From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
commit 4819d16d91145966ce03818a95169df1fd56b299 upstream.
Gen2 tiles are 2KiB in size so i915_gem_object_get_tile_row_size()
can in fact return <4KiB, which leads to div-by-zero here.
Avoid that.
Not sure i915_gem_object_get_tile_row_size() is entirely
sane anyway since it doesn't account for the different tile
layouts on i8xx/i915...
I'm not able to hit this before commit 6846895fde05 ("drm/i915:
Replace PIN_NONFAULT with calls to PIN_NOEVICT") and it looks
like I also need to run recent version of Mesa. With those in
place xonotic trips on this quite easily on my 85x.
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20210421153401.13847-2-ville.syrjala@xxxxxxxxxxxxxxx
(cherry picked from commit ed52c62d386f764194e0184fdb905d5f24194cae)
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -189,7 +189,7 @@ compute_partial_view(const struct drm_i9
struct i915_ggtt_view view;
if (i915_gem_object_is_tiled(obj))
- chunk = roundup(chunk, tile_row_pages(obj));
+ chunk = roundup(chunk, tile_row_pages(obj) ?: 1);
view.type = I915_GGTT_VIEW_PARTIAL;
view.partial.offset = rounddown(page_offset, chunk);
