Commit 1047bd82 authored by Thomas Hellström's avatar Thomas Hellström
Browse files

drm/xe: Fix incorrect migration of backed-up object to VRAM 

If an object is backed up to shmem it is incorrectly identified
as not having valid data by the move code. This means moving
to VRAM skips the -EMULTIHOP step and the bo is cleared. This
causes all sorts of weird behaviour on DGFX if an already evicted
object is targeted by the shrinker.

Fix this by using ttm_tt_is_swapped() to identify backed-up
objects.

Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/5996


Fixes: 00c8efc3 ("drm/xe: Add a shrinker for xe bos")
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: <stable@vger.kernel.org> # v6.15+
Signed-off-by: default avatarThomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: default avatarMatthew Auld <matthew.auld@intel.com>
Link: https://lore.kernel.org/r/20250828134837.5709-1-thomas.hellstrom@linux.intel.com
parent eeb8117f

drivers/gpu/drm/xe/xe_bo.c

+1 −2
Original line number Diff line number Diff line
@@ -823,8 +823,7 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict, 
		return ret;

	}



	tt_has_data = ttm && (ttm_tt_is_populated(ttm) ||

			      (ttm->page_flags & TTM_TT_FLAG_SWAPPED));

	tt_has_data = ttm && (ttm_tt_is_populated(ttm) || ttm_tt_is_swapped(ttm));



	move_lacks_source = !old_mem || (handle_system_ccs ? (!bo->ccs_cleared) :

					 (!mem_type_is_vram(old_mem_type) && !tt_has_data));