diff --git a/drivers/acpi/tables/tbfadt.c b/drivers/acpi/tables/tbfadt.c
index d2e60a8fa9a58341dc2501c23f71d17ac96fffc3..14661a861c5881100e2914318d4395a7e5c98b8d 100644
--- a/drivers/acpi/tables/tbfadt.c
+++ b/drivers/acpi/tables/tbfadt.c
@@ -286,14 +286,27 @@ static void acpi_tb_convert_fadt(void)
 
 	acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);
 
-	/* Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary */
-
+	/*
+	 * Expand the 32-bit FACS and DSDT addresses to 64-bit as necessary.
+	 * Later code will always use the X 64-bit field. Also, check for an
+	 * address mismatch between the 32-bit and 64-bit address fields
+	 * (FIRMWARE_CTRL/X_FIRMWARE_CTRL, DSDT/X_DSDT) which would indicate
+	 * the presence of two FACS or two DSDT tables.
+	 */
 	if (!acpi_gbl_FADT.Xfacs) {
 		acpi_gbl_FADT.Xfacs = (u64) acpi_gbl_FADT.facs;
+	} else if (acpi_gbl_FADT.facs &&
+		   (acpi_gbl_FADT.Xfacs != (u64) acpi_gbl_FADT.facs)) {
+		ACPI_WARNING((AE_INFO,
+		    "32/64 FACS address mismatch in FADT - two FACS tables!"));
 	}
 
 	if (!acpi_gbl_FADT.Xdsdt) {
 		acpi_gbl_FADT.Xdsdt = (u64) acpi_gbl_FADT.dsdt;
+	} else if (acpi_gbl_FADT.dsdt &&
+		   (acpi_gbl_FADT.Xdsdt != (u64) acpi_gbl_FADT.dsdt)) {
+		ACPI_WARNING((AE_INFO,
+		    "32/64 DSDT address mismatch in FADT - two DSDT tables!"));
 	}
 
 	/*