This series adds support for the clone3 system call to the nios2 architecture. This addresses the build-time warning "warning: clone3() entry point is missing, please fix" introduced in 505d66d1abfb9 ("clone3: drop __ARCH_WANT_SYS_CLONE3 macro"). The implementation passes the relevant clone3 tests of kselftest when applied on top of next-20250815:
./run_kselftest.sh TAP version 13 1..4 # selftests: clone3: clone3 ok 1 selftests: clone3: clone3 # selftests: clone3: clone3_clear_sighand ok 2 selftests: clone3: clone3_clear_sighand # selftests: clone3: clone3_set_tid ok 3 selftests: clone3: clone3_set_tid # selftests: clone3: clone3_cap_checkpoint_restore ok 4 selftests: clone3: clone3_cap_checkpoint_restore
The series also includes a small patch to kernel/fork.c that ensures that clone_flags are passed correctly on architectures where unsigned long is insufficient to store the u64 clone_flags. It is marked as a fix for stable backporting.
As requested, in v2, this series now further tries to correct this type error throughout the whole code base. Thus, it now touches a larger number of subsystems and all architectures.
Therefore, another test was performed for ARCH=x86_64 (as a representative for 64-bit architectures). Here, the series builds cleanly without warnings on defconfig with CONFIG_SECURITY_APPARMOR=y and CONFIG_SECURITY_TOMOYO=y (to compile-check the LSM-related changes). The build further successfully passes testing/selftests/clone3 (with the patch from 20241105062948.1037011-1-zhouyuhang1010@163.com to prepare clone3_cap_checkpoint_restore for compatibility with the newer libcap version on my system).
Is there any option to further preflight check this patch series via lkp/KernelCI/etc. for a broader test across architectures, or is this degree of testing sufficient to eventually get the series merged?
N.B.: The series is not checkpatch clean right now: - include/linux/cred.h, include/linux/mnt_namespace.h: function definition arguments without identifier name - include/trace/events/task.h: space prohibited after that open parenthesis
I did not fix these warnings to keep my changes minimal and reviewable, as the issues persist throughout the files and they were not introduced by me; I only followed the existing code style and just replaced the types. If desired, I'd be happy to make the changes in a potential v3, though.
Signed-off-by: Simon Schuster schuster.simon@siemens-energy.com --- Changes in v2: - Introduce "Fixes:" and "Cc: stable@vger.kernel.org" where necessary - Factor out "Fixes:" when adapting the datatype of clone_flags for easier backports - Fix additional instances where `unsigned long` clone_flags is used - Reword commit message to make it clearer that any 32-bit arch is affected by this bug - Link to v1: https://lore.kernel.org/r/20250821-nios2-implement-clone3-v1-0-1bb24017376a@...
--- Simon Schuster (4): copy_sighand: Handle architectures where sizeof(unsigned long) < sizeof(u64) copy_process: pass clone_flags as u64 across calltree arch: copy_thread: pass clone_flags as u64 nios2: implement architecture-specific portion of sys_clone3
arch/alpha/kernel/process.c | 2 +- arch/arc/kernel/process.c | 2 +- arch/arm/kernel/process.c | 2 +- arch/arm64/kernel/process.c | 2 +- arch/csky/kernel/process.c | 2 +- arch/hexagon/kernel/process.c | 2 +- arch/loongarch/kernel/process.c | 2 +- arch/m68k/kernel/process.c | 2 +- arch/microblaze/kernel/process.c | 2 +- arch/mips/kernel/process.c | 2 +- arch/nios2/include/asm/syscalls.h | 1 + arch/nios2/include/asm/unistd.h | 2 -- arch/nios2/kernel/entry.S | 6 ++++++ arch/nios2/kernel/process.c | 2 +- arch/nios2/kernel/syscall_table.c | 1 + arch/openrisc/kernel/process.c | 2 +- arch/parisc/kernel/process.c | 2 +- arch/powerpc/kernel/process.c | 2 +- arch/riscv/kernel/process.c | 2 +- arch/s390/kernel/process.c | 2 +- arch/sh/kernel/process_32.c | 2 +- arch/sparc/kernel/process_32.c | 2 +- arch/sparc/kernel/process_64.c | 2 +- arch/um/kernel/process.c | 2 +- arch/x86/include/asm/fpu/sched.h | 2 +- arch/x86/include/asm/shstk.h | 4 ++-- arch/x86/kernel/fpu/core.c | 2 +- arch/x86/kernel/process.c | 2 +- arch/x86/kernel/shstk.c | 2 +- arch/xtensa/kernel/process.c | 2 +- block/blk-ioc.c | 2 +- fs/namespace.c | 2 +- include/linux/cgroup.h | 4 ++-- include/linux/cred.h | 2 +- include/linux/iocontext.h | 6 +++--- include/linux/ipc_namespace.h | 4 ++-- include/linux/lsm_hook_defs.h | 2 +- include/linux/mnt_namespace.h | 2 +- include/linux/nsproxy.h | 2 +- include/linux/pid_namespace.h | 4 ++-- include/linux/rseq.h | 4 ++-- include/linux/sched/task.h | 2 +- include/linux/security.h | 4 ++-- include/linux/sem.h | 4 ++-- include/linux/time_namespace.h | 4 ++-- include/linux/uprobes.h | 4 ++-- include/linux/user_events.h | 4 ++-- include/linux/utsname.h | 4 ++-- include/net/net_namespace.h | 4 ++-- include/trace/events/task.h | 6 +++--- ipc/namespace.c | 2 +- ipc/sem.c | 2 +- kernel/cgroup/namespace.c | 2 +- kernel/cred.c | 2 +- kernel/events/uprobes.c | 2 +- kernel/fork.c | 10 +++++----- kernel/nsproxy.c | 4 ++-- kernel/pid_namespace.c | 2 +- kernel/sched/core.c | 4 ++-- kernel/sched/fair.c | 2 +- kernel/sched/sched.h | 4 ++-- kernel/time/namespace.c | 2 +- kernel/utsname.c | 2 +- net/core/net_namespace.c | 2 +- security/apparmor/lsm.c | 2 +- security/security.c | 2 +- security/selinux/hooks.c | 2 +- security/tomoyo/tomoyo.c | 2 +- 68 files changed, 95 insertions(+), 89 deletions(-) --- base-commit: 1357b2649c026b51353c84ddd32bc963e8999603 change-id: 20250818-nios2-implement-clone3-7f252c20860b
Best regards,