From: Peter Zijlstra <peterz@infradead.org>
To: paulmck@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org, mingo@elte.hu,
laijs@cn.fujitsu.com, dipankar@in.ibm.com,
akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca,
josh@joshtriplett.org, dvhltc@us.ibm.com, niv@us.ibm.com,
tglx@linutronix.de, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu,
dhowells@redhat.com, eric.dumazet@gmail.com, abogani@texware.it
Subject: Re: [PATCH tip/core/urgent] rcu: protect fork-time cgroup access
Date: Mon, 29 Mar 2010 23:19:23 +0200 [thread overview]
Message-ID: <1269897564.12097.372.camel@laptop> (raw)
In-Reply-To: <20100329211525.GA17703@linux.vnet.ibm.com>
On Mon, 2010-03-29 at 14:15 -0700, Paul E. McKenney wrote:
> Add an rcu_read_lock() / rcu_read_unlock() pair to protect a fork-time
> cgroup access. This seems likely to be a false positive.
>
> Located by: Alessio Igor Bogani <abogani@texware.it>
> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> ---
>
> sched.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/kernel/sched.c b/kernel/sched.c
> index 9ab3cd7..d4bb5e0 100644
> --- a/kernel/sched.c
> +++ b/kernel/sched.c
> @@ -2621,7 +2621,9 @@ void sched_fork(struct task_struct *p, int clone_flags)
> if (p->sched_class->task_fork)
> p->sched_class->task_fork(p);
>
> + rcu_read_lock();
> set_task_cpu(p, cpu);
> + rcu_read_unlock();
>
> #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
> if (likely(sched_info_on()))
What got accessed? This patch just looks wrong.
next prev parent reply other threads:[~2010-03-29 21:19 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-29 21:15 [PATCH tip/core/urgent] rcu: protect fork-time cgroup access Paul E. McKenney
2010-03-29 21:19 ` Peter Zijlstra [this message]
2010-03-29 21:26 ` Peter Zijlstra
2010-03-29 22:24 ` Paul E. McKenney
2010-03-29 21:29 ` Paul E. McKenney
2010-03-29 21:34 ` Paul E. McKenney
2010-03-29 21:42 ` Peter Zijlstra
2010-03-29 21:51 ` Paul E. McKenney
2010-03-29 22:43 ` Paul Menage
2010-03-29 23:05 ` Paul E. McKenney
2010-03-30 18:57 ` Paul Menage
2010-03-30 8:50 ` Peter Zijlstra
2010-03-30 17:28 ` Paul E. McKenney
-- strict thread matches above, loose matches on Subject: below --
2010-03-30 9:32 Matt Helsley
2010-03-30 17:26 ` Paul E. McKenney
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