Am 31.08.2018 um 17:15 schrieb Michel Dänzer: > On 2018-08-31 3:10 p.m., Christian König wrote: >> Staring at the function for six hours, just to essentially move one line >> of code. > That sucks, but the commit log should describe what the problem was and > how this patch solves it. > > >> Signed-off-by: Christian König <christian.koenig at amd.com> >> --- >> drivers/gpu/drm/ttm/ttm_bo.c | 13 ++++++++----- >> 1 file changed, 8 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c >> index 35d53d81f486..138c98902033 100644 >> --- a/drivers/gpu/drm/ttm/ttm_bo.c >> +++ b/drivers/gpu/drm/ttm/ttm_bo.c >> @@ -250,15 +250,18 @@ EXPORT_SYMBOL(ttm_bo_move_to_lru_tail); >> static void ttm_bo_bulk_move_helper(struct ttm_lru_bulk_move_pos *pos, >> struct list_head *lru, bool is_swap) >> { >> + struct list_head *list; >> LIST_HEAD(entries); >> LIST_HEAD(before); >> - struct list_head *list1, *list2; >> >> - list1 = is_swap ? &pos->last->swap : &pos->last->lru; >> - list2 = is_swap ? pos->first->swap.prev : pos->first->lru.prev; >> + reservation_object_assert_held(pos->last->resv); >> + list = is_swap ? &pos->last->swap : &pos->last->lru; >> + list_cut_position(&entries, lru, list); >> + >> + reservation_object_assert_held(pos->first->resv); >> + list = is_swap ? pos->first->swap.prev : pos->first->lru.prev; >> + list_cut_position(&before, &entries, list); > So the problem was that the first list_cut_position call could result in > list2 pointing to la-la-land? Good catch! Yes, exactly. Thought that would be obvious, but going to add that to the commit log. Can I get a tested-by? You where much better at reproducing that than I'm. Christian.