[PATCH 10/10] exit/kthread: Move the exit code for kernel threads into struct kthread

Eric W. Biederman
2021-12-08T20:26:55Z

The exit code of kernel threads has different semantics than the
exit_code of userspace tasks. To avoid confusion and allow
the userspace implementation to change as needed move
the kernel thread exit code into struct kthread.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
kernel/kthread.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 8e5f44bed027..9c6c532047c4 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -52,6 +52,7 @@ struct kthread_create_info
struct kthread {
unsigned long flags;
unsigned int cpu;
+ int result;
int (*threadfn)(void *);
void *data;
mm_segment_t oldfs;
@@ -287,7 +288,9 @@ EXPORT_SYMBOL_GPL(kthread_parkme);
*/
void __noreturn kthread_exit(long result)
{
- do_exit(result);
+ struct kthread *kthread = to_kthread(current);
+ kthread->result = result;
+ do_exit(0);
}

/**
@@ -679,7 +682,7 @@ int kthread_stop(struct task_struct *k)
kthread_unpark(k);
wake_up_process(k);
wait_for_completion(&kthread->exited);
- ret = k->exit_code;
+ ret = kthread->result;
put_task_struct(k);

trace_sched_kthread_stop_ret(ret);
--
2.29.2