diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index cc94af2d578a..a743964c9d22 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2147,8 +2147,7 @@ static void serial8250_THRE_test(struct uart_port *port)
 	if (up->port.flags & UPF_NO_THRE_TEST)
 		return;
 
-	if (port->irqflags & IRQF_SHARED)
-		disable_irq_nosync(port->irq);
+	disable_irq(port->irq);
 
 	/*
 	 * Test for UARTs that do not reassert THRE when the transmitter is idle and the interrupt
@@ -2170,8 +2169,7 @@ static void serial8250_THRE_test(struct uart_port *port)
 		serial_port_out(port, UART_IER, 0);
 	}
 
-	if (port->irqflags & IRQF_SHARED)
-		enable_irq(port->irq);
+	enable_irq(port->irq);
 
 	/*
 	 * If the interrupt is not reasserted, or we otherwise don't trust the iir, setup a timer to