1 files changed, 18 insertions, 2 deletions

diff --git a/sys/kern/tty_cons.c b/sys/kern/tty_cons.c
index 784fecad98e2..9aa2c23386d6 100644
--- a/sys/kern/tty_cons.c
+++ b/sys/kern/tty_cons.c
@@ -58,6 +58,7 @@ static	d_read_t	cnread;
 static	d_write_t	cnwrite;
 static	d_ioctl_t	cnioctl;
 static	d_poll_t	cnpoll;
+static	d_kqfilter_t	cnkqfilter;
 
 #define	CDEV_MAJOR	0
 static struct cdevsw cn_cdevsw = {
@@ -73,8 +74,9 @@ static struct cdevsw cn_cdevsw = {
 	/* maj */	CDEV_MAJOR,
 	/* dump */	nodump,
 	/* psize */	nopsize,
-	/* flags */	D_TTY,
-	/* bmaj */	-1
+	/* flags */	D_TTY | D_KQFILTER,
+	/* bmaj */	-1,
+	/* kqfilter */	cnkqfilter,
 };
 
 static dev_t	cn_dev_t; 	/* seems to be never really used */
@@ -398,6 +400,20 @@ cnpoll(dev, events, p)
 	return ((*devsw(dev)->d_poll)(dev, events, p));
 }
 
+static int
+cnkqfilter(dev, kn)
+	dev_t dev;
+	struct knote *kn;
+{
+	if ((cn_tab == NULL) || cn_mute)
+		return (1);
+
+	dev = cn_tab->cn_dev;
+	if (devsw(dev)->d_flags & D_KQFILTER)
+		return ((*devsw(dev)->d_kqfilter)(dev, kn));
+	return (1);
+}
+
 int
 cngetc()
 {