blk: Fix bio_io_vec index when checking bvec gaps

Corrects a coding error from earlier patch.

Reported by: Sagi Grimberg <sagig@dev.mellanox.co.il>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Fixes: 03100aada96f ("block: Replace SG_GAPS with new queue limits mask")
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-merge.c b/block/blk-merge.c
index 0e0d9fd01c409a3f9351da723a0d1347e3977a9c..b2625271a572ba1627bb949d806a4d891b1dd953 100644 (file)
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -488,7 +488,7 @@ static int req_gap_to_prev(struct request *req, struct bio *next)
        struct bio *prev = req->biotail;
 
        return bvec_gap_to_prev(req->q, &prev->bi_io_vec[prev->bi_vcnt - 1],
-                       next->bi_io_vec[1].bv_offset);
+                       next->bi_io_vec[0].bv_offset);
 }
 
 static int ll_merge_requests_fn(struct request_queue *q, struct request *req,