For !BIO_CLONED bio, we can use .bi_vcnt safely, but it doesn't mean we can just simply return .bi_io_vec[.bi_vcnt - 1] because the start postion may have been moved in the middle of the bvec, such as splitting in the middle of bvec.
Fixes: 7bcd79ac50d9(block: bio: introduce helpers to get the 1st and last bvec) Cc: [email protected] Reported-by: Kent Overstreet <[email protected]> Signed-off-by: Ming Lei <[email protected]> --- Jens, I am fine with either reverting previous patchset or applying this one to v4.5, and you decide it. Thanks Kent for reporting the issue! include/linux/bio.h | 5 ----- 1 file changed, 5 deletions(-) diff --git a/include/linux/bio.h b/include/linux/bio.h index 1e7248f..4abc129 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -267,11 +267,6 @@ static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) struct bvec_iter iter = bio->bi_iter; int idx; - if (!bio_flagged(bio, BIO_CLONED)) { - *bv = bio->bi_io_vec[bio->bi_vcnt - 1]; - return; - } - if (unlikely(!bio_multiple_segments(bio))) { *bv = bio_iovec(bio); return; -- 1.9.1
