diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 47768ff87343d27d2cc5228aa6e02f6cfdff20a0..80998958cf45381f4e1ef6f585b9467b31d1e4b3 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -208,7 +208,7 @@ config ACPI_IPMI
 
 config ACPI_HOTPLUG_CPU
 	bool
-	depends on ACPI_PROCESSOR && HOTPLUG_CPU
+	depends on EXPERIMENTAL && ACPI_PROCESSOR && HOTPLUG_CPU
 	select ACPI_CONTAINER
 	default y
 
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 86933ca8b4724372505530de753332907f488ebe..7dd3f9fb9f3f21b808e30b8aa78f65fce7b2275a 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -643,11 +643,19 @@ static int acpi_battery_update(struct acpi_battery *battery)
 
 static void acpi_battery_refresh(struct acpi_battery *battery)
 {
+	int power_unit;
+
 	if (!battery->bat.dev)
 		return;
 
+	power_unit = battery->power_unit;
+
 	acpi_battery_get_info(battery);
-	/* The battery may have changed its reporting units. */
+
+	if (power_unit == battery->power_unit)
+		return;
+
+	/* The battery has changed its reporting units. */
 	sysfs_remove_battery(battery);
 	sysfs_add_battery(battery);
 }
diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c
index 0af48a8554cd786620266c5449fb82798f034de1..a093dc163a42a8b677d9ccb7b27a61d0427c3f49 100644
--- a/drivers/acpi/processor_perflib.c
+++ b/drivers/acpi/processor_perflib.c
@@ -333,6 +333,7 @@ static int acpi_processor_get_performance_states(struct acpi_processor *pr)
 	struct acpi_buffer state = { 0, NULL };
 	union acpi_object *pss = NULL;
 	int i;
+	int last_invalid = -1;
 
 
 	status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
@@ -394,14 +395,33 @@ static int acpi_processor_get_performance_states(struct acpi_processor *pr)
 		    ((u32)(px->core_frequency * 1000) !=
 		     (px->core_frequency * 1000))) {
 			printk(KERN_ERR FW_BUG PREFIX
-			       "Invalid BIOS _PSS frequency: 0x%llx MHz\n",
-			       px->core_frequency);
-			result = -EFAULT;
-			kfree(pr->performance->states);
-			goto end;
+			       "Invalid BIOS _PSS frequency found for processor %d: 0x%llx MHz\n",
+			       pr->id, px->core_frequency);
+			if (last_invalid == -1)
+				last_invalid = i;
+		} else {
+			if (last_invalid != -1) {
+				/*
+				 * Copy this valid entry over last_invalid entry
+				 */
+				memcpy(&(pr->performance->states[last_invalid]),
+				       px, sizeof(struct acpi_processor_px));
+				++last_invalid;
+			}
 		}
 	}
 
+	if (last_invalid == 0) {
+		printk(KERN_ERR FW_BUG PREFIX
+		       "No valid BIOS _PSS frequency found for processor %d\n", pr->id);
+		result = -EFAULT;
+		kfree(pr->performance->states);
+		pr->performance->states = NULL;
+	}
+
+	if (last_invalid > 0)
+		pr->performance->state_count = last_invalid;
+
       end:
 	kfree(buffer.pointer);
 
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 9577b6fa26507cad1db1f2ddf7d6f114abfdf513..a576575617d733f88960b849869fec4eb413f75d 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1687,10 +1687,6 @@ static int acpi_video_bus_add(struct acpi_device *device)
 	set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
 	set_bit(KEY_DISPLAY_OFF, input->keybit);
 
-	error = input_register_device(input);
-	if (error)
-		goto err_stop_video;
-
 	printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
 	       ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
 	       video->flags.multihead ? "yes" : "no",
@@ -1701,12 +1697,16 @@ static int acpi_video_bus_add(struct acpi_device *device)
 	video->pm_nb.priority = 0;
 	error = register_pm_notifier(&video->pm_nb);
 	if (error)
-		goto err_unregister_input_dev;
+		goto err_stop_video;
+
+	error = input_register_device(input);
+	if (error)
+		goto err_unregister_pm_notifier;
 
 	return 0;
 
- err_unregister_input_dev:
-	input_unregister_device(input);
+ err_unregister_pm_notifier:
+	unregister_pm_notifier(&video->pm_nb);
  err_stop_video:
 	acpi_video_bus_stop_devices(video);
  err_free_input_dev:
@@ -1743,9 +1743,18 @@ static int acpi_video_bus_remove(struct acpi_device *device, int type)
 	return 0;
 }
 
+static int __init is_i740(struct pci_dev *dev)
+{
+	if (dev->device == 0x00D1)
+		return 1;
+	if (dev->device == 0x7000)
+		return 1;
+	return 0;
+}
+
 static int __init intel_opregion_present(void)
 {
-#if defined(CONFIG_DRM_I915) || defined(CONFIG_DRM_I915_MODULE)
+	int opregion = 0;
 	struct pci_dev *dev = NULL;
 	u32 address;
 
@@ -1754,13 +1763,15 @@ static int __init intel_opregion_present(void)
 			continue;
 		if (dev->vendor != PCI_VENDOR_ID_INTEL)
 			continue;
+		/* We don't want to poke around undefined i740 registers */
+		if (is_i740(dev))
+			continue;
 		pci_read_config_dword(dev, 0xfc, &address);
 		if (!address)
 			continue;
-		return 1;
+		opregion = 1;
 	}
-#endif
-	return 0;
+	return opregion;
 }
 
 int acpi_video_register(void)
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index b0d62820ada173fb23066a611532934b926db99d..9e6e1c6eb60a94885f1e9c08038cc8e081f86547 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -440,8 +440,8 @@ static inline int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
 
 #else	/* CONFIG_ACPI */
 
-static int register_acpi_bus_type(struct acpi_bus_type *bus) { return 0; }
-static int unregister_acpi_bus_type(struct acpi_bus_type *bus) { return 0; }
+static inline int register_acpi_bus_type(void *bus) { return 0; }
+static inline int unregister_acpi_bus_type(void *bus) { return 0; }
 
 #endif				/* CONFIG_ACPI */
 
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index ab2f682fd44c6cbc402b4a1ab8cbfd0fa9ce0f2e..16de7ad4850fa553ad72177415a9a56c71ebf3fe 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -73,8 +73,8 @@ int backwards_count;
 char *progname;
 
 int num_cpus;
-cpu_set_t *cpu_mask;
-size_t cpu_mask_size;
+cpu_set_t *cpu_present_set, *cpu_mask;
+size_t cpu_present_setsize, cpu_mask_size;
 
 struct counters {
 	unsigned long long tsc;		/* per thread */
@@ -103,6 +103,12 @@ struct timeval tv_even;
 struct timeval tv_odd;
 struct timeval tv_delta;
 
+int mark_cpu_present(int pkg, int core, int cpu)
+{
+	CPU_SET_S(cpu, cpu_present_setsize, cpu_present_set);
+	return 0;
+}
+
 /*
  * cpu_mask_init(ncpus)
  *
@@ -118,6 +124,18 @@ void cpu_mask_init(int ncpus)
 	}
 	cpu_mask_size = CPU_ALLOC_SIZE(ncpus);
 	CPU_ZERO_S(cpu_mask_size, cpu_mask);
+
+	/*
+	 * Allocate and initialize cpu_present_set
+	 */
+	cpu_present_set = CPU_ALLOC(ncpus);
+	if (cpu_present_set == NULL) {
+		perror("CPU_ALLOC");
+		exit(3);
+	}
+	cpu_present_setsize = CPU_ALLOC_SIZE(ncpus);
+	CPU_ZERO_S(cpu_present_setsize, cpu_present_set);
+	for_all_cpus(mark_cpu_present);
 }
 
 void cpu_mask_uninit()
@@ -125,6 +143,9 @@ void cpu_mask_uninit()
 	CPU_FREE(cpu_mask);
 	cpu_mask = NULL;
 	cpu_mask_size = 0;
+	CPU_FREE(cpu_present_set);
+	cpu_present_set = NULL;
+	cpu_present_setsize = 0;
 }
 
 int cpu_migrate(int cpu)
@@ -912,6 +933,8 @@ int is_snb(unsigned int family, unsigned int model)
 	switch (model) {
 	case 0x2A:
 	case 0x2D:
+	case 0x3A:	/* IVB */
+	case 0x3D:	/* IVB Xeon */
 		return 1;
 	}
 	return 0;
@@ -1047,6 +1070,9 @@ int fork_it(char **argv)
 	int retval;
 	pid_t child_pid;
 	get_counters(cnt_even);
+
+        /* clear affinity side-effect of get_counters() */
+        sched_setaffinity(0, cpu_present_setsize, cpu_present_set);
 	gettimeofday(&tv_even, (struct timezone *)NULL);
 
 	child_pid = fork();