From mboxrd@z Thu Jan  1 00:00:00 1970
From: mulyadi.santosa@gmail.com (Mulyadi Santosa)
Date: Tue, 6 Mar 2012 22:30:29 +0700
Subject: suspicious RCU usage?
In-Reply-To: <CA+MoWDq2tuZcwNxAuUi7EzxyiOu1noPJAKqxywiJtvUgzk+99A@mail.gmail.com>
References: <CA+MoWDq2tuZcwNxAuUi7EzxyiOu1noPJAKqxywiJtvUgzk+99A@mail.gmail.com>
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To: kernelnewbies@lists.kernelnewbies.org
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Hi.... :)

On Sun, Mar 4, 2012 at 20:16, Peter Senna Tschudin
<peter.senna@gmail.com> wrote:
> [ ?858.634435] kernel/pid.c:425 find_task_by_pid_ns() needs
> rcu_read_lock() protection!

hmm....ok....kernel said that.... so...

> int yfkm2_is_pid_running(pid_t pid)
> {
> ? ? ? ?struct task_struct *q;
>
> ? ? ? ?q = find_task_by_vpid(pid);

I think this section that makes kernel barf. It wants you to grab
rcu_read_lock(), right before you do find_task_by_vpid().

What do you think? :)

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com