1. rename reparent_to_init() to reparent_kthread() and export it 2. use init_pid_ns.child_reaper instead of child_reaper(current)
3. set ->exit_signal = -1, so init can't see us and we don't use it to reap the task. 4. add reparent_kthread() to kthread() and stopmachine() See also http://marc.info/?t=117580282200003&r=1 http://marc.info/?t=95299284800003&r=1 Signed-off-by: Oleg Nesterov <[EMAIL PROTECTED]> include/linux/sched.h | 1 + kernel/exit.c | 16 ++++++++-------- kernel/kthread.c | 1 + kernel/stop_machine.c | 1 + 4 files changed, 11 insertions(+), 8 deletions(-) --- 2.6.21-rc5/include/linux/sched.h~2_DETACH 2007-04-05 12:18:28.000000000 +0400 +++ 2.6.21-rc5/include/linux/sched.h 2007-04-10 21:52:27.000000000 +0400 @@ -1401,6 +1401,7 @@ extern void exit_itimers(struct signal_s extern NORET_TYPE void do_group_exit(int); +extern void reparent_kthread(void); extern void daemonize(const char *, ...); extern int allow_signal(int); extern int disallow_signal(int); --- 2.6.21-rc5/kernel/exit.c~2_DETACH 2007-04-10 21:32:44.000000000 +0400 +++ 2.6.21-rc5/kernel/exit.c 2007-04-10 21:59:41.000000000 +0400 @@ -255,7 +255,7 @@ static int has_stopped_jobs(struct pid * } /** - * reparent_to_init - Reparent the calling kernel thread to the init task of the pid space that the thread belongs to. + * reparent_kthread - Reparent the calling kernel thread to the init task of the pid space that the thread belongs to. * * If a kernel thread is launched as a result of a system call, or if * it ever exits, it should generally reparent itself to init so that @@ -264,20 +264,20 @@ static int has_stopped_jobs(struct pid * * The various task state such as scheduling policy and priority may have * been inherited from a user process, so we reset them to sane values here. * - * NOTE that reparent_to_init() gives the caller full capabilities. + * NOTE that reparent_kthread() gives the caller full capabilities. */ -static void reparent_to_init(void) +void reparent_kthread(void) { write_lock_irq(&tasklist_lock); ptrace_unlink(current); remove_parent(current); - current->parent = child_reaper(current); - current->real_parent = child_reaper(current); + current->parent = init_pid_ns.child_reaper; + current->real_parent = current->parent; add_parent(current); - /* Set the exit signal to SIGCHLD so we signal init on exit */ - current->exit_signal = SIGCHLD; + /* make the task auto-reap */ + current->exit_signal = -1; security_task_reparent_to_init(current); write_unlock_irq(&tasklist_lock); @@ -391,7 +391,7 @@ void daemonize(const char *name, ...) current->files = init_task.files; atomic_inc(¤t->files->count); - reparent_to_init(); + reparent_kthread(); if (!has_rt_policy(current) && (task_nice(current) < 0)) set_user_nice(current, 0); --- 2.6.21-rc5/kernel/kthread.c~2_DETACH 2007-04-05 12:18:28.000000000 +0400 +++ 2.6.21-rc5/kernel/kthread.c 2007-04-10 22:02:31.000000000 +0400 @@ -82,6 +82,7 @@ static int kthread(void *_create) sigset_t blocked; int ret = -EINTR; + reparent_kthread(); kthread_exit_files(); /* Copy data: it's on keventd's stack */ --- 2.6.21-rc5/kernel/stop_machine.c~2_DETACH 2006-10-22 18:24:03.000000000 +0400 +++ 2.6.21-rc5/kernel/stop_machine.c 2007-04-10 22:04:23.000000000 +0400 @@ -33,6 +33,7 @@ static int stopmachine(void *cpu) int irqs_disabled = 0; int prepared = 0; + reparent_kthread(); set_cpus_allowed(current, cpumask_of_cpu((int)(long)cpu)); /* Ack: we are alive */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/