i386, x86-64: show that CONFIG_HOTPLUG_CPU is required for suspend on SMP
It's not sufficiently documented that CONFIG_HOTPLUG_CPU is required for
suspend/hibernation on SMP.
Point out the non-obvious.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index c2d54b8..8770a5d 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -891,7 +891,7 @@
Don't change this unless you know what you are doing.
config HOTPLUG_CPU
- bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
+ bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
---help---
Say Y here to experiment with turning CPUs off and on, and to
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 145bb82..5ce9443 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -428,12 +428,15 @@
memory in the static kernel configuration.
config HOTPLUG_CPU
- bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
+ bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
depends on SMP && HOTPLUG && EXPERIMENTAL
help
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu/cpu#.
- Say N if you want to disable CPU hotplug.
+ This is also required for suspend/hibernation on SMP systems.
+
+ Say N if you want to disable CPU hotplug and don't need to
+ suspend.
config ARCH_ENABLE_MEMORY_HOTPLUG
def_bool y