Commit 7da4b8b7 authored May 03, 2016 by Peter Hurley Committed by Greg Kroah-Hartman May 03, 2016

serial: core: Fix port mutex assert if lockdep disabled



commit 4047b371 ("serial: core: Prevent unsafe uart port access,
part 1") added lockdep assertion for port mutex but fails to check
if debug_locks has disabled lockdep (so lock state is no longer
reliable).

Use lockdep_assert_held() instead, which properly checks lockdep
state as well.

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 6550be9f

drivers/tty/serial/serial_core.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -95,9 +95,7 @@ static inline void uart_port_deref(struct uart_port *uport)

		static inline struct uart_port uart_port_check(struct uart_state state)
		{
		#ifdef CONFIG_LOCKDEP
		WARN_ON(!lockdep_is_held(&state->port.mutex));
		#endif
		lockdep_assert_held(&state->port.mutex);
		return state->uart_port;
		}