[PATCH] Fix CPU bitmask truncation

Fix task->cpus_allowed bitmask truncations on 64.bit architectures.

Originally by Bjorn Helgaas for 2.4.x.

include/linux/init_task.h

@@ -63,7 +63,7 @@
 	.prio		= MAX_PRIO-20,					\
 	.static_prio	= MAX_PRIO-20,					\
 	.policy		= SCHED_NORMAL,					\
-	.cpus_allowed	= -1,						\
+	.cpus_allowed	= ~0UL,						\
 	.mm		= NULL,						\
 	.active_mm	= &init_mm,					\
 	.run_list	= LIST_HEAD_INIT(tsk.run_list),			\

kernel/module.c

@@ -210,7 +210,7 @@ static int stopref(void *cpu)
 	struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
 	setscheduler(current->pid, SCHED_FIFO, &param);
 #endif
-	set_cpus_allowed(current, 1 << (unsigned long)cpu);
+	set_cpus_allowed(current, 1UL << (unsigned long)cpu);
 
 	/* Ack: we are alive */
 	atomic_inc(&stopref_thread_ack);
@@ -271,7 +271,7 @@ static int stop_refcounts(void)
 
 	/* FIXME: racy with set_cpus_allowed. */
 	old_allowed = current->cpus_allowed;
-	set_cpus_allowed(current, 1 << (unsigned long)cpu);
+	set_cpus_allowed(current, 1UL << (unsigned long)cpu);
 
 	atomic_set(&stopref_thread_ack, 0);
 	stopref_num_threads = 0;