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| author |   Eric W. Biederman <ebiederm@xmission.com> | 2022-04-12 10:18:48 -0500 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2022-05-07 09:01:59 -0500 |
| commit | 5bd2e97c868a8a44470950ed01846cab6328e540 (patch) | |
| tree | 7919866d9e44b6c98bfe16f6ac436013ce9e75c0 /arch/arm/kernel | |
| parent | fork: Explicity test for idle tasks in copy_thread (diff) | |
| download | linux-dev-5bd2e97c868a8a44470950ed01846cab6328e540.tar.xz linux-dev-5bd2e97c868a8a44470950ed01846cab6328e540.zip | |
fork: Generalize PF_IO_WORKER handling
Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.
The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.
The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size". These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().
Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/process.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 8e13b426dd26..3d9cace63884 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -242,7 +242,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) { unsigned long clone_flags = args->flags; unsigned long stack_start = args->stack; - unsigned long stk_sz = args->stack_size; unsigned long tls = args->tls; struct thread_info *thread = task_thread_info(p); struct pt_regs *childregs = task_pt_regs(p); @@ -259,15 +258,15 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) thread->cpu_domain = get_domain(); #endif - if (likely(!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))) { + if (likely(!args->fn)) { *childregs = *current_pt_regs(); childregs->ARM_r0 = 0; if (stack_start) childregs->ARM_sp = stack_start; } else { memset(childregs, 0, sizeof(struct pt_regs)); - thread->cpu_context.r4 = stk_sz; - thread->cpu_context.r5 = stack_start; + thread->cpu_context.r4 = (unsigned long)args->fn_arg; + thread->cpu_context.r5 = (unsigned long)args->fn; childregs->ARM_cpsr = SVC_MODE; } thread->cpu_context.pc = (unsigned long)ret_from_fork; |