1 files changed, 8 insertions, 0 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 7497d86fff38..c3399bf29e9c 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -279,6 +279,14 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
 	return NULL;
 split:
 	*segs = nsegs;
+
+	/*
+	 * Bio splitting may cause subtle trouble such as hang when doing sync
+	 * iopoll in direct IO routine. Given performance gain of iopoll for
+	 * big IO can be trival, disable iopoll when split needed.
+	 */
+	bio->bi_opf &= ~REQ_HIPRI;
+
 	return bio_split(bio, sectors, GFP_NOIO, bs);
 }