From: Borut Seljak <borut.seljak@t-2.net>
Date: Fri, 7 Jun 2019 10:53:06 +0000 (+0200)
Subject: serial: stm32: fix a recursive locking in stm32_config_rs485
X-Git-Tag: v5.3-rc1~125^2~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=707aeea13a9c85520262e11899d86df3c4b48262;p=thirdparty%2Fkernel%2Flinux.git

serial: stm32: fix a recursive locking in stm32_config_rs485

Remove spin_lock_irqsave in stm32_config_rs485, it cause recursive locking.
Already locked in uart_set_rs485_config.

Fixes: 1bcda09d291081 ("serial: stm32: add support for RS485 hardware control mode")
Signed-off-by: Borut Seljak <borut.seljak@t-2.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 4c217fb35bcb0..7a46d7ba967e4 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -105,9 +105,7 @@ static int stm32_config_rs485(struct uart_port *port,
 	struct stm32_usart_config *cfg = &stm32_port->info->cfg;
 	u32 usartdiv, baud, cr1, cr3;
 	bool over8;
-	unsigned long flags;
 
-	spin_lock_irqsave(&port->lock, flags);
 	stm32_clr_bits(port, ofs->cr1, BIT(cfg->uart_enable_bit));
 
 	port->rs485 = *rs485conf;
@@ -147,7 +145,6 @@ static int stm32_config_rs485(struct uart_port *port,
 	}
 
 	stm32_set_bits(port, ofs->cr1, BIT(cfg->uart_enable_bit));
-	spin_unlock_irqrestore(&port->lock, flags);
 
 	return 0;
 }