---

yaml
---
r: 339122
b: refs/heads/master
c: 80aa1df
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f78cff48c3d13636705851b0a9e733db117d58ee
+refs/heads/master: 80aa1dff65717e7518647d4e27d1d3dcea5818e6

trunk/arch/x86/Kconfig

@@ -1698,6 +1698,35 @@ config HOTPLUG_CPU
 	    automatically on SMP systems. )
 	  Say N if you want to disable CPU hotplug.
 
+config BOOTPARAM_HOTPLUG_CPU0
+	bool "Set default setting of cpu0_hotpluggable"
+	default n
+	depends on HOTPLUG_CPU && EXPERIMENTAL
+	---help---
+	  Set whether default state of cpu0_hotpluggable is on or off.
+
+	  Say Y here to enable CPU0 hotplug by default. If this switch
+	  is turned on, there is no need to give cpu0_hotplug kernel
+	  parameter and the CPU0 hotplug feature is enabled by default.
+
+	  Please note: there are two known CPU0 dependencies if you want
+	  to enable the CPU0 hotplug feature either by this switch or by
+	  cpu0_hotplug kernel parameter.
+
+	  First, resume from hibernate or suspend always starts from CPU0.
+	  So hibernate and suspend are prevented if CPU0 is offline.
+
+	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
+	  offline if any interrupt can not migrate out of CPU0. There may
+	  be other CPU0 dependencies.
+
+	  Please make sure the dependencies are under your control before
+	  you enable this feature.
+
+	  Say N if you don't want to enable CPU0 hotplug feature by default.
+	  You still can enable the CPU0 hotplug feature at boot by kernel
+	  parameter cpu0_hotplug.
+
 config COMPAT_VDSO
 	def_bool y
 	prompt "Compat VDSO support"