Merge branch 'bugzilla-13041' into release

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / acpi / sleep.c

diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index d060e6fd7fd5d092929bb18ff789d24b12be7e65..01574a06653482a080e21973e44e535824666876 100644 (file)
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -713,6 +713,32 @@ static void acpi_power_off(void)
        acpi_enter_sleep_state(ACPI_STATE_S5);
 }
 
+/*
+ * ACPI 2.0 created the optional _GTS and _BFS,
+ * but industry adoption has been neither rapid nor broad.
+ *
+ * Linux gets into trouble when it executes poorly validated
+ * paths through the BIOS, so disable _GTS and _BFS by default,
+ * but do speak up and offer the option to enable them.
+ */
+void __init acpi_gts_bfs_check(void)
+{
+       acpi_handle dummy;
+
+       if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
+       {
+               printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
+               printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
+                       "please notify linux-acpi@vger.kernel.org\n");
+       }
+       if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
+       {
+               printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
+               printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
+                       "please notify linux-acpi@vger.kernel.org\n");
+       }
+}
+
 int __init acpi_sleep_init(void)
 {
        acpi_status status;
@@ -771,5 +797,6 @@ int __init acpi_sleep_init(void)
         * object can also be evaluated when the system enters S5.
         */
        register_reboot_notifier(&tts_notifier);
+       acpi_gts_bfs_check();
        return 0;
 }