If the call to uart_add_one_port() in serial8250_register_8250_port()
fails, a half-initialized entry in the serial_8250ports[] array is left
behind.
A subsequent reprobe of the same serial port causes that entry to be
reused. Because uart->port.dev is set, uart_remove_one_port() is called
for the half-initialized entry and bails out with an error message:
bcm2835-aux-uart 3f215040.serial: Removing wrong port: (null) != (ptrval)
The same happens on failure of mctrl_gpio_init() since commit
4a96895f74c9 ("tty/serial/8250: use mctrl_gpio helpers").
Fix by zeroing the uart->port.dev pointer in the probe error path.
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v2.6.10+
---
drivers/tty/serial/8250/8250_core.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 45d9117cab68..14abade589da 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1040,7 +1040,7 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
gpios = mctrl_gpio_init(&uart->port, 0);
if (IS_ERR(gpios)) {
ret = PTR_ERR(gpios);
- goto out_unlock;
+ goto err;
} else {
uart->gpios = gpios;
}
@@ -1089,7 +1089,9 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
serial8250_apply_quirks(uart);
ret = uart_add_one_port(&serial8250_reg,
&uart->port);
- if (ret == 0)
+ if (ret)
+ goto err;
+ else
ret = uart->port.line;
} else {
dev_info(uart->port.dev,
@@ -1112,10 +1114,14 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
}
}
-out_unlock:
mutex_unlock(&serial_mutex);
return ret;
+
+err:
+ uart->port.dev = NULL;
+ mutex_unlock(&serial_mutex);
+ return ret;
}
EXPORT_SYMBOL(serial8250_register_8250_port);
--
2.26.2
