From: Ville Syrjälä Date: Wed, 21 Apr 2021 15:33:58 +0000 (+0300) Subject: drm/i915: Avoid div-by-zero on gen2 X-Git-Tag: v5.13-rc2~19^2~1^2~5 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4819d16d91145966ce03818a95169df1fd56b299;p=users%2Fhch%2Fmisc.git drm/i915: Avoid div-by-zero on gen2 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@vger.kernel.org Reviewed-by: Chris Wilson Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20210421153401.13847-2-ville.syrjala@linux.intel.com (cherry picked from commit ed52c62d386f764194e0184fdb905d5f24194cae) Signed-off-by: Jani Nikula --- diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index 23f6b00e08e2..f6fe5cb01438 100644 --- 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_i915_gem_object *obj, 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);