1 files changed, 17 insertions, 1 deletions

diff --git a/init/main.c b/init/main.c
index 106e02d7ffa5..40aaa020cd68 100644
--- a/init/main.c
+++ b/init/main.c
@@ -149,6 +149,20 @@ static int __init nosmp(char *str)
 
 early_param("nosmp", nosmp);
 
+/* this is hard limit */
+static int __init nrcpus(char *str)
+{
+        int nr_cpus;
+
+        get_option(&str, &nr_cpus);
+        if (nr_cpus > 0 && nr_cpus < nr_cpu_ids)
+                nr_cpu_ids = nr_cpus;
+
+        return 0;
+}
+
+early_param("nr_cpus", nrcpus);
+
 static int __init maxcpus(char *str)
 {
         get_option(&str, &setup_max_cpus);
@@ -416,7 +430,9 @@ static noinline void __init_refok rest_init(void)
         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();
         unlock_kernel();
 
         /*
@@ -584,6 +600,7 @@ asmlinkage void __init start_kernel(void)
                 local_irq_disable();
         }
         rcu_init();
+        radix_tree_init();
         /* init some links before init_ISA_irqs() */
         early_irq_init();
         init_IRQ();
@@ -657,7 +674,6 @@ asmlinkage void __init start_kernel(void)
         proc_caches_init();
         buffer_init();
         key_init();
-        radix_tree_init();
         security_init();
         vfs_caches_init(totalram_pages);
         signals_init();