Yeah, that's a good point.
If build_bug_on() doesn't works for some reason then we at least need to
lower this to a WARN_ON.
A BUG_ON() is only justified if we prevent strong data corruption with
it or note a NULL pointer earlier on or similar.
Regards,
Christian.
Am 10.09.21 um 06:36 schrieb Pan, Xinhui:
[AMD Official Use Only]
looks good to me.
But maybe build_bug_on works too and more reasonable to detect such
wrong usage.
------------------------------------------------------------------------
*From:* Chen, Guchun <[email protected]>
*Sent:* Friday, September 10, 2021 12:30:14 PM
*To:* [email protected] <[email protected]>;
[email protected] <[email protected]>;
Koenig, Christian <[email protected]>; Pan, Xinhui
<[email protected]>; Deucher, Alexander <[email protected]>
*Cc:* Chen, Guchun <[email protected]>; Shi, Leslie
<[email protected]>
*Subject:* [PATCH] drm/ttm: add a BUG_ON in ttm_set_driver_manager
when array bounds
Vendor will define their own memory types on top of TTM_PL_PRIV,
but call ttm_set_driver_manager directly without checking mem_type
value when setting up memory manager. So add such check to aware
the case when array bounds.
Signed-off-by: Leslie Shi <[email protected]>
Signed-off-by: Guchun Chen <[email protected]>
---
include/drm/ttm/ttm_device.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/include/drm/ttm/ttm_device.h b/include/drm/ttm/ttm_device.h
index 7a0f561c57ee..24ad76ca8022 100644
--- a/include/drm/ttm/ttm_device.h
+++ b/include/drm/ttm/ttm_device.h
@@ -308,6 +308,7 @@ ttm_manager_type(struct ttm_device *bdev, int
mem_type)
static inline void ttm_set_driver_manager(struct ttm_device *bdev,
int type,
struct ttm_resource_manager
*manager)
{
+ BUG_ON(type >= TTM_NUM_MEM_TYPES);
bdev->man_drv[type] = manager;
}
--
2.17.1
