On Thu, Jun 02, 2022 at 04:21:29PM +0800, Yu Kuai wrote: > In filemap_read(), 'ra->prev_pos' is set to 'iocb->ki_pos + copied', > while it should be 'iocb->ki_ops'. Can you walk me through your reasoning which leads you to believe that it should be ki_pos instead of ki_pos + copied? As I understand it, prev_pos is the end of the previous read, not the beginning of the previous read. For consequence, > folio_mark_accessed() will not be called for 'fbatch.folios[0]' since > 'iocb->ki_pos' is always equal to 'ra->prev_pos'. I don't follow this, but maybe I'm just being slow.