From: Geert Uytterhoeven Date: Fri, 28 Oct 2016 12:07:47 +0000 (-0500) Subject: tty: serial_core: Fix serial console crash on port shutdown X-Git-Tag: v4.9-rc3~7^2~1 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=4dda864d73079a1eb01fab4ec29b97db150163bf;p=linux.git tty: serial_core: Fix serial console crash on port shutdown The port->console flag is always false, as uart_console() is called before the serial console has been registered. Hence for a serial port used as the console, uart_tty_port_shutdown() will still be called when userspace closes the port, powering it down. This may lead to a system lock up when the serial console driver writes to the serial port's registers. To fix this, move the setting of port->console after the call to uart_configure_port(), which registers the serial console. Fixes: 761ed4a94582ab29 ("tty: serial_core: convert uart_close to use tty_port_close") Reported-by: Niklas Söderlund Signed-off-by: Geert Uytterhoeven Acked-by: Rob Herring Tested-by: Mugunthan V N Tested-by: Niklas Söderlund [robh: rebased on tty-linus] Signed-off-by: Rob Herring Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 664c99aeeca5..ce8899c13af3 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2759,6 +2759,8 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport) uart_configure_port(drv, state, uport); + port->console = uart_console(uport); + num_groups = 2; if (uport->attr_group) num_groups++;