From d9abf6e4f67279f0ea926e6beef7baa9661dce75 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Wed, 18 Nov 2009 14:12:58 +0000 Subject: tty_port: handle the nonblocking open of a dead port corner case commit 8627b96dd80dca440d91fbb1ec733be25912d0dd upstream. Some drivers allow O_NDELAY of a dead port (eg for setserial to work). In that situation we must not try to raise the carrier. Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/tty_port.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c index 6db51f37e2c8..c0ff7eeafbb2 100644 --- a/drivers/char/tty_port.c +++ b/drivers/char/tty_port.c @@ -217,8 +217,11 @@ int tty_port_block_til_ready(struct tty_port *port, /* if non-blocking mode is set we can pass directly to open unless the port has just hung up or is in another error state */ - if ((filp->f_flags & O_NONBLOCK) || - (tty->flags & (1 << TTY_IO_ERROR))) { + if (tty->flags & (1 << TTY_IO_ERROR)) { + port->flags |= ASYNC_NORMAL_ACTIVE; + return 0; + } + if (filp->f_flags & O_NONBLOCK) { /* Indicate we are open */ if (tty->termios->c_cflag & CBAUD) tty_port_raise_dtr_rts(port); -- cgit v1.2.3