Re: [PATCH] exit.c: Fix Sparse errors and warnings

From: Madhuparna Bhowmik
Date: Wed Jan 29 2020 - 11:02:15 EST


On Wed, Jan 29, 2020 at 01:30:47PM +0100, Oleg Nesterov wrote:
> On 01/28, madhuparnabhowmik10@xxxxxxxxx wrote:
> >
> > kernel/exit.c:626:40: warning: incorrect type in assignment
> >
> > Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@xxxxxxxxx>
> > ---
> > kernel/exit.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/kernel/exit.c b/kernel/exit.c
> > index bcbd59888e67..c5a9d6360440 100644
> > --- a/kernel/exit.c
> > +++ b/kernel/exit.c
> > @@ -623,8 +623,8 @@ static void forget_original_parent(struct task_struct *father,
> > reaper = find_new_reaper(father, reaper);
> > list_for_each_entry(p, &father->children, sibling) {
> > for_each_thread(p, t) {
> > - t->real_parent = reaper;
> > - BUG_ON((!t->ptrace) != (t->parent == father));
> > + rcu_assign_pointer(t->real_parent, reaper);
>
> Another case when RCU_INIT_POINTER() makes more sense (although to me it
> too looks confusing). We didn't modify the new parent.
>
Alright, I will resend this patch with RCU_INIT_POINTER().

Thank you,
Madhuparna

> Oleg.
>