From 82776f6c75a90e1d2103e689b84a689de8f1aa02 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 18 Oct 2020 09:42:04 +0100 Subject: tty: serial: 21285: fix lockup on open Commit 293f89959483 ("tty: serial: 21285: stop using the unused[] variable from struct uart_port") introduced a bug which stops the transmit interrupt being disabled when there are no characters to transmit - disabling the transmit interrupt at the interrupt controller is the only way to stop an interrupt storm. If this interrupt is not disabled when there are no transmit characters, we end up with an interrupt storm which prevents the machine making forward progress. Fixes: 293f89959483 ("tty: serial: 21285: stop using the unused[] variable from struct uart_port") Signed-off-by: Russell King Cc: stable Link: https://lore.kernel.org/r/E1kU4GS-0006lE-OO@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/21285.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/21285.c b/drivers/tty/serial/21285.c index 718e010fcb04..09baef4ccc39 100644 --- a/drivers/tty/serial/21285.c +++ b/drivers/tty/serial/21285.c @@ -50,25 +50,25 @@ static const char serial21285_name[] = "Footbridge UART"; static bool is_enabled(struct uart_port *port, int bit) { - unsigned long private_data = (unsigned long)port->private_data; + unsigned long *private_data = (unsigned long *)&port->private_data; - if (test_bit(bit, &private_data)) + if (test_bit(bit, private_data)) return true; return false; } static void enable(struct uart_port *port, int bit) { - unsigned long private_data = (unsigned long)port->private_data; + unsigned long *private_data = (unsigned long *)&port->private_data; - set_bit(bit, &private_data); + set_bit(bit, private_data); } static void disable(struct uart_port *port, int bit) { - unsigned long private_data = (unsigned long)port->private_data; + unsigned long *private_data = (unsigned long *)&port->private_data; - clear_bit(bit, &private_data); + clear_bit(bit, private_data); } #define is_tx_enabled(port) is_enabled(port, tx_enabled_bit) -- cgit v1.2.3