vt: Don't check KD_GRAPHICS when binding/unbinding

This was introduced in

commit 6db4063c5b72b46e9793b0f141a7a3984ac6facf
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: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 08e303c4208cc763e21ced2593cd131305072447..8fe52989b380155926c6865721e9ba16e2a60685 100644 (file)
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -3204,22 +3204,6 @@ err:
 
 
 #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;