1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c
index 0489a7d1d42c..313507accf18 100644
--- a/drivers/acpi/sleep/main.c
+++ b/drivers/acpi/sleep/main.c
@@ -283,6 +283,15 @@ static struct platform_suspend_ops acpi_suspend_ops_old = {
 #endif /* CONFIG_SUSPEND */
 
 #ifdef CONFIG_HIBERNATION
+static unsigned long s4_hardware_signature;
+static struct acpi_table_facs *facs;
+static bool nosigcheck;
+
+void __init acpi_no_s4_hw_signature(void)
+{
+        nosigcheck = true;
+}
+
 static int acpi_hibernation_begin(void)
 {
         acpi_target_sleep_state = ACPI_STATE_S4;
@@ -316,6 +325,12 @@ static void acpi_hibernation_leave(void)
         acpi_enable();
         /* Reprogram control registers and execute _BFS */
         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
+        /* Check the hardware signature */
+        if (facs && s4_hardware_signature != facs->hardware_signature) {
+                printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
+                        "cannot resume!\n");
+                panic("ACPI S4 hardware signature mismatch");
+        }
 }
 
 static void acpi_pm_enable_gpes(void)
@@ -544,6 +559,13 @@ int __init acpi_sleep_init(void)
                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
                 sleep_states[ACPI_STATE_S4] = 1;
                 printk(" S4");
+                if (!nosigcheck) {
+                        acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
+                                (struct acpi_table_header **)&facs);
+                        if (facs)
+                                s4_hardware_signature =
+                                        facs->hardware_signature;
+                }
         }
 #endif
         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);