From edd3cb05c00a040dc72bed20b14b5ba865188bce Mon Sep 17 00:00:00 2001 From: Simon Schuster Date: Mon, 1 Sep 2025 15:09:51 +0200 Subject: copy_process: pass clone_flags as u64 across calltree With the introduction of clone3 in commit 7f192e3cd316 ("fork: add clone3") the effective bit width of clone_flags on all architectures was increased from 32-bit to 64-bit, with a new type of u64 for the flags. However, for most consumers of clone_flags the interface was not changed from the previous type of unsigned long. While this works fine as long as none of the new 64-bit flag bits (CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still undesirable in terms of the principle of least surprise. Thus, this commit fixes all relevant interfaces of callees to sys_clone3/copy_process (excluding the architecture-specific copy_thread) to consistently pass clone_flags as u64, so that no truncation to 32-bit integers occurs on 32-bit architectures. Signed-off-by: Simon Schuster Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-2-53fcf5577d57@siemens-energy.com Acked-by: David Hildenbrand Reviewed-by: Lorenzo Stoakes Reviewed-by: Arnd Bergmann Signed-off-by: Christian Brauner --- kernel/sched/core.c | 4 ++-- kernel/sched/fair.c | 2 +- kernel/sched/sched.h | 4 ++-- 3 files changed, 5 insertions(+), 5 deletions(-) (limited to 'kernel/sched') diff --git a/kernel/sched/core.c b/kernel/sched/core.c index be00629f0ba4..6fa85d30d965 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4472,7 +4472,7 @@ int wake_up_state(struct task_struct *p, unsigned int state) * __sched_fork() is basic setup which is also used by sched_init() to * initialize the boot CPU's idle task. */ -static void __sched_fork(unsigned long clone_flags, struct task_struct *p) +static void __sched_fork(u64 clone_flags, struct task_struct *p) { p->on_rq = 0; @@ -4707,7 +4707,7 @@ late_initcall(sched_core_sysctl_init); /* * fork()/clone()-time setup: */ -int sched_fork(unsigned long clone_flags, struct task_struct *p) +int sched_fork(u64 clone_flags, struct task_struct *p) { __sched_fork(clone_flags, p); /* diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b173a059315c..af0866ce2dfc 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3542,7 +3542,7 @@ out: } } -void init_numa_balancing(unsigned long clone_flags, struct task_struct *p) +void init_numa_balancing(u64 clone_flags, struct task_struct *p) { int mm_users = 0; struct mm_struct *mm = p->mm; diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index be9745d104f7..f9adfc912ddc 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1935,12 +1935,12 @@ extern void sched_setnuma(struct task_struct *p, int node); extern int migrate_task_to(struct task_struct *p, int cpu); extern int migrate_swap(struct task_struct *p, struct task_struct *t, int cpu, int scpu); -extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p); +extern void init_numa_balancing(u64 clone_flags, struct task_struct *p); #else /* !CONFIG_NUMA_BALANCING: */ static inline void -init_numa_balancing(unsigned long clone_flags, struct task_struct *p) +init_numa_balancing(u64 clone_flags, struct task_struct *p) { } -- cgit v1.2.3