vt: Don't check KD_GRAPHICS when binding/unbinding

This was introduced in

commit 6db4063c
Author: Antonino A. Daplas <adaplas@gmail.com>
Date:   Mon Jun 26 00:27:12 2006 -0700

    [PATCH] VT binding: Add sysfs control to the VT layer

with the justification

    "In addition, if any of the consoles are in KD_GRAPHICS mode, binding and
    unbinding will not succeed.  KD_GRAPHICS mode usually indicates that the
    underlying console hardware is used for other purposes other than displaying
    text (ie X).  This feature should prevent binding/unbinding from interfering
    with a graphics application using the VT."

I think we should lift this artificial restriction though:
- KD_GRAPHICS doesn't get cleaned up automatically, which means it's
  easy to have terminals stuck in KD_GRAPHICS when hacking around on
  X.
- X doesn't really care, especially with drm where kms already blocks
  fbdev (and hence fbcon) when there's an active compositor.
- This is a root-only interface with a separate .config option and
  it's possible to hang your machine already anyway if you
  unload/reload drivers and don't know what you're doing.

With this patch i915.ko module reloading works again reliably,
something in the recent fedora upgrades broke things.

Cc: Antonino A. Daplas <adaplas@gmail.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Acked-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/vt.c

@@ -3204,22 +3204,6 @@ static int do_bind_con_driver(const struct consw *csw, int first, int last,
 
 
 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
-static int con_is_graphics(const struct consw *csw, int first, int last)
-{
-	int i, retval = 0;
-
-	for (i = first; i <= last; i++) {
-		struct vc_data *vc = vc_cons[i].d;
-
-		if (vc && vc->vc_mode == KD_GRAPHICS) {
-			retval = 1;
-			break;
-		}
-	}
-
-	return retval;
-}
-
 /* unlocked version of unbind_con_driver() */
 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
 {
@@ -3305,8 +3289,7 @@ static int vt_bind(struct con_driver *con)
 	const struct consw *defcsw = NULL, *csw = NULL;
 	int i, more = 1, first = -1, last = -1, deflt = 0;
 
- 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE) ||
-	    con_is_graphics(con->con, con->first, con->last))
+ 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
 		goto err;
 
 	csw = con->con;
@@ -3357,8 +3340,7 @@ static int vt_unbind(struct con_driver *con)
 	int i, more = 1, first = -1, last = -1, deflt = 0;
 	int ret;
 
- 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE) ||
-	    con_is_graphics(con->con, con->first, con->last))
+ 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
 		goto err;
 
 	csw = con->con;