Re: [PATCH 05/15] serial: sc16is7xx: use guards for simple mutex locks

From: Jiri Slaby

Date: Mon Sep 29 2025 - 02:09:15 EST


On 24. 09. 25, 17:37, Hugo Villeneuve wrote:
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
...
@@ -829,9 +827,6 @@ static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
break;
}
-out_port_irq:
- mutex_unlock(&one->lock);
-
return rc;

No need for rc now AFAICT.

}
@@ -874,9 +869,8 @@ static void sc16is7xx_tx_proc(struct kthread_work *ws)
(port->rs485.delay_rts_before_send > 0))
msleep(port->rs485.delay_rts_before_send);
- mutex_lock(&one->lock);
+ guard(mutex)(&one->lock);
sc16is7xx_handle_tx(port);
- mutex_unlock(&one->lock);
}
static void sc16is7xx_reconf_rs485(struct uart_port *port)
@@ -943,9 +937,8 @@ static void sc16is7xx_ms_proc(struct kthread_work *ws)
struct sc16is7xx_port *s = dev_get_drvdata(one->port.dev);
if (one->port.state) {
- mutex_lock(&one->lock);
+ guard(mutex)(&one->lock);
sc16is7xx_update_mlines(one);
- mutex_unlock(&one->lock);
kthread_queue_delayed_work(&s->kworker, &one->ms_work, HZ);

Now the lock is held till here. R U sure it is OK?

thanks,
--
js
suse labs