4 files changed, 21 insertions, 1 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index d25acf600a32..2db1485f865d 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1486,6 +1486,7 @@ static inline void put_task_struct(struct task_struct *t)
 #define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
 #define PF_SPREAD_PAGE  0x01000000      /* Spread page cache over cpuset */
 #define PF_SPREAD_SLAB  0x02000000      /* Spread some slab caches over cpuset */
+#define PF_THREAD_BOUND 0x04000000      /* Thread bound to specific cpu */
 #define PF_MEMPOLICY    0x10000000      /* Non-default NUMA mempolicy */
 #define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
 #define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezeable */
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 6090d18b58a9..b84354f4de36 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1190,6 +1190,15 @@ static int cpuset_can_attach(struct cgroup_subsys *ss,
 
         if (cpus_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
                 return -ENOSPC;
+        if (tsk->flags & PF_THREAD_BOUND) {
+                cpumask_t mask;
+
+                mutex_lock(&callback_mutex);
+                mask = cs->cpus_allowed;
+                mutex_unlock(&callback_mutex);
+                if (!cpus_equal(tsk->cpus_allowed, mask))
+                        return -EINVAL;
+        }
 
         return security_task_setscheduler(tsk, 0, NULL);
 }
@@ -1203,11 +1212,14 @@ static void cpuset_attach(struct cgroup_subsys *ss,
         struct mm_struct *mm;
         struct cpuset *cs = cgroup_cs(cont);
         struct cpuset *oldcs = cgroup_cs(oldcont);
+        int err;
 
         mutex_lock(&callback_mutex);
         guarantee_online_cpus(cs, &cpus);
-        set_cpus_allowed_ptr(tsk, &cpus);
+        err = set_cpus_allowed_ptr(tsk, &cpus);
         mutex_unlock(&callback_mutex);
+        if (err)
+                return;
 
         from = oldcs->mems_allowed;
         to = cs->mems_allowed;
diff --git a/kernel/kthread.c b/kernel/kthread.c
index bd1b9ea024e1..97747cdd37c9 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -180,6 +180,7 @@ void kthread_bind(struct task_struct *k, unsigned int cpu)
         set_task_cpu(k, cpu);
         k->cpus_allowed = cpumask_of_cpu(cpu);
         k->rt.nr_cpus_allowed = 1;
+        k->flags |= PF_THREAD_BOUND;
 }
 EXPORT_SYMBOL(kthread_bind);
 
diff --git a/kernel/sched.c b/kernel/sched.c
index e9c24a128655..164fe7fe0d89 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5563,6 +5563,12 @@ int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
                 goto out;
         }
 
+        if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
+                     !cpus_equal(p->cpus_allowed, *new_mask))) {
+                ret = -EINVAL;
+                goto out;
+        }
+
         if (p->sched_class->set_cpus_allowed)
                 p->sched_class->set_cpus_allowed(p, new_mask);
         else {