[PATCH] Remove BUG_ON from n_tty_read()

[Stanislav Kozina <skozina@redhat.com>]

Change the BUG_ON to WARN_ON and return in case of tty->read_buf==NULL

Signed-off-by: Stanislav Kozina <skozina@redhat.com>
---
  drivers/tty/n_tty.c |    5 ++++-
  1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index df21f39..39c6202 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1728,7 +1728,10 @@ static ssize_t n_tty_read(struct tty_struct *tty, 
struct file *file,

  do_it_again:

-	BUG_ON(!tty->read_buf);
+	if (!tty->read_buf) {
+		WARN_ON(!tty->read_buf);
+		return -EAGAIN;
+	}

  	c = job_control(tty, file);
  	if (c < 0)
-- 
1.7.1