup and management code. "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman) does some maintenance work on the userfaultfd code. "Readahead tweaks for larger folios" (Ryan Roberts) implements some tuneups for pagecache readahead when it is reading into order>0 folios. "selftests/mm: Tweaks to the cow test" (Mark Brown) provides some cleanups and consistency improvements to the selftests code. "Optimize mremap() for large folios" (Dev Jain) does that. A 37% reduction in execution time was measured in a memset+mremap+munmap microbenchmark. "Remove zero_user()" (Matthew Wilcox) expunges zero_user() in favor of the more modern memzero_page(). "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand) addresses some warts which David noticed in the huge page code. These were not known to be causing any issues at this time. "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park) provides some cleanup and consolidation work in DAMON. "use vm_flags_t consistently" (Lorenzo Stoakes) uses vm_flags_t in places where we were inappropriately using other types. "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy) increases the reliability of large page allocation in the memfd code. "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple) removes several now-unneeded PFN_* flags. "mm/damon: decouple sysfs from core" (SeongJae Park) implememnts some cleanup and maintainability work in the DAMON sysfs layer. "madvise cleanup" (Lorenzo Stoakes) does quite a lot of cleanup/maintenance work in the madvise() code. "madvise anon_name cleanups" (Vlastimil Babka) provides additional cleanups on top or Lorenzo's effort. "Implement numa node notifier" (Oscar Salvador) creates a standalone notifier for NUMA node memory state changes. Previously these were lumped under the more general memory on/offline notifier. "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan) cleans up the pageblock isolation code and fixes a potential issue which doesn't seem to cause any problems in practice. "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park) adds additional drgn- and python-based DAMON selftests which are more comprehensive than the existing selftest suite. "Misc rework on hugetlb faulting path" (Oscar Salvador) fixes a rather obscure deadlock in the hugetlb fault code and follows that fix with a series of cleanups. "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport) rationalizes and cleans up the highmem-specific code in the CMA allocator. "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand) provides cleanups and future-preparedness to the migration code. "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park) adds some tracepoints to some DAMON auto-tuning code. "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park) does that. "mm/damon: misc cleanups" (SeongJae Park) also does what it claims. "mm: folio_pte_batch() improvements" (David Hildenbrand) cleans up the large folio PTE batching code. "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park) facilitates dynamic alteration of DAMON's inter-node allocation policy. "Remove unmap_and_put_page()" (Vishal Moola) provides a couple of page->folio conversions. "mm: per-node proactive reclaim" (Davidlohr Bueso) implements a per-node control of proactive reclaim - beyond the current memcg-based implementation. "mm/damon: remove damon_callback" (SeongJae Park) replaces the damon_callback interface with a more general and powerful damon_call()+damos_walk() interface. "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes) implements a number of mremap cleanups (of course) in preparation for adding new mremap() functionality: newly permit the remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It still excludes some specialized situations where this cannot be performed reliably. "drop hugetlb_free_pgd_range()" (Anthony Yznaga) switches some sparc hugetlb code over to the generic version and removes the thus-unneeded hugetlb_free_pgd_range(). "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park) augments the present userspace-requested update of DAMON sysfs monitoring files. Automatic update is now provided, along with a tunable to control the update interval. "Some randome fixes and cleanups to swapfile" (Kemeng Shi) does what is claims. "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand) provides (and uses) a means by which debug-style functions can grab a copy of a pageframe and inspect it locklessly without tripping over the races inherent in operating on the live pageframe directly. "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan) addresses the large contention issues which can be triggered by reads from that procfs file. Latencies are reduced by more than half in some situations. The series also introduces several new selftests for the /proc/pid/maps interface. "__folio_split() clean up" (Zi Yan) cleans up __folio_split()! "Optimize mprotect() for large folios" (Dev Jain) provides some quite large (>3x) speedups to mprotect() when dealing with large folios. "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian) does some cleanup work in the selftests code. "tools/testing: expand mremap testing" (Lorenzo Stoakes) extends the mremap() selftest in several ways, including adding more checking of Lorenzo's recently added "permit mremap() move of multiple VMAs" feature. "selftests/damon/sysfs.py: test all parameters" (SeongJae Park) extends the DAMON sysfs interface selftest so that it tests all possible user-requested parameters. Rather than the present minimal subset" * tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits) MAINTAINERS: add missing headers to mempory policy & migration section MAINTAINERS: add missing file to cgroup section MAINTAINERS: add MM MISC section, add missing files to MISC and CORE MAINTAINERS: add missing zsmalloc file MAINTAINERS: add missing files to page alloc section MAINTAINERS: add missing shrinker files MAINTAINERS: move memremap.[ch] to hotplug section MAINTAINERS: add missing mm_slot.h file THP section MAINTAINERS: add missing interval_tree.c to memory mapping section MAINTAINERS: add missing percpu-internal.h file to per-cpu section mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info() selftests/damon: introduce _common.sh to host shared function selftests/damon/sysfs.py: test runtime reduction of DAMON parameters selftests/damon/sysfs.py: test non-default parameters runtime commit selftests/damon/sysfs.py: generalize DAMON context commit assertion selftests/damon/sysfs.py: generalize monitoring attributes commit assertion selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion selftests/damon/sysfs.py: test DAMOS filters commitment selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion selftests/damon/sysfs.py: test DAMOS destinations commitment ...

Merge tag 'sched-core-2025-07-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-07-30T00:42:52Z

Pull scheduler updates from Ingo Molnar: "Core scheduler changes: - Better tracking of maximum lag of tasks in presence of different slices duration, for better handling of lag in the fair scheduler (Vincent Guittot) - Clean up and standardize #if/#else/#endif markers throughout the entire scheduler code base (Ingo Molnar) - Make SMP unconditional: build the SMP scheduler's data structures and logic on UP kernel too, even though they are not used, to simplify the scheduler and remove around 200 #ifdef/[#else]/#endif blocks from the scheduler (Ingo Molnar) - Reorganize cgroup bandwidth control interface handling for better interfacing with sched_ext (Tejun Heo) Balancing: - Bump sd->max_newidle_lb_cost when newidle balance fails (Chris Mason) - Remove sched_domain_topology_level::flags to simplify the code (Prateek Nayak) - Simplify and clean up build_sched_topology() (Li Chen) - Optimize build_sched_topology() on large machines (Li Chen) Real-time scheduling: - Add initial version of proxy execution: a mechanism for mutex-owning tasks to inherit the scheduling context of higher priority waiters. Currently limited to a single runqueue and conditional on CONFIG_EXPERT, and other limitations (John Stultz, Peter Zijlstra, Valentin Schneider) - Deadline scheduler (Juri Lelli): - Fix dl_servers initialization order (Juri Lelli) - Fix DL scheduler's root domain reinitialization logic (Juri Lelli) - Fix accounting bugs after global limits change (Juri Lelli) - Fix scalability regression by implementing less agressive dl_server handling (Peter Zijlstra) PSI: - Improve scalability by optimizing psi_group_change() cpu_clock() usage (Peter Zijlstra) Rust changes: - Make Task, CondVar and PollCondVar methods inline to avoid unnecessary function calls (Kunwu Chan, Panagiotis Foliadis) - Add might_sleep() support for Rust code: Rust's "#[track_caller]" mechanism is used so that Rust's might_sleep() doesn't need to be defined as a macro (Fujita Tomonori) - Introduce file_from_location() (Boqun Feng) Debugging & instrumentation: - Make clangd usable with scheduler source code files again (Peter Zijlstra) - tools: Add root_domains_dump.py which dumps root domains info (Juri Lelli) - tools: Add dl_bw_dump.py for printing bandwidth accounting info (Juri Lelli) Misc cleanups & fixes: - Remove play_idle() (Feng Lee) - Fix check_preemption_disabled() (Sebastian Andrzej Siewior) - Do not call __put_task_struct() on RT if pi_blocked_on is set (Luis Claudio R. Goncalves) - Correct the comment in place_entity() (wang wei)" * tag 'sched-core-2025-07-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (84 commits) sched/idle: Remove play_idle() sched: Do not call __put_task_struct() on rt if pi_blocked_on is set sched: Start blocked_on chain processing in find_proxy_task() sched: Fix proxy/current (push,pull)ability sched: Add an initial sketch of the find_proxy_task() function sched: Fix runtime accounting w/ split exec & sched contexts sched: Move update_curr_task logic into update_curr_se locking/mutex: Add p->blocked_on wrappers for correctness checks locking/mutex: Rework task_struct::blocked_on sched: Add CONFIG_SCHED_PROXY_EXEC & boot argument to enable/disable sched/topology: Remove sched_domain_topology_level::flags x86/smpboot: avoid SMT domain attach/destroy if SMT is not enabled x86/smpboot: moves x86_topology to static initialize and truncate x86/smpboot: remove redundant CONFIG_SCHED_SMT smpboot: introduce SDTL_INIT() helper to tidy sched topology setup tools/sched: Add dl_bw_dump.py for printing bandwidth accounting info tools/sched: Add root_domains_dump.py which dumps root domains info sched/deadline: Fix accounting after global limits change sched/deadline: Reset extra_bw to max_bw when clearing root domains sched/deadline: Initialize dl_servers after SMP ...

Merge tag 'locking-futex-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-07-29T21:39:42Z

Pull futex updates from Thomas Gleixner: - Switch the reference counting to a RCU based per-CPU reference to address a performance bottleneck vs the single instance rcuref variant - Make the futex selftest build on 32-bit architectures which only support 64-bit time_t, e.g. RISCV-32 - Cleanups and improvements in selftests and futex bench * tag 'locking-futex-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests/futex: Fix spelling mistake "Succeffuly" -> "Successfully" selftests/futex: Define SYS_futex on 32-bit architectures with 64-bit time_t perf bench futex: Remove support for IMMUTABLE selftests/futex: Remove support for IMMUTABLE futex: Remove support for IMMUTABLE futex: Make futex_private_hash_get() static futex: Use RCU-based per-CPU reference counting instead of rcuref_t selftests/futex: Adapt the private hash test to RCU related changes