drm/nouveau: fix for disabled fbdev emulation

commit 52dfcc5ccfbb6697ac3cac7f7ff1e712760e1216 upstream.

Hello,

after this commit:

commit f045f459d925138fe7d6193a8c86406bda7e49da
Author: Ben Skeggs <bskeggs@redhat.com>
Date:   Thu Jun 2 12:23:31 2016 +1000
    drm/nouveau/fbcon: fix out-of-bounds memory accesses

kernel started to oops when loading nouveau module when using GTX 780 Ti
video adapter. This patch fixes the problem.

Bug report: https://bugzilla.kernel.org/show_bug.cgi?id=120591

Signed-off-by: Dmitrii Tcvetkov <demfloro@demfloro.ru>
Suggested-by: Ilia Mirkin <imirkin@alum.mit.edu>
Fixes: f045f459d925 ("nouveau_fbcon_init()")
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
index bd89c8656c9313cffb440196bb9e2fdd0a5292d7..e40a1b07a01471c301da6d1cd598628421033283 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
@@ -557,7 +557,8 @@ nouveau_fbcon_init(struct drm_device *dev)
        if (ret)
                goto fini;
 
-       fbcon->helper.fbdev->pixmap.buf_align = 4;
+       if (fbcon->helper.fbdev)
+               fbcon->helper.fbdev->pixmap.buf_align = 4;
        return 0;
 
 fini: