drm: fixup drm bufs being just under the EOM
If the mapping was just under the end of memory it would fail.
Lets DRM start on my PCI card.
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/drm_bufs.c b/drivers/char/drm/drm_bufs.c
index 1845dd0..1db12dc 100644
--- a/drivers/char/drm/drm_bufs.c
+++ b/drivers/char/drm/drm_bufs.c
@@ -154,7 +154,7 @@
case _DRM_REGISTERS:
case _DRM_FRAME_BUFFER:
#if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__)
- if (map->offset + map->size < map->offset ||
+ if (map->offset + (map->size-1) < map->offset ||
map->offset < virt_to_phys(high_memory)) {
drm_free(map, sizeof(*map), DRM_MEM_MAPS);
return -EINVAL;