[PATCH 4.3 014/200] block: ensure to split after potentially bouncing a bio
From: Greg Kroah-Hartman
Date: Sun Feb 14 2016 - 19:20:16 EST
4.3-stable review patch. If anyone has any objections, please let me know.
------------------
From: Junichi Nomura <j-nomura@xxxxxxxxxxxxx>
commit 23688bf4f830a89866fd0ed3501e342a7360fe4f upstream.
blk_queue_bio() does split then bounce, which makes the segment
counting based on pages before bouncing and could go wrong. Move
the split to after bouncing, like we do for blk-mq, and the we
fix the issue of having the bio count for segments be wrong.
Fixes: 54efd50bfd87 ("block: make generic_make_request handle arbitrarily sized bios")
Tested-by: Artem S. Tashkinov <t.artem@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
block/blk-core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1616,8 +1616,6 @@ static void blk_queue_bio(struct request
struct request *req;
unsigned int request_count = 0;
- blk_queue_split(q, &bio, q->bio_split);
-
/*
* low level driver can indicate that it wants pages above a
* certain limit bounced to low memory (ie for highmem, or even
@@ -1625,6 +1623,8 @@ static void blk_queue_bio(struct request
*/
blk_queue_bounce(q, &bio);
+ blk_queue_split(q, &bio, q->bio_split);
+
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
bio->bi_error = -EIO;
bio_endio(bio);