Re: [patch 4/9] oom: Add missing rcu protection of __task_cred() in dump_tasks

Thomas Gleixner
2009-12-11T13:53:52Z

On Fri, 11 Dec 2009, David Howells wrote:

> Thomas Gleixner <tglx@linutronix.de> wrote:
>
> > + /* Protect __task_cred() access */
> > + rcu_read_lock();
> > printk(KERN_INFO "[%5d] %5d %5d %8lu %8lu %3d %3d %s\n",
> > p->pid, __task_cred(p)->uid, p->tgid, mm->total_vm,
> > get_mm_rss(mm), (int)task_cpu(p), p->signal->oom_adj,
> > p->comm);
> > + rcu_read_unlock();
>
> No. If there's only one access to __task_cred() like this, use
> task_cred_xxx() or one of its wrappers instead:
>
> - p->pid, __task_cred(p)->uid, p->tgid, mm->total_vm,
> + p->pid, task_uid(p), p->tgid, mm->total_vm,
>
> that limits the size of the critical section.

Fair enough.

tglx