3 files changed, 8 insertions, 15 deletions

diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c
index 1bd28450ca40..a764bf99743b 100644
--- a/drivers/tty/serial/mrst_max3110.c
+++ b/drivers/tty/serial/mrst_max3110.c
@@ -421,7 +421,6 @@ static int max3110_main_thread(void *_max)
         int ret = 0;
         struct circ_buf *xmit = &max->con_xmit;
 
-        init_waitqueue_head(wq);
         pr_info(PR_FMT "start main thread\n");
 
         do {
@@ -823,7 +822,7 @@ static int __devinit serial_m3110_probe(struct spi_device *spi)
         res = RC_TAG;
         ret = max3110_write_then_read(max, (u8 *)&res, (u8 *)&res, 2, 0);
         if (ret < 0 || res == 0 || res == 0xffff) {
-                printk(KERN_ERR "MAX3111 deemed not present (conf reg %04x)",
+                dev_dbg(&spi->dev, "MAX3111 deemed not present (conf reg %04x)",
                                                                         res);
                 ret = -ENODEV;
                 goto err_get_page;
@@ -838,6 +837,8 @@ static int __devinit serial_m3110_probe(struct spi_device *spi)
         max->con_xmit.head = 0;
         max->con_xmit.tail = 0;
 
+        init_waitqueue_head(&max->wq);
+
         max->main_thread = kthread_run(max3110_main_thread,
                                         max, "max3110_main");
         if (IS_ERR(max->main_thread)) {
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index f2cb7503fcb2..465210930890 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -1397,6 +1397,7 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
         int fifosize, base_baud;
         int port_type;
         struct pch_uart_driver_data *board;
+        const char *board_name;
 
         board = &drv_dat[id->driver_data];
         port_type = board->port_type;
@@ -1412,7 +1413,8 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
         base_baud = 1843200; /* 1.8432MHz */
 
         /* quirk for CM-iTC board */
-        if (strstr(dmi_get_system_info(DMI_BOARD_NAME), "CM-iTC"))
+        board_name = dmi_get_system_info(DMI_BOARD_NAME);
+        if (board_name && strstr(board_name, "CM-iTC"))
                 base_baud = 192000000; /* 192.0MHz */
 
         switch (port_type) {
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index f1a7918d71aa..6c9b7cd6778a 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -413,8 +413,7 @@ static void flush_to_ldisc(struct work_struct *work)
         spin_lock_irqsave(&tty->buf.lock, flags);
 
         if (!test_and_set_bit(TTY_FLUSHING, &tty->flags)) {
-                struct tty_buffer *head, *tail = tty->buf.tail;
-                int seen_tail = 0;
+                struct tty_buffer *head;
                 while ((head = tty->buf.head) != NULL) {
                         int count;
                         char *char_buf;
@@ -424,15 +423,6 @@ static void flush_to_ldisc(struct work_struct *work)
                         if (!count) {
                                 if (head->next == NULL)
                                         break;
-                                /*
-                                  There's a possibility tty might get new buffer
-                                  added during the unlock window below. We could
-                                  end up spinning in here forever hogging the CPU
-                                  completely. To avoid this let's have a rest each
-                                  time we processed the tail buffer.
-                                */
-                                if (tail == head)
-                                        seen_tail = 1;
                                 tty->buf.head = head->next;
                                 tty_buffer_free(tty, head);
                                 continue;
@@ -442,7 +432,7 @@ static void flush_to_ldisc(struct work_struct *work)
                            line discipline as we want to empty the queue */
                         if (test_bit(TTY_FLUSHPENDING, &tty->flags))
                                 break;
-                        if (!tty->receive_room || seen_tail)
+                        if (!tty->receive_room)
                                 break;
                         if (count > tty->receive_room)
                                 count = tty->receive_room;