drm/ttm: Don't clear page metadata of imported sg pages

These page pointers shouldn't be visible to TTM in the first place, but
until we fix that up, don't clear the page metadata because that
will upset the exporter.

Reported-and-tested-by: Cristoph Haag <haagch.christoph@googleemail.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>

diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 9af99084b344413dcb07c2a368916bff647fc119..75f319090043a69021467e0d8fc9840fa796067d 100644 (file)
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -380,6 +380,9 @@ static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
        pgoff_t i;
        struct page **page = ttm->pages;
 
+       if (ttm->page_flags & TTM_PAGE_FLAG_SG)
+               return;
+
        for (i = 0; i < ttm->num_pages; ++i) {
                (*page)->mapping = NULL;
                (*page++)->index = 0;