The tty may be closed already when the read/write callbacks are called.
This patch checks that the ttys still exist before waking them up.
Signed-off-by: NOlivier Blin <blino@mandriva.com>
Acked-by: NAlan Cox <alan@redhat.com>
Cc: Jari Tenhunen <jari.tenhunen@iki.fi>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>