tree 3afe1620aba69b36ab45ff9fe26e368e452f25eb
parent 72a3c0e4e6624a77ee6eee0903f209185fe20647
author Peter Hurley <peter@hurleysoftware.com> 1419953965 -0500
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1420839962 -0800

tty: Prevent hw state corruption in exclusive mode reopen

Exclusive mode ttys (TTY_EXCLUSIVE) do not allow further reopens;
fail the condition before associating the file pointer and calling
the driver open() method.

Prevents DTR programming when the tty is already in exclusive mode.

Reported-by: Shreyas Bethur <shreyas.bethur@ni.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Shreyas Bethur <shreyas.bethur@ni.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>