Changes in Kbuild

5d0d3623303775d750e122a2542d1a26c8573d38 - Merge tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

Tue, 14 Apr 2026 16:18:40 +0000

Merge tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linuxPull Kbuild/Kconfig updates from Nicolas Schier: "Kbuild: - reject unexpected values for LLVM= - uapi: remove usage of toolchain headers - switch from '-fms-extensions' to '-fms-anonymous-structs' when available (currently: clang >= 23.0.0) - reduce the number of compiler-generated suffixes for clang thin-lto build - reduce output spam ("GEN Makefile") when building out of tree - improve portability for testing headers - also test UAPI headers against C++ compilers - drop build ID architecture allow-list in vdso_install - only run checksyscalls when necessary - update the debug information notes in reproducible-builds.rst - expand inlining hints with -fdiagnostics-show-inlining-chain Kconfig: - forbid multiple entries with the same symbol in a choice - error out on duplicated kconfig inclusion"* tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (35 commits) kbuild: expand inlining hints with -fdiagnostics-show-inlining-chain kconfig: forbid multiple entries with the same symbol in a choice Documentation: kbuild: Update the debug information notes in reproducible-builds.rst checksyscalls: move instance functionality into generic code checksyscalls: only run when necessary checksyscalls: fail on all intermediate errors checksyscalls: move path to reference table to a variable kbuild: vdso_install: drop build ID architecture allow-list kbuild: vdso_install: gracefully handle images without build ID kbuild: vdso_install: hide readelf warnings kbuild: vdso_install: split out the readelf invocation kbuild: uapi: also test UAPI headers against C++ compilers kbuild: uapi: provide a C++ compatible dummy definition of NULL kbuild: uapi: handle UML in architecture-specific exclusion lists kbuild: uapi: move all include path flags together kbuild: uapi: move some compiler arguments out of the command definition check-uapi: use dummy libc includes check-uapi: honor ${CROSS_COMPILE} setting check-uapi: link into shared objects kbuild: reduce output spam when building out of tree ... List of files: /linux/Kbuild

c7c55f0e1667aa25c0ac047bd873159722358f6c - checksyscalls: move instance functionality into generic code

Thu, 02 Apr 2026 14:36:20 +0000

checksyscalls: move instance functionality into generic codeOn MIPS the checksyscalls.sh script may be executed multiple times.Currently these multiple executions are executed on each build as kbuildsee that the commands have changed each time.Use a dedicated stamp file for each different invocation to avoid thespurious executions.Signed-off-by: Thomas Weißschuh Acked-by: Arnd Bergmann Reviewed-by: Nicolas Schier Link: https://patch.msgid.link/20260402-kbuild-missing-syscalls-v3-3-6641be1de2db@weissschuh.netSigned-off-by: Nicolas Schier List of files: /linux/Kbuild

b34db3fa85c4d34ceee5231cd27e587153bc25ab - checksyscalls: only run when necessary

Thu, 02 Apr 2026 14:36:19 +0000

checksyscalls: only run when necessaryCurrently checksyscalls.sh is unconditionally executed during each build.Most of these executions are unnecessary.Only run checksyscalls.sh if one of its inputs have changed.This new logic does not work for the multiple invocations done for MIPS.The effect is that checksyscalls.sh is still executed unconditionally.However this is not worse than before.Signed-off-by: Thomas Weißschuh Acked-by: Arnd Bergmann Reviewed-by: Nicolas Schier Link: https://patch.msgid.link/20260402-kbuild-missing-syscalls-v3-2-6641be1de2db@weissschuh.netSigned-off-by: Nicolas Schier List of files: /linux/Kbuild

a4a508df2aa34f8650afde54ea804321c618f45f - Merge tag 'v6.18' into next

Sat, 13 Dec 2025 09:18:20 +0000

Merge tag 'v6.18' into nextSync up with the mainline to bring in the latest APIs. List of files: /linux/Kbuild

2ace52718376fdb56aca863da2eebe70d7e2ddb1 - Merge branch 'objtool/core'

Fri, 21 Nov 2025 10:21:20 +0000

Merge branch 'objtool/core'Bring in the UDB and objtool data annotations to avoid conflicts while further extending the bug exceptions.Signed-off-by: Peter Zijlstra List of files: /linux/Kbuild

f39b6c468c52745dbca9a842d91c8373fda208ab - Merge tag 'v6.18-rc6' into for-linus

Tue, 18 Nov 2025 07:16:55 +0000

Merge tag 'v6.18-rc6' into for-linusSync up with the mainline to bring in definition ofINPUT_PROP_HAPTIC_TOUCHPAD. List of files: /linux/Kbuild

cb9f145f638d7afa633632a9290d6ad06caeb8ee - Merge remote-tracking branch 'drm/drm-next' into msm-next-robclark

Sat, 01 Nov 2025 12:47:30 +0000

Merge remote-tracking branch 'drm/drm-next' into msm-next-robclarkBack-merge drm-next to get caught up.Signed-off-by: Rob Clark List of files: /linux/Kbuild

ec2e0fb07d789976c601bec19ecced7a501c3705 - Merge tag 'asoc-fix-v6.18-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

Thu, 16 Oct 2025 18:14:24 +0000

Merge tag 'asoc-fix-v6.18-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linusASoC: Fixes for v6.18A moderately large collection of driver specific fixes, plus a few newquirks and device IDs. The NAU8821 changes are a little large but morein mechanical ways than in ways that are complex. List of files: /linux/Kbuild

82ee50252dc891e3f3b32d923bb4f656d300b772 - Merge drm/drm-next into drm-xe-next

Tue, 14 Oct 2025 09:31:49 +0000

Merge drm/drm-next into drm-xe-nextBackmerging to bring in 6.18-rc1.Signed-off-by: Thomas Hellström List of files: /linux/Kbuild

48a710760e10a4f36e11233a21860796ba204b1e - Merge drm/drm-fixes into drm-misc-fixes

Tue, 14 Oct 2025 08:59:58 +0000

Merge drm/drm-fixes into drm-misc-fixesUpdating drm-misc-fixes to the state of v6.18-rc1.Signed-off-by: Thomas Zimmermann List of files: /linux/Kbuild

2acee98fcc61052d63fab4539fcb6ee677555645 - Merge drm/drm-next into drm-intel-next

Tue, 14 Oct 2025 07:37:11 +0000

Merge drm/drm-next into drm-intel-nextSync to v6.18-rc1.Signed-off-by: Jani Nikula List of files: /linux/Kbuild

4f38da1f027ea2c9f01bb71daa7a299c191b6940 - spi: Merge up v6.18-rc1

Mon, 13 Oct 2025 12:32:13 +0000

spi: Merge up v6.18-rc1Ensure my CI has a sensible baseline. List of files: /linux/Kbuild

9b966ae42235a88eaea714be09ff3d698535bdfe - Merge drm/drm-next into drm-misc-next

Mon, 13 Oct 2025 07:19:19 +0000

Merge drm/drm-next into drm-misc-nextUpdating drm-misc-next to the state of v6.18-rc1.Signed-off-by: Thomas Zimmermann List of files: /linux/Kbuild

6c7340a7a8d2b6ecad1ad108f6daa73ba1dc082f - Merge tag 'sched-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Tue, 30 Sep 2025 17:35:11 +0000

Merge tag 'sched-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipPull scheduler updates from Ingo Molnar: "Core scheduler changes: - Make migrate_{en,dis}able() inline, to improve performance (Menglong Dong) - Move STDL_INIT() functions out-of-line (Peter Zijlstra) - Unify the SCHED_{SMT,CLUSTER,MC} Kconfig (Peter Zijlstra) Fair scheduling: - Defer throttling to when tasks exit to user-space, to reduce the chance & impact of throttle-preemption with held locks and other resources (Aaron Lu, Valentin Schneider) - Get rid of sched_domains_curr_level hack for tl->cpumask(), as the warning was getting triggered on certain topologies (Peter Zijlstra) Misc cleanups & fixes: - Header cleanups (Menglong Dong) - Fix race in push_dl_task() (Harshit Agarwal)"* tag 'sched-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Fix some typos in include/linux/preempt.h sched: Make migrate_{en,dis}able() inline rcu: Replace preempt.h with sched.h in include/linux/rcupdate.h arch: Add the macro COMPILE_OFFSETS to all the asm-offsets.c sched/fair: Do not balance task to a throttled cfs_rq sched/fair: Do not special case tasks in throttled hierarchy sched/fair: update_cfs_group() for throttled cfs_rqs sched/fair: Propagate load for throttled cfs_rq sched/fair: Get rid of throttled_lb_pair() sched/fair: Task based throttle time accounting sched/fair: Switch to task based throttle model sched/fair: Implement throttle task work and related helpers sched/fair: Add related data structure for task based throttle sched: Unify the SCHED_{SMT,CLUSTER,MC} Kconfig sched: Move STDL_INIT() functions out-of-line sched/fair: Get rid of sched_domains_curr_level hack for tl->cpumask() sched/deadline: Fix race in push_dl_task() List of files: /linux/Kbuild

378b7708194fff77c9020392067329931c3fcc04 - sched: Make migrate_{en,dis}able() inline

Wed, 17 Sep 2025 06:09:15 +0000

sched: Make migrate_{en,dis}able() inlineFor now, migrate_enable and migrate_disable are global, which makes thembecome hotspots in some case. Take BPF for example, the function callingto migrate_enable and migrate_disable in BPF trampoline can introducesignificant overhead, and following is the 'perf top' of FENTRY'sbenchmark (./tools/testing/selftests/bpf/bench trig-fentry): 54.63% bpf_prog_2dcccf652aac1793_bench_trigger_fentry [k] bpf_prog_2dcccf652aac1793_bench_trigger_fentry 10.43% [kernel] [k] migrate_enable 10.07% bpf_trampoline_6442517037 [k] bpf_trampoline_6442517037 8.06% [kernel] [k] __bpf_prog_exit_recur 4.11% libc.so.6 [.] syscall 2.15% [kernel] [k] entry_SYSCALL_64 1.48% [kernel] [k] memchr_inv 1.32% [kernel] [k] fput 1.16% [kernel] [k] _copy_to_user 0.73% [kernel] [k] bpf_prog_test_run_raw_tpSo in this commit, we make migrate_enable/migrate_disable inline to obtainbetter performance. The struct rq is defined internally inkernel/sched/sched.h, and the field "nr_pinned" is accessed inmigrate_enable/migrate_disable, which makes it hard to make them inline.Alexei Starovoitov suggests to generate the offset of "nr_pinned" in [1],so we can define the migrate_enable/migrate_disable ininclude/linux/sched.h and access "this_rq()->nr_pinned" with"(void *)this_rq() + RQ_nr_pinned".The offset of "nr_pinned" is generated in include/generated/rq-offsets.hby kernel/sched/rq-offsets.c.Generally speaking, we move the definition of migrate_enable andmigrate_disable to include/linux/sched.h from kernel/sched/core.c. Thecalling to __set_cpus_allowed_ptr() is leaved in ___migrate_enable().The "struct rq" is not available in include/linux/sched.h, so we can'taccess the "runqueues" with this_cpu_ptr(), as the compilation will failin this_cpu_ptr() -> raw_cpu_ptr() -> __verify_pcpu_ptr(): typeof((ptr) + 0)So we introduce the this_rq_raw() and access the runqueues witharch_raw_cpu_ptr/PERCPU_PTR directly.The variable "runqueues" is not visible in the kernel modules, and exportit is not a good idea. As Peter Zijlstra advised in [2], we define andexport migrate_enable/migrate_disable in kernel/sched/core.c too, and usethem for the modules.Before this patch, the performance of BPF FENTRY is: fentry : 113.030 ± 0.149M/s fentry : 112.501 ± 0.187M/s fentry : 112.828 ± 0.267M/s fentry : 115.287 ± 0.241M/sAfter this patch, the performance of BPF FENTRY increases to: fentry : 143.644 ± 0.670M/s fentry : 149.764 ± 0.362M/s fentry : 149.642 ± 0.156M/s fentry : 145.263 ± 0.221M/sSigned-off-by: Menglong Dong Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/bpf/CAADnVQ+5sEDKHdsJY5ZsfGDO_1SEhhQWHrt2SMBG5SYyQ+jt7w@mail.gmail.com/ [1]Link: https://lore.kernel.org/all/20250819123214.GH4067720@noisy.programming.kicks-ass.net/ [2] List of files: /linux/Kbuild

4f9786035f9e519db41375818e1d0b5f20da2f10 - Merge branch 'next' into for-linus

Mon, 02 Jun 2025 04:41:07 +0000

Merge branch 'next' into for-linusPrepare input updates for 6.16 merge window. List of files: /linux/Kbuild

bbfd5594756011167b8f8de9a00e0c946afda1e6 - Merge drm/drm-next into drm-intel-gt-next

Wed, 28 May 2025 07:20:17 +0000

Merge drm/drm-next into drm-intel-gt-nextNeed to pull in a67221b5eb8d ("drm/i915/dp: Return min bpc supported by source instead of 0")in order to fix build breakage on GCC 9.4.0 (from Ubuntu 20.04).Signed-off-by: Joonas Lahtinen List of files: /linux/Kbuild

d51b9d81f7883f526b26e3ab903e646274aebeb1 - Merge tag 'v6.15-rc6' into next

Thu, 15 May 2025 23:20:39 +0000

Merge tag 'v6.15-rc6' into nextSync up with mainline to bring in xpad controller changes. List of files: /linux/Kbuild

9f13acb2406a3aed90c6738b3a2f1c0e43118cbd - Merge tag 'v6.15-rc1' into x86/cpu, to refresh the branch with upstream changes

Fri, 11 Apr 2025 09:13:27 +0000

Merge tag 'v6.15-rc1' into x86/cpu, to refresh the branch with upstream changesSigned-off-by: Ingo Molnar List of files: /linux/Kbuild

6ce0fdaae043803bb324d915ce0fe43316bf1e81 - Merge tag 'v6.15-rc1' into x86/asm, to refresh the branch

Wed, 09 Apr 2025 19:39:43 +0000

Merge tag 'v6.15-rc1' into x86/asm, to refresh the branchSigned-off-by: Ingo Molnar List of files: /linux/Kbuild