When bio has only one physical segment, we should set bio's bi_seg_front_size as the real(final) size of the single segment. Fixes: 02e707424c2ea(blk-merge: fix blk_bio_segment_split) Reported-by: Markus Trippelsdorf <markus@xxxxxxxxxxxxxxx> Tested-by: Markus Trippelsdorf <markus@xxxxxxxxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxxxxx> --- block/blk-merge.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/blk-merge.c b/block/blk-merge.c index 41a55ba..e01405a 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -103,6 +103,9 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, bvprv = bv; bvprvp = &bvprv; sectors += bv.bv_len >> 9; + + if (nsegs == 1 && seg_size > front_seg_size) + front_seg_size = seg_size; continue; } new_segment: -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html