Merge tag 'tty-4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver fix from Greg KH:
 "Here's a single 8250 serial driver that fixes a reported deadlock with
  the serial console and the tty driver.

  It's been in linux-next for a while now"

* tag 'tty-4.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250_dw: Fix deadlock in LCR workaround

1 files changed, 12 insertions, 3 deletions

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 2ab229ddee38..6ae5b8560e4d 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -119,7 +119,10 @@ static void dw8250_serial_out(struct uart_port *p, int offset, int value)
                         dw8250_force_idle(p);
                         writeb(value, p->membase + (UART_LCR << p->regshift));
                 }
-                dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+                /*
+                 * FIXME: this deadlocks if port->lock is already held
+                 * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+                 */
         }
 }
 
@@ -163,7 +166,10 @@ static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
                         __raw_writeq(value & 0xff,
                                      p->membase + (UART_LCR << p->regshift));
                 }
-                dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+                /*
+                 * FIXME: this deadlocks if port->lock is already held
+                 * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+                 */
         }
 }
 #endif /* CONFIG_64BIT */
@@ -187,7 +193,10 @@ static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
                         dw8250_force_idle(p);
                         writel(value, p->membase + (UART_LCR << p->regshift));
                 }
-                dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+                /*
+                 * FIXME: this deadlocks if port->lock is already held
+                 * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+                 */
         }
 }