Merge tag 'tty-3.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty fixes from Greg KH:
 "Here are two tty driver fixes for 3.12-rc4.

  One fixes the reported regression in the n_tty code that a number of
  people found recently, and the other one fixes an issue with xen
  consoles that broke in 3.10"

* tag 'tty-3.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  xen/hvc: allow xenboot console to be used again
  tty: Fix pty master read() after slave closes

drivers/tty/hvc/hvc_xen.c

@@ -636,6 +636,7 @@ struct console xenboot_console = {
 	.name		= "xenboot",
 	.write		= xenboot_write_console,
 	.flags		= CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
+	.index		= -1,
 };
 #endif	/* CONFIG_EARLY_PRINTK */
 

drivers/tty/n_tty.c

@@ -2183,9 +2183,14 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 
 		if (!input_available_p(tty, 0)) {
 			if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
+				up_read(&tty->termios_rwsem);
+				tty_flush_to_ldisc(tty);
+				down_read(&tty->termios_rwsem);
+				if (!input_available_p(tty, 0)) {
 					retval = -EIO;
 					break;
 				}
+			} else {
 				if (tty_hung_up_p(file))
 					break;
 				if (!timeout)
@@ -2206,6 +2211,7 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 				down_read(&tty->termios_rwsem);
 				continue;
 			}
+		}
 		__set_current_state(TASK_RUNNING);
 
 		/* Deal with packet mode. */