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

David Howells
2009-12-11T13:50:48Z

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.

David