diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index 3780994..08d62c9 100644
--- a/drivers/platform/x86/dell-laptop.c
+++ b/drivers/platform/x86/dell-laptop.c
@@ -22,6 +22,7 @@
 #include <linux/rfkill.h>
 #include <linux/power_supply.h>
 #include <linux/acpi.h>
+#include <linux/mm.h>
 #include "../../firmware/dcdbas.h"
 
 #define BRIGHTNESS_TOKEN 0x7d
@@ -82,6 +83,20 @@ static const struct dmi_system_id __initdata dell_device_table[] = {
 	{ }
 };
 
+static struct calling_interface_buffer *buffer;
+DEFINE_MUTEX(buffer_mutex);
+
+static void get_buffer(void)
+{
+	mutex_lock(&buffer_mutex);
+	memset(buffer, 0, sizeof(struct calling_interface_buffer));
+}
+
+static void release_buffer(void)
+{
+	mutex_unlock(&buffer_mutex);
+}
+
 static void __init parse_da_table(const struct dmi_header *dm)
 {
 	/* Final token is a terminator, so we don't want to copy it */
@@ -184,26 +199,26 @@ dell_send_request(struct calling_interface_buffer *buffer, int class,
 
 static int dell_rfkill_set(void *data, bool blocked)
 {
-	struct calling_interface_buffer buffer;
 	int disable = blocked ? 1 : 0;
 	unsigned long radio = (unsigned long)data;
 
-	memset(&buffer, 0, sizeof(struct calling_interface_buffer));
-	buffer.input[0] = (1 | (radio<<8) | (disable << 16));
-	dell_send_request(&buffer, 17, 11);
+	get_buffer();
+	buffer->input[0] = (1 | (radio<<8) | (disable << 16));
+	dell_send_request(buffer, 17, 11);
+	release_buffer();
 
 	return 0;
 }
 
 static void dell_rfkill_query(struct rfkill *rfkill, void *data)
 {
-	struct calling_interface_buffer buffer;
 	int status;
 	int bit = (unsigned long)data + 16;
 
-	memset(&buffer, 0, sizeof(struct calling_interface_buffer));
-	dell_send_request(&buffer, 17, 11);
-	status = buffer.output[1];
+	get_buffer();
+	dell_send_request(buffer, 17, 11);
+	status = buffer->output[1];
+	release_buffer();
 
 	rfkill_set_sw_state(rfkill, !!(status & BIT(bit)));
 	rfkill_set_hw_state(rfkill, !(status & BIT(16)));
@@ -298,39 +313,45 @@ static void dell_cleanup_rfkill(void)
 
 static int dell_send_intensity(struct backlight_device *bd)
 {
-	struct calling_interface_buffer buffer;
 
-	memset(&buffer, 0, sizeof(struct calling_interface_buffer));
-	buffer.input[0] = find_token_location(BRIGHTNESS_TOKEN);
-	buffer.input[1] = bd->props.brightness;
+	get_buffer();
+	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
+	buffer->input[1] = bd->props.brightness;
 
-	if (buffer.input[0] == -1)
+	if (buffer->input[0] == -1) {
+		release_buffer();
 		return -ENODEV;
+	}
 
 	if (power_supply_is_system_supplied() > 0)
-		dell_send_request(&buffer, 1, 2);
+		dell_send_request(buffer, 1, 2);
 	else
-		dell_send_request(&buffer, 1, 1);
+		dell_send_request(buffer, 1, 1);
 
+	release_buffer();
 	return 0;
 }
 
 static int dell_get_intensity(struct backlight_device *bd)
 {
-	struct calling_interface_buffer buffer;
+	int ret;
 
-	memset(&buffer, 0, sizeof(struct calling_interface_buffer));
-	buffer.input[0] = find_token_location(BRIGHTNESS_TOKEN);
+	get_buffer();
+	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
 
-	if (buffer.input[0] == -1)
+	if (buffer->input[0] == -1) {
+		release_buffer();
 		return -ENODEV;
+	}
 
 	if (power_supply_is_system_supplied() > 0)
-		dell_send_request(&buffer, 0, 2);
+		dell_send_request(buffer, 0, 2);
 	else
-		dell_send_request(&buffer, 0, 1);
+		dell_send_request(buffer, 0, 1);
 
-	return buffer.output[1];
+	ret = buffer->output[1];
+	release_buffer();
+	return ret;
 }
 
 static struct backlight_ops dell_ops = {
@@ -340,9 +361,9 @@ static struct backlight_ops dell_ops = {
 
 static int __init dell_init(void)
 {
-	struct calling_interface_buffer buffer;
 	int max_intensity = 0;
 	int ret;
+	struct page *bufferpage;
 
 	if (!dmi_check_system(dell_device_table))
 		return -ENODEV;
@@ -366,6 +387,15 @@ static int __init dell_init(void)
 	if (ret)
 		goto fail_platform_device2;
 
+	/*
+	 * Allocate buffer below 4GB for SMI data--only 32-bit physical addr
+	 * is passed to SMI handler.
+	 */
+	if (!(bufferpage = alloc_page(GFP_KERNEL | GFP_DMA32)))
+		return -ENOMEM;
+	buffer = page_address(bufferpage);
+	mutex_init(&buffer_mutex);
+
 	ret = dell_setup_rfkill();
 
 	if (ret) {
@@ -381,13 +411,14 @@ static int __init dell_init(void)
 		return 0;
 #endif
 
-	memset(&buffer, 0, sizeof(struct calling_interface_buffer));
-	buffer.input[0] = find_token_location(BRIGHTNESS_TOKEN);
+	get_buffer();
+	buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
 
-	if (buffer.input[0] != -1) {
-		dell_send_request(&buffer, 0, 2);
-		max_intensity = buffer.output[3];
+	if (buffer->input[0] != -1) {
+		dell_send_request(buffer, 0, 2);
+		max_intensity = buffer->output[3];
 	}
+	release_buffer();
 
 	if (max_intensity) {
 		dell_backlight_device = backlight_device_register(
@@ -419,6 +450,7 @@ fail_platform_device1:
 	platform_driver_unregister(&platform_driver);
 fail_platform_driver:
 	kfree(da_tokens);
+	free_page(buffer);
 	return ret;
 }
 
@@ -426,6 +458,7 @@ static void __exit dell_exit(void)
 {
 	backlight_device_unregister(dell_backlight_device);
 	dell_cleanup_rfkill();
+	free_page(buffer);
 }
 
 module_init(dell_init);
