Commit a157270f authored by Ahmed S. Darwish's avatar Ahmed S. Darwish Committed by Greg Kroah-Hartman
Browse files

serial: core: Remove BUG_ON(in_interrupt()) check 



The usage of in_interrupt() in drivers is phased out for various
reasons.

In both exported functions where BUG_ON(in_interrupt()) is invoked,
there is a mutex_lock() afterwards. mutex_lock() contains a
might_sleep() which will already trigger a stack trace if the target
functions is called from atomic context.

Remove the BUG_ON() and add a "Context: " in the kernel-doc instead.

Signed-off-by: default avatarAhmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20210208181615.381861-3-bigeasy@linutronix.de


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 151db8c0

drivers/tty/serial/serial_core.c

+4 −4
Original line number Diff line number Diff line
@@ -2848,6 +2848,8 @@ static const struct attribute_group tty_dev_attr_group = { 
 *	@drv: pointer to the uart low level driver structure for this port

 *	@uport: uart port structure to use for this port.

 *

 *	Context: task context, might sleep

 *

 *	This allows the driver to register its own uart_port structure

 *	with the core driver.  The main purpose is to allow the low

 *	level uart drivers to expand uart_port, rather than having yet
@@ -2861,8 +2863,6 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) 
	struct device *tty_dev;

	int num_groups;



	BUG_ON(in_interrupt());



	if (uport->line >= drv->nr)

		return -EINVAL;
@@ -2951,6 +2951,8 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) 
 *	@drv: pointer to the uart low level driver structure for this port

 *	@uport: uart port structure for this port

 *

 *	Context: task context, might sleep

 *

 *	This unhooks (and hangs up) the specified port structure from the

 *	core driver.  No further calls will be made to the low-level code

 *	for this port.
@@ -2963,8 +2965,6 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport) 
	struct tty_struct *tty;

	int ret = 0;



	BUG_ON(in_interrupt());



	mutex_lock(&port_mutex);



	/*