This is a note to let you know that I've just added the patch titled serial: core: fix crash in uart_suspend_port to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: serial-core-fix-crash-in-uart_suspend_port.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 88e2582e90bb89fe895ff0dceeb5d5ab65d07997 Mon Sep 17 00:00:00 2001 From: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Date: Thu, 11 May 2017 12:56:14 +0200 Subject: serial: core: fix crash in uart_suspend_port From: Lucas Stach <l.stach@xxxxxxxxxxxxxx> commit 88e2582e90bb89fe895ff0dceeb5d5ab65d07997 upstream. With serdev we might end up with serial ports that have no cdev exported to userspace, as they are used as the bus interface to other devices. In that case serial_match_port() won't be able to find a matching tty_dev. Skip the irq wakeup enabling in that case, as serdev will make sure to keep the port active, as long as there are devices depending on it. Fixes: 8ee3fde04758 (tty_port: register tty ports with serdev bus) Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/serial_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2083,7 +2083,7 @@ int uart_suspend_port(struct uart_driver mutex_lock(&port->mutex); tty_dev = device_find_child(uport->dev, &match, serial_match_port); - if (device_may_wakeup(tty_dev)) { + if (tty_dev && device_may_wakeup(tty_dev)) { if (!enable_irq_wake(uport->irq)) uport->irq_wake = 1; put_device(tty_dev); Patches currently in stable-queue which might be from l.stach@xxxxxxxxxxxxxx are queue-4.11/serial-core-fix-crash-in-uart_suspend_port.patch