ACPICA: Fix for update of the Global Lock Handle
Fixed a problem where the global lock handle was not properly
updated if a thread that acquired the global lock via
executing AML code then attempted to acquire the lock via the
AcpiAcquireGlobalLock interface.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/events/evmisc.c b/drivers/acpi/events/evmisc.c
index 2d34663..d075062 100644
--- a/drivers/acpi/events/evmisc.c
+++ b/drivers/acpi/events/evmisc.c
@@ -461,6 +461,19 @@
acpi_ev_global_lock_acquired++;
/*
+ * Update the global lock handle and check for wraparound. The handle is
+ * only used for the external global lock interfaces, but it is updated
+ * here to properly handle the case where a single thread may acquire the
+ * lock via both the AML and the acpi_acquire_global_lock interfaces. The
+ * handle is therefore updated on the first acquire from a given thread
+ * regardless of where the acquisition request originated.
+ */
+ acpi_gbl_global_lock_handle++;
+ if (acpi_gbl_global_lock_handle == 0) {
+ acpi_gbl_global_lock_handle = 1;
+ }
+
+ /*
* Make sure that a global lock actually exists. If not, just treat
* the lock as a standard mutex.
*/
diff --git a/drivers/acpi/events/evxface.c b/drivers/acpi/events/evxface.c
index e210aa2..412cae6 100644
--- a/drivers/acpi/events/evxface.c
+++ b/drivers/acpi/events/evxface.c
@@ -782,15 +782,8 @@
acpi_os_get_thread_id());
if (ACPI_SUCCESS(status)) {
- /*
- * If this was the first acquisition of the Global Lock by this thread,
- * create a new handle. Otherwise, return the existing handle.
- */
- if (acpi_gbl_global_lock_mutex->mutex.acquisition_depth == 1) {
- acpi_gbl_global_lock_handle++;
- }
- /* Return the global lock handle */
+ /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
*handle = acpi_gbl_global_lock_handle;
}
