1 files changed, 11 insertions, 1 deletions

diff --git a/kernel/kthread.c b/kernel/kthread.c
index dcfe724300eb..0ac887882f90 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -15,6 +15,8 @@
 #include <linux/mutex.h>
 #include <asm/semaphore.h>
 
+#define KTHREAD_NICE_LEVEL (-5)
+
 static DEFINE_SPINLOCK(kthread_create_lock);
 static LIST_HEAD(kthread_create_list);
 struct task_struct *kthreadd_task;
@@ -94,10 +96,18 @@ static void create_kthread(struct kthread_create_info *create)
         if (pid < 0) {
                 create->result = ERR_PTR(pid);
         } else {
+                struct sched_param param = { .sched_priority = 0 };
                 wait_for_completion(&create->started);
                 read_lock(&tasklist_lock);
                 create->result = find_task_by_pid(pid);
                 read_unlock(&tasklist_lock);
+                /*
+                 * root may have changed our (kthreadd's) priority or CPU mask.
+                 * The kernel thread should not inherit these properties.
+                 */
+                sched_setscheduler(create->result, SCHED_NORMAL, &param);
+                set_user_nice(create->result, KTHREAD_NICE_LEVEL);
+                set_cpus_allowed(create->result, CPU_MASK_ALL);
         }
         complete(&create->done);
 }
@@ -221,7 +231,7 @@ int kthreadd(void *unused)
         /* Setup a clean context for our children to inherit. */
         set_task_comm(tsk, "kthreadd");
         ignore_signals(tsk);
-        set_user_nice(tsk, -5);
+        set_user_nice(tsk, KTHREAD_NICE_LEVEL);
         set_cpus_allowed(tsk, CPU_MASK_ALL);
 
         current->flags |= PF_NOFREEZE;