Commit 452b9b24 authored by John Ogness's avatar John Ogness Committed by Petr Mladek
Browse files

serial_core: replace uart_console_enabled() with uart_console_registered() 



All users of uart_console_enabled() really want to know if a console
is registered. It is not reliable to check for CON_ENABLED in order
to identify if a console is registered. Use console_is_registered()
instead.

A _locked() variant is provided because uart_set_options() is always
called with the console_list_lock held and must check if a console
is registered in order to synchronize with kgdboc.

Signed-off-by: default avatarJohn Ogness <john.ogness@linutronix.de>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-23-john.ogness@linutronix.de
parent 1fd4224a

drivers/tty/serial/8250/8250_core.c

+1 −1
Original line number Diff line number Diff line
@@ -565,7 +565,7 @@ serial8250_register_ports(struct uart_driver *drv, struct device *dev) 


		up->port.dev = dev;



		if (uart_console_enabled(&up->port))

		if (uart_console_registered(&up->port))

			pm_runtime_get_sync(up->port.dev);



		serial8250_apply_quirks(up);

drivers/tty/serial/pic32_uart.c

+1 −1
Original line number Diff line number Diff line
@@ -919,7 +919,7 @@ static int pic32_uart_probe(struct platform_device *pdev) 
	}



#ifdef CONFIG_SERIAL_PIC32_CONSOLE

	if (uart_console_enabled(port)) {

	if (uart_console_registered(port)) {

		/* The peripheral clock has been enabled by console_setup,

		 * so disable it till the port is used.

		 */

drivers/tty/serial/serial_core.c

+7 −7
Original line number Diff line number Diff line
@@ -2223,11 +2223,11 @@ uart_set_options(struct uart_port *port, struct console *co, 
	/*

	 * Ensure that the serial-console lock is initialised early.

	 *

	 * Note that the console-enabled check is needed because of kgdboc,

	 * which can end up calling uart_set_options() for an already enabled

	 * Note that the console-registered check is needed because

	 * kgdboc can call uart_set_options() for an already registered

	 * console via tty_find_polling_driver() and uart_poll_init().

	 */

	if (!uart_console_enabled(port) && !port->console_reinit)

	if (!uart_console_registered_locked(port) && !port->console_reinit)

		uart_port_spin_lock_init(port);



	memset(&termios, 0, sizeof(struct ktermios));
@@ -2573,7 +2573,7 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state, 
		 * successfully registered yet, try to re-register it.

		 * It may be that the port was not available.

		 */

		if (port->cons && !(port->cons->flags & CON_ENABLED))

		if (port->cons && !console_is_registered(port->cons))

			register_console(port->cons);



		/*
@@ -2956,7 +2956,7 @@ static ssize_t console_show(struct device *dev, 
	mutex_lock(&port->mutex);

	uport = uart_port_check(state);

	if (uport)

		console = uart_console_enabled(uport);

		console = uart_console_registered(uport);

	mutex_unlock(&port->mutex);



	return sprintf(buf, "%c\n", console ? 'Y' : 'N');
@@ -2978,7 +2978,7 @@ static ssize_t console_store(struct device *dev, 
	mutex_lock(&port->mutex);

	uport = uart_port_check(state);

	if (uport) {

		oldconsole = uart_console_enabled(uport);

		oldconsole = uart_console_registered(uport);

		if (oldconsole && !newconsole) {

			ret = unregister_console(uport->cons);

		} else if (!oldconsole && newconsole) {
@@ -3086,7 +3086,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) 
	 * If this port is in use as a console then the spinlock is already

	 * initialised.

	 */

	if (!uart_console_enabled(uport))

	if (!uart_console_registered(uport))

		uart_port_spin_lock_init(uport);



	if (uport->cons && uport->dev)

include/linux/serial_core.h

+8 −2
Original line number Diff line number Diff line
@@ -743,9 +743,15 @@ static const bool earlycon_acpi_spcr_enable EARLYCON_USED_OR_UNUSED; 
static inline int setup_earlycon(char *buf) { return 0; }

#endif



static inline bool uart_console_enabled(struct uart_port *port)

/* Variant of uart_console_registered() when the console_list_lock is held. */

static inline bool uart_console_registered_locked(struct uart_port *port)

{

	return uart_console(port) && (port->cons->flags & CON_ENABLED);

	return uart_console(port) && console_is_registered_locked(port->cons);

}



static inline bool uart_console_registered(struct uart_port *port)

{

	return uart_console(port) && console_is_registered(port->cons);

}



struct uart_port *uart_get_console(struct uart_port *ports, int nr,