Merge remote branch 'nouveau/for-airlied' of ../drm-nouveau-next into drm-core-next

[airlied - add fix for vmwgfx build]

* 'nouveau/for-airlied' of ../drm-nouveau-next: (93 commits)
  drm/ttm: restructure to allow driver to plug in alternate memory manager
  drm/ttm: introduce utility function to free an allocated memory node
  drm/nouveau: fix thinkos in mem timing table recordlen check
  drm/nouveau: parse voltage from perf 0x40 entires
  drm/nouveau: don't use the default pll limits in table v2.1 on nv50+ cards
  drm/nv50: Fix large 3D performance regression caused by the interchannel sync patches.
  drm/nouveau: Synchronize buffer object moves in hardware.
  drm/nouveau: Use semaphores to handle inter-channel sync in hardware.
  drm/nouveau: Provide a means to have arbitrary work run on fence completion.
  drm/nouveau: Minor refactoring/cleanup of the fence code.
  drm/nouveau: Add a module option to force card POST.
  drm/nv50: prevent (IB_PUT == IB_GET) for occurring unless idle
  drm/nv0x-nv4x: Leave the 0x40 bit untouched when changing CRE_LCD.
  drm/nv30-nv40: Fix postdivider mask when writing engine/memory PLLs.
  drm/nouveau: Fix perf table parsing on BMP v5.25.
  drm/nouveau: fix required mode bandwidth calculation for DP
  drm/nouveau: fix typo in c2aa91afea5f7e7ae4530fabd37414a79c03328c
  drm/nva3: split pm backend out from nv50
  drm/nouveau: run perflvl and M table scripts on mem clock change
  drm/nouveau: pass perflvl struct to clock_pre()
  ...
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
index b27a9f2..e730418 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fb.c
@@ -612,6 +612,7 @@
 {
 	struct ttm_buffer_object *bo = &vmw_bo->base;
 	struct ttm_placement ne_placement = vmw_vram_ne_placement;
+	struct drm_mm_node *mm_node;
 	int ret = 0;
 
 	ne_placement.lpfn = bo->num_pages;
@@ -625,8 +626,9 @@
 	if (unlikely(ret != 0))
 		goto err_unlock;
 
+	mm_node = bo->mem.mm_node;
 	if (bo->mem.mem_type == TTM_PL_VRAM &&
-	    bo->mem.mm_node->start < bo->num_pages)
+	    mm_node->start < bo->num_pages)
 		(void) ttm_bo_validate(bo, &vmw_sys_placement, false,
 				       false, false);