lkml.org 
[lkml]   [2010]   [Apr]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: INFO: suspicious rcu_dereference_check() usage - include/linux/cgroup.h:492 invoked rcu_dereference_check() without protection!
Should be [tip:core/urgent]

Acked-by: Lai Jiangshan <laijs@cn.fujitsu.com>

Paul E. McKenney wrote:
>
> Looks reasonable to me!
>
> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
>
>> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
>> ---
>> kernel/sched.c | 10 ++++++++++
>> 1 files changed, 10 insertions(+), 0 deletions(-)
>>
>> diff --git a/kernel/sched.c b/kernel/sched.c
>> index 3acf694..2e06d87 100644
>> --- a/kernel/sched.c
>> +++ b/kernel/sched.c
>> @@ -323,6 +323,15 @@ static inline struct task_group *task_group(struct task_struct *p)
>> /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
>> static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
>> {
>> + /*
>> + * Strictly speaking this rcu_read_lock() is not needed since the
>> + * task_group is tied to the cgroup, which in turn can never go away
>> + * as long as there are tasks attached to it.
>> + *
>> + * However since task_group() uses task_subsys_state() which is an
>> + * rcu_dereference() user, this quiets CONFIG_PROVE_RCU.
>> + */
>> + rcu_read_lock();
>> #ifdef CONFIG_FAIR_GROUP_SCHED
>> p->se.cfs_rq = task_group(p)->cfs_rq[cpu];
>> p->se.parent = task_group(p)->se[cpu];
>> @@ -332,6 +341,7 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
>> p->rt.rt_rq = task_group(p)->rt_rq[cpu];
>> p->rt.parent = task_group(p)->rt_se[cpu];
>> #endif
>> + rcu_read_unlock();
>> }
>>
>> #else
>>
>>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
>



\
 
 \ /
  Last update: 2010-04-19 05:49    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site