This is a note to let you know that I've just added the patch titled block: don't optimize for non-cloned bio in bio_get_last_bvec() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: block-don-t-optimize-for-non-cloned-bio-in-bio_get_last_bvec.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 90d0f0f11588ec692c12f9009089b398be395184 Mon Sep 17 00:00:00 2001 From: Ming Lei <ming.lei@xxxxxxxxxxxxx> Date: Sat, 12 Mar 2016 22:56:19 +0800 Subject: block: don't optimize for non-cloned bio in bio_get_last_bvec() From: Ming Lei <ming.lei@xxxxxxxxxxxxx> commit 90d0f0f11588ec692c12f9009089b398be395184 upstream. 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) Reported-by: Kent Overstreet <kent.overstreet@xxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/bio.h | 5 ----- 1 file changed, 5 deletions(-) --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -320,11 +320,6 @@ static inline void bio_get_last_bvec(str 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; Patches currently in stable-queue which might be from ming.lei@xxxxxxxxxxxxx are queue-4.4/block-don-t-optimize-for-non-cloned-bio-in-bio_get_last_bvec.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html