kernel/linux.git/Documentation/features, branch master

Merge tag 'alpha-for-v7.1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha

2026-04-17T15:34:43+00:00

Pull alpha updates from Magnus Lindholm: "One fix to silence pgprot_modify() compiler warnings, and one patch adding SECCOMP/SECCOMP_FILTER support together with the syscall and ptrace fixes needed for it" * tag 'alpha-for-v7.1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha: alpha: Define pgprot_modify to silence tautological comparison warnings alpha: add support for SECCOMP and SECCOMP_FILTER

alpha: add support for SECCOMP and SECCOMP_FILTER

2026-04-12T17:13:59+00:00

Add SECCOMP and SECCOMP_FILTER support to the Alpha architecture and fix syscall entry and ptrace issues uncovered by the seccomp-bpf selftests. The syscall entry path is reworked to consistently track syscall state using r0, r1 and r2: - r1 holds the active syscall number - r2 preserves the original syscall number for restart - r0 carries the return value, with r19 (a3) indicating success/error This allows syscall restarts to be permitted only for valid ERESTART* return codes and prevents kernel-internal restart values from leaking to userspace. The syscall tracing error marker is corrected to use the saved syscall number slot, matching the Alpha ABI. Additionally, implement minimal PTRACE_GETREGSET and PTRACE_SETREGSET support for NT_PRSTATUS, exporting struct pt_regs directly. This fixes ptrace-based seccomp tests that previously failed with -EIO. With these changes, seccomp-bpf and ptrace syscall tests pass reliably on Alpha. Tested-by: Michael Cree Signed-off-by: Magnus Lindholm Link: https://lore.kernel.org/r/20260409171439.8759-2-linmag7@gmail.com Signed-off-by: Magnus Lindholm

documentation: update arch features

2026-02-23T21:40:56+00:00

PA-RISC has perf-event support since commit 610cb23bcc75 ("parisc: Add initial kernel-side perf_event support"); and s390 has stackprotector support since commit f5730d44e05e ("s390: Add stackprotector support"). Signed-off-by: Miquel Sabaté Solà Signed-off-by: Jonathan Corbet Message-ID: <20260219234040.3260616-1-mssola@mssola.com>

s390: Document s390 stackprotector support

2026-02-03T11:48:27+00:00

Recently [1] s390 got stackprotector support. Document this. [1] commit f5730d44e05e ("s390: Add stackprotector support") Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens

Merge tag 'uml-for-linux-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux

2025-12-06T00:30:56+00:00

Pull UML updates from Johannes Berg: "Apart from the usual small churn, we have - initial SMP support (only kernel) - major vDSO cleanups (and fixes for 32-bit)" * tag 'uml-for-linux-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (33 commits) um: Disable KASAN_INLINE when STATIC_LINK is selected um: Don't rename vmap to kernel_vmap um: drivers: virtio: use string choices helper um: Always set up AT_HWCAP and AT_PLATFORM x86/um: Remove FIXADDR_USER_START and FIXADDR_USE_END um: Remove __access_ok_vsyscall() um: Remove redundant range check from __access_ok_vsyscall() um: Remove fixaddr_user_init() x86/um: Drop gate area handling x86/um: Do not inherit vDSO from host um: Split out default elf_aux_hwcap x86/um: Move ELF_PLATFORM fallback to x86-specific code um: Split out default elf_aux_platform um: Avoid circular dependency on asm-offsets in pgtable.h um: Enable SMP support on x86 asm-generic: percpu: Add assembly guard um: vdso: Remove getcpu support on x86 um: Add initial SMP support um: Define timers on a per-CPU basis um: Determine sleep based on need_resched() ...

docs: Move the "features" tools to tools/docs

2025-10-28T22:01:00+00:00

The scripts for managing the features docs are found in three different directories; unite them all under tools/docs and update references as needed. Reviewed-by: Mauro Carvalho Chehab Acked-by: Jani Nikula Signed-off-by: Jonathan Corbet

um: Add initial SMP support

2025-10-27T15:41:15+00:00

Add initial symmetric multi-processing (SMP) support to UML. With this support enabled, users can tell UML to start multiple virtual processors, each represented as a separate host thread. In UML, kthreads and normal threads (when running in kernel mode) can be scheduled and executed simultaneously on different virtual processors. However, the userspace code of normal threads still runs within their respective single-threaded stubs. That is, SMP support is currently available both within the kernel and across different processes, but still remains limited within threads of the same process in userspace. Signed-off-by: Tiwei Bie Link: https://patch.msgid.link/20251027001815.1666872-6-tiwei.bie@linux.dev Signed-off-by: Johannes Berg

Merge tag 'for-linus' of https://github.com/openrisc/linux

2025-10-05T17:02:54+00:00

Pull OpenRISC updates from Stafford Horne: "I picked up one series from Chen Miao, our Google Summer of Code contributor, which adds OpenRISC support for static keys" * tag 'for-linus' of https://github.com/openrisc/linux: openrisc: Add jump label support openrisc: Regenerate defconfigs. openrisc: Add R_OR1K_32_PCREL relocation type module support openrisc: Add text patching API support

Documentation/features: Update feature lists for 6.17-rc7

2025-09-25T17:17:56+00:00

It seems that ./Documentation/features/scripts/features-refresh.sh was most recently used in December 2022, with the latest kernel release v6.1-rc7 at that time (see commit 7f2e60ff51ca ("Documentation/features: Update feature lists for 6.1") to update the feature lists in this subdirectory. All further changes to Documentation/features/ since then have probably been done manually, without checking for changes in other architectures and features, that missed to update this part of the documentation. Running ./Documentation/features/scripts/features-refresh.sh now showed seven changes of supported features in various architectures (one in arc, two in parisc, one in riscv, one in openrisc, and two in um), which were not reflected yet in the current documentation. To confirm the sanity of this script's suggested changes, I checked if the commit messages confirm that the features have in fact been added in the following commits: - commit f122668ddcce ("ARC: Add eBPF JIT support") - commit 4800a6215e33 ("parisc: Wire up eBPF JIT compiler") - commit a869b8c29f86 ("riscv: enable mseal sysmap for RV64") - commit 2f681ba4b352 ("um: move thread info into task") - commit 3f17fed21491 ("um: switch to regset API and depend on XSTATE") - commit 7ce8716e2769 ("openrisc: Add HAVE_REGS_AND_STACK_ACCESS_API support") - commit b5ff52be8913 ("parisc: Convert to generic clockevents") So, update all documents to the current state with features-refresh.sh. Signed-off-by: Lukas Bulwahn Signed-off-by: Jonathan Corbet Message-ID: <20250925073634.112142-1-lukas.bulwahn@redhat.com>

openrisc: Add jump label support

2025-09-11T10:27:59+00:00

Supported a complete jump_label implementation based on the ARM64 and RV64 version and add the CONFIG_JUMP_LABEL=y to the defconfig. Testing was conducted using a dedicated test module jump-label-test, provided in the link below. For detailed steps, please refer to the README also at the provided link. Link: https://github.com/ChenMiaoi/GSoC-2025-Final-Report/tree/main/tests/jump-label-test Test Environment: - Hardware: QEMU emulated OR1K - Kernel Version: 6.17.0-rc3-dirty - Configs: CONFIG_MODULES=y,CONFIG_MODULE_UNLOAD=y - Toolchain: or1k-none-linux-musl-gcc 15.1.0 Test Results: $ insmod jump_label_test.ko [ 32.590000] Jump label performance test module loaded [ 35.250000] Normal branch time: 1241327150 ns (124 ns per iteration) [ 35.250000] Jump label (false) time: 706422700 ns (70 ns per iteration) [ 35.250000] Jump label (true) time: 708913450 ns (70 ns per iteration) $ rmmod jump_label_test.ko [ 72.210000] Jump label test module unloaded The results show approximately 43% improvement in branch performance when using jump labels compared to traditional branches. Link: https://lore.kernel.org/openrisc/aLsZ9S3X0OpKy1RM@antec/T/#u Signed-off-by: chenmiao Signed-off-by: Stafford Horne