Re: [PATCH 2/2] cgroup: Add a allow_attach policy for Android

From: John Stultz
Date: Wed Oct 05 2016 - 15:18:23 EST


On Wed, Oct 5, 2016 at 12:10 PM, Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
> On Mon, Oct 03, 2016 at 09:41:30PM -0700, John Stultz wrote:
>> +#ifdef CONFIG_CGROUP_NICE_ATTACH
>> +int cgroup_nice_allow_attach(struct cgroup_taskset *tset)
>> +{
>> + const struct cred *cred = current_cred(), *tcred;
>> + struct task_struct *task;
>> + struct cgroup_subsys_state *css;
>> +
>> + if (capable(CAP_SYS_NICE))
>> + return 0;
>> +
>> + cgroup_taskset_for_each(task, css, tset) {
>> + tcred = __task_cred(task);
>
> __task_cred() requires RCU lock (courtesy Ricky Z).

Again, hopefully this isn't an issue with the new approach, but for
the short term I'll see if we can get this fixed in the android tree.

Thanks again for your careful review!
-john