CPU HOTPLUG: avoid hotadd when proper possible_map isn't specified
cpu-hot-add should be fail if cpu is not set in cpu_possible_map. If go
ahead, the system will panic soon.
Especially, arch which requires additional_cpus= parameter should handle
this. Tested on ia64.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index ebf6647..6b3a0c1 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -265,6 +265,15 @@
int __cpuinit cpu_up(unsigned int cpu)
{
int err = 0;
+ if (!cpu_isset(cpu, cpu_possible_map)) {
+ printk(KERN_ERR "can't online cpu %d because it is not "
+ "configured as may-hotadd at boot time\n", cpu);
+#if defined(CONFIG_IA64) || defined(CONFIG_X86_64) || defined(CONFIG_S390)
+ printk(KERN_ERR "please check additional_cpus= boot "
+ "parameter\n");
+#endif
+ return -EINVAL;
+ }
mutex_lock(&cpu_add_remove_lock);
if (cpu_hotplug_disabled)