1 files changed, 15 insertions, 1 deletions

diff --git a/init/main.c b/init/main.c
index 3bdb152f412f..a42fdf4aeba9 100644
--- a/init/main.c
+++ b/init/main.c
@@ -125,7 +125,9 @@ static char *ramdisk_execute_command;
 
 #ifdef CONFIG_SMP
 /* Setup configured maximum number of CPUs to activate */
-unsigned int __initdata setup_max_cpus = NR_CPUS;
+unsigned int setup_max_cpus = NR_CPUS;
+EXPORT_SYMBOL(setup_max_cpus);
+
 
 /*
  * Setup routine for controlling SMP activation
@@ -422,18 +424,26 @@ static void __init setup_command_line(char *command_line)
  * gcc-3.4 accidentally inlines this function, so use noinline.
  */
 
+static __initdata DECLARE_COMPLETION(kthreadd_done);
+
 static noinline void __init_refok rest_init(void)
         __releases(kernel_lock)
 {
         int pid;
 
         rcu_scheduler_starting();
+        /*
+         * We need to spawn init first so that it obtains pid 1, however
+         * the init task will end up wanting to create kthreads, which, if
+         * we schedule it before we create kthreadd, will OOPS.
+         */
         kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
         numa_default_policy();
         pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
         rcu_read_lock();
         kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
         rcu_read_unlock();
+        complete(&kthreadd_done);
         unlock_kernel();
 
         /*
@@ -855,6 +865,10 @@ static noinline int init_post(void)
 
 static int __init kernel_init(void * unused)
 {
+        /*
+         * Wait until kthreadd is all set-up.
+         */
+        wait_for_completion(&kthreadd_done);
         lock_kernel();
 
         /*