Re: [RFC] is_global_init() called on global init sub-thread

[Sergey Senozhatsky <sergey.senozhatsky@gmail.com>]

On (12/31/15 19:08), Serge E. Hallyn wrote:
> > re-upping https://www.redhat.com/archives/linux-audit/2013-December/msg00086.html
> > 
> > Oleg Nesterov wrote:
> > 
> > :Because is_global_init() is only true for the main thread of /sbin/init.
> > :
> > :Just look at oom_unkillable_task(). It tries to not kill init. But, say,
> > :select_bad_process() can happily find a sub-thread of is_global_init()
> > :and still kill it.
> > 
> > this is still the case, isn't it? at least in some -stable kernels.
> > is there (or was there) any reason this change has never been committed?
> > (I'm particularly interested in is_global_init()).
> 
> ...  seems like it makes sense.  Can you remind us which init you're having
> to deal with?
> 

systemd

	-ss

> >  static inline int is_global_init(struct task_struct *tsk)
> >  {
> > -	return tsk->pid == 1;
> > +	return task_tgid_nr(tsk) == 1;
> >  }