Although __bio_clone_fast() copies bi_io_vec, it does not copy bi_vcnt, the number of elements in bi_io_vec[] that contains data. Copy bi_vcnt such that code that needs this member behaves identically for original and for cloned requests. Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Cc: Mike Snitzer <snitzer@xxxxxxxxxx> Cc: Ming Lei <ming.lei@xxxxxxxxxx> Cc: Hannes Reinecke <hare@xxxxxxxx> Cc: Johannes Thumshirn <jthumshirn@xxxxxxx> --- block/bio.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/bio.c b/block/bio.c index f7e3d88bd0b6..55f8e0dedd69 100644 --- a/block/bio.c +++ b/block/bio.c @@ -605,6 +605,7 @@ void __bio_clone_fast(struct bio *bio, struct bio *bio_src) bio->bi_opf = bio_src->bi_opf; bio->bi_write_hint = bio_src->bi_write_hint; bio->bi_iter = bio_src->bi_iter; + bio->bi_vcnt = bio_src->bi_vcnt; bio->bi_io_vec = bio_src->bi_io_vec; bio_clone_blkcg_association(bio, bio_src); -- 2.17.1