[PATCH 2/6] drm/nouveau: reject empty VRAM ranges

[Jiale Yao <yaojiale02@163.com>]

A VRAM range smaller than a page becomes a zero-page TTM range and
causes drm_mm_init() to hit its zero-range BUG check. Reject it before
creating the VRAM manager.

Fixes: 37205891d84f ("drm/ttm: make ttm_range_man_init/takedown take type + args")
Signed-off-by: Jiale Yao <yaojiale02@163.com>
---
 drivers/gpu/drm/nouveau/nouveau_ttm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c b/drivers/gpu/drm/nouveau/nouveau_ttm.c
index cfc0868e2dd3..99c74c3b5976 100644
--- a/drivers/gpu/drm/nouveau/nouveau_ttm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c
@@ -181,6 +181,9 @@ nouveau_ttm_init_host(struct nouveau_drm *drm, u8 kind)
 static int
 nouveau_ttm_init_vram(struct nouveau_drm *drm)
 {
+	if (drm->gem.vram_available < PAGE_SIZE)
+		return -EINVAL;
+
 	if (drm->client.device.info.family >= NV_DEVICE_INFO_V0_TESLA) {
 		struct ttm_resource_manager *man = kzalloc_obj(*man);
 
-- 
2.34.1