drm: Fix error handling in drm_mm eviction kselftest

        drivers/gpu/drm/selftests/test-drm_mm.c:1277 evict_everything()
        warn: calling list_del() inside list_for_each

The list_del() inside the error handling in the eviction loop is
overkill. We have to undo the eviction scan to return the drm_mm back to
a recoverable state, so have to iterate over the full list, but we only
want to report the error once and once we have an error we can return
early.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 560b32842912 ("drm: kselftest for drm_mm and eviction")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170110144031.7609-1-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/selftests/test-drm_mm.c b/drivers/gpu/drm/selftests/test-drm_mm.c
index 6d2a5cd..6df53e6 100644 (file)
--- a/drivers/gpu/drm/selftests/test-drm_mm.c
+++ b/drivers/gpu/drm/selftests/test-drm_mm.c
@@ -1274,13 +1274,19 @@ static bool evict_everything(struct drm_mm *mm,
                if (drm_mm_scan_add_block(&scan, &e->node))
                        break;
        }
+
+       err = 0;
        list_for_each_entry(e, &evict_list, link) {
                if (!drm_mm_scan_remove_block(&scan, &e->node)) {
-                       pr_err("Node %lld not marked for eviction!\n",
-                              e->node.start);
-                       list_del(&e->link);
+                       if (!err) {
+                               pr_err("Node %lld not marked for eviction!\n",
+                                      e->node.start);
+                               err = -EINVAL;
+                       }
                }
        }
+       if (err)
+               return false;
 
        list_for_each_entry(e, &evict_list, link)
                drm_mm_remove_node(&e->node);