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!
--
Earthling Michel Dänzer | http://www.amd.com
Libre software enthusiast | Mesa and X developer
