diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 1f2cccc..4231034 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -211,6 +211,13 @@ void __cpuinit __cpu_die(unsigned int cpu)
 	}
 	printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
 
+	/*
+	 * platform_cpu_kill() is generally expected to do the powering off
+	 * and/or cutting of clocks to the dying CPU.  Optionally, this may
+	 * be done by the CPU which is dying in preference to supporting
+	 * this call, but that means there is _no_ synchronisation between
+	 * the requesting CPU and the dying CPU actually losing power.
+	 */
 	if (!platform_cpu_kill(cpu))
 		printk("CPU%u: unable to kill\n", cpu);
 }
@@ -230,14 +237,41 @@ void __ref cpu_die(void)
 	idle_task_exit();
 
 	local_irq_disable();
-	mb();
 
-	/* Tell __cpu_die() that this CPU is now safe to dispose of */
+	/*
+	 * Flush the data out of the L1 cache for this CPU.  This must be
+	 * before the completion to ensure that data is safely written out
+	 * before platform_cpu_kill() gets called - which may disable
+	 * *this* CPU and power down its cache.
+	 */
+	flush_cache_louis();
+
+	/*
+	 * Tell __cpu_die() that this CPU is now safe to dispose of.  Once
+	 * this returns, power and/or clocks can be removed at any point
+	 * from this CPU and its cache by platform_cpu_kill().
+	 */
 	RCU_NONIDLE(complete(&cpu_died));
 
 	/*
-	 * actual CPU shutdown procedure is at least platform (if not
-	 * CPU) specific.
+	 * Ensure that the cache lines associated with that completion are
+	 * written out.  This covers the case where _this_ CPU is doing the
+	 * powering down, to ensure that the completion is visible to the
+	 * CPU waiting for this one.
+	 */
+	flush_cache_louis();
+
+	/*
+	 * The actual CPU shutdown procedure is at least platform (if not
+	 * CPU) specific.  This may remove power, or it may simply spin.
+	 *
+	 * Platforms are generally expected *NOT* to return from this call,
+	 * although there are some which do because they have no way to
+	 * power down the CPU.  These platforms are the _only_ reason we
+	 * have a return path which uses the fragment of assembly below.
+	 *
+	 * The return path should not be used for platforms which can
+	 * power off the CPU.
 	 */
 	if (smp_ops.cpu_die)
 		smp_ops.cpu_die(cpu);
diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
index c3f825b..af90cfa 100644
--- a/arch/arm/mach-exynos/hotplug.c
+++ b/arch/arm/mach-exynos/hotplug.c
@@ -28,7 +28,6 @@ static inline void cpu_enter_lowpower_a9(void)
 {
 	unsigned int v;
 
-	flush_cache_all();
 	asm volatile(
 	"	mcr	p15, 0, %1, c7, c5, 0\n"
 	"	mcr	p15, 0, %1, c7, c10, 4\n"
diff --git a/arch/arm/mach-highbank/hotplug.c b/arch/arm/mach-highbank/hotplug.c
index f30c528..35dd42e 100644
--- a/arch/arm/mach-highbank/hotplug.c
+++ b/arch/arm/mach-highbank/hotplug.c
@@ -15,8 +15,6 @@
  */
 #include <linux/kernel.h>
 
-#include <asm/cacheflush.h>
-
 #include "core.h"
 #include "sysregs.h"
 
@@ -28,8 +26,6 @@ extern void secondary_startup(void);
  */
 void __ref highbank_cpu_die(unsigned int cpu)
 {
-	flush_cache_all();
-
 	highbank_set_cpu_jump(cpu, phys_to_virt(0));
 	highbank_set_core_pwr();
 
diff --git a/arch/arm/mach-imx/hotplug.c b/arch/arm/mach-imx/hotplug.c
index 361a253..5e91112 100644
--- a/arch/arm/mach-imx/hotplug.c
+++ b/arch/arm/mach-imx/hotplug.c
@@ -11,7 +11,6 @@
  */
 
 #include <linux/errno.h>
-#include <asm/cacheflush.h>
 #include <asm/cp15.h>
 
 #include "common.h"
@@ -20,7 +19,6 @@ static inline void cpu_enter_lowpower(void)
 {
 	unsigned int v;
 
-	flush_cache_all();
 	asm volatile(
 		"mcr	p15, 0, %1, c7, c5, 0\n"
 	"	mcr	p15, 0, %1, c7, c10, 4\n"
diff --git a/arch/arm/mach-msm/hotplug.c b/arch/arm/mach-msm/hotplug.c
index 750446f..326a872 100644
--- a/arch/arm/mach-msm/hotplug.c
+++ b/arch/arm/mach-msm/hotplug.c
@@ -10,16 +10,12 @@
 #include <linux/errno.h>
 #include <linux/smp.h>
 
-#include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
 
 #include "common.h"
 
 static inline void cpu_enter_lowpower(void)
 {
-	/* Just flush the cache. Changing the coherency is not yet
-	 * available on msm. */
-	flush_cache_all();
 }
 
 static inline void cpu_leave_lowpower(void)
diff --git a/arch/arm/mach-omap2/omap-hotplug.c b/arch/arm/mach-omap2/omap-hotplug.c
index e712d17..ceb30a5 100644
--- a/arch/arm/mach-omap2/omap-hotplug.c
+++ b/arch/arm/mach-omap2/omap-hotplug.c
@@ -35,9 +35,6 @@ void __ref omap4_cpu_die(unsigned int cpu)
 	unsigned int boot_cpu = 0;
 	void __iomem *base = omap_get_wakeupgen_base();
 
-	flush_cache_all();
-	dsb();
-
 	/*
 	 * we're ready for shutdown now, so do it
 	 */
diff --git a/arch/arm/mach-prima2/hotplug.c b/arch/arm/mach-prima2/hotplug.c
index f4b17cb..0ab2f8b 100644
--- a/arch/arm/mach-prima2/hotplug.c
+++ b/arch/arm/mach-prima2/hotplug.c
@@ -10,13 +10,10 @@
 #include <linux/errno.h>
 #include <linux/smp.h>
 
-#include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
 
 static inline void platform_do_lowpower(unsigned int cpu)
 {
-	flush_cache_all();
-
 	/* we put the platform to just WFI */
 	for (;;) {
 		__asm__ __volatile__("dsb\n\t" "wfi\n\t"
diff --git a/arch/arm/mach-realview/hotplug.c b/arch/arm/mach-realview/hotplug.c
index 53818e5..ac22dd4 100644
--- a/arch/arm/mach-realview/hotplug.c
+++ b/arch/arm/mach-realview/hotplug.c
@@ -12,7 +12,6 @@
 #include <linux/errno.h>
 #include <linux/smp.h>
 
-#include <asm/cacheflush.h>
 #include <asm/cp15.h>
 #include <asm/smp_plat.h>
 
@@ -20,7 +19,6 @@ static inline void cpu_enter_lowpower(void)
 {
 	unsigned int v;
 
-	flush_cache_all();
 	asm volatile(
 	"	mcr	p15, 0, %1, c7, c5, 0\n"
 	"	mcr	p15, 0, %1, c7, c10, 4\n"
diff --git a/arch/arm/mach-shmobile/smp-sh73a0.c b/arch/arm/mach-shmobile/smp-sh73a0.c
index acb46a9..2f1ef1b 100644
--- a/arch/arm/mach-shmobile/smp-sh73a0.c
+++ b/arch/arm/mach-shmobile/smp-sh73a0.c
@@ -119,14 +119,6 @@ static int sh73a0_cpu_kill(unsigned int cpu)
 
 static void sh73a0_cpu_die(unsigned int cpu)
 {
-	/*
-	 * The ARM MPcore does not issue a cache coherency request for the L1
-	 * cache when powering off single CPUs. We must take care of this and
-	 * further caches.
-	 */
-	dsb();
-	flush_cache_all();
-
 	/* Set power off mode. This takes the CPU out of the MP cluster */
 	scu_power_mode(scu_base_addr(), SCU_PM_POWEROFF);
 
diff --git a/arch/arm/mach-spear13xx/hotplug.c b/arch/arm/mach-spear13xx/hotplug.c
index a7d2dd1..d97749c 100644
--- a/arch/arm/mach-spear13xx/hotplug.c
+++ b/arch/arm/mach-spear13xx/hotplug.c
@@ -13,7 +13,6 @@
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/smp.h>
-#include <asm/cacheflush.h>
 #include <asm/cp15.h>
 #include <asm/smp_plat.h>
 
@@ -21,7 +20,6 @@ static inline void cpu_enter_lowpower(void)
 {
 	unsigned int v;
 
-	flush_cache_all();
 	asm volatile(
 	"	mcr	p15, 0, %1, c7, c5, 0\n"
 	"	dsb\n"
diff --git a/arch/arm/mach-tegra/common.h b/arch/arm/mach-tegra/common.h
index 32f8eb3..5900cc4 100644
--- a/arch/arm/mach-tegra/common.h
+++ b/arch/arm/mach-tegra/common.h
@@ -2,4 +2,3 @@ extern struct smp_operations tegra_smp_ops;
 
 extern int tegra_cpu_kill(unsigned int cpu);
 extern void tegra_cpu_die(unsigned int cpu);
-extern int tegra_cpu_disable(unsigned int cpu);
diff --git a/arch/arm/mach-tegra/hotplug.c b/arch/arm/mach-tegra/hotplug.c
index a599f6e..e8323bc 100644
--- a/arch/arm/mach-tegra/hotplug.c
+++ b/arch/arm/mach-tegra/hotplug.c
@@ -12,7 +12,6 @@
 #include <linux/smp.h>
 #include <linux/clk/tegra.h>
 
-#include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
 
 #include "sleep.h"
@@ -47,15 +46,6 @@ void __ref tegra_cpu_die(unsigned int cpu)
 	BUG();
 }
 
-int tegra_cpu_disable(unsigned int cpu)
-{
-	/*
-	 * we don't allow CPU 0 to be shutdown (it is still too special
-	 * e.g. clock tick interrupts)
-	 */
-	return cpu == 0 ? -EPERM : 0;
-}
-
 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
 extern void tegra20_hotplug_shutdown(void);
 void __init tegra20_hotplug_init(void)
diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c
index 2c6b3d5..ec33ec8 100644
--- a/arch/arm/mach-tegra/platsmp.c
+++ b/arch/arm/mach-tegra/platsmp.c
@@ -192,6 +192,5 @@ struct smp_operations tegra_smp_ops __initdata = {
 #ifdef CONFIG_HOTPLUG_CPU
 	.cpu_kill		= tegra_cpu_kill,
 	.cpu_die		= tegra_cpu_die,
-	.cpu_disable		= tegra_cpu_disable,
 #endif
 };
diff --git a/arch/arm/mach-ux500/hotplug.c b/arch/arm/mach-ux500/hotplug.c
index 2f6af25..1c55a55 100644
--- a/arch/arm/mach-ux500/hotplug.c
+++ b/arch/arm/mach-ux500/hotplug.c
@@ -12,7 +12,6 @@
 #include <linux/errno.h>
 #include <linux/smp.h>
 
-#include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
 
 #include <mach/setup.h>
@@ -24,8 +23,6 @@
  */
 void __ref ux500_cpu_die(unsigned int cpu)
 {
-	flush_cache_all();
-
 	/* directly enter low power state, skipping secure registers */
 	for (;;) {
 		__asm__ __volatile__("dsb\n\t" "wfi\n\t"
diff --git a/arch/arm/mach-vexpress/hotplug.c b/arch/arm/mach-vexpress/hotplug.c
index a141b98..f0ce6b8 100644
--- a/arch/arm/mach-vexpress/hotplug.c
+++ b/arch/arm/mach-vexpress/hotplug.c
@@ -12,7 +12,6 @@
 #include <linux/errno.h>
 #include <linux/smp.h>
 
-#include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
 #include <asm/cp15.h>
 
@@ -20,7 +19,6 @@ static inline void cpu_enter_lowpower(void)
 {
 	unsigned int v;
 
-	flush_cache_all();
 	asm volatile(
 		"mcr	p15, 0, %1, c7, c5, 0\n"
 	"	mcr	p15, 0, %1, c7, c10, 4\n"
