+> echo "-" > /sys/kernel/debug/s390dbf/dasd/level
+
+It is also possible to deactivate the debug feature globally for every
+debug log. You can change the behavior using 2 sysctl parameters in
+/proc/sys/s390dbf:
+There are currently 2 possible triggers, which stop the debug feature
+globally. The first possibility is to use the "debug_active" sysctl. If
+set to 1 the debug feature is running. If "debug_active" is set to 0 the
+debug feature is turned off.
+The second trigger which stops the debug feature is a kernel oops.
+That prevents the debug feature from overwriting debug information that
+happened before the oops. After an oops you can reactivate the debug feature
+by piping 1 to /proc/sys/s390dbf/debug_active. Nevertheless, its not
+suggested to use an oopsed kernel in a production environment.
+If you want to disallow the deactivation of the debug feature, you can use
+the "debug_stoppable" sysctl. If you set "debug_stoppable" to 0 the debug
+feature cannot be stopped. If the debug feature is already stopped, it
+will stay deactivated.