[PATCH 4.14 217/246] block: reset bi_iter.bi_done after splitting bio

From: Greg Kroah-Hartman
Date: Wed Aug 01 2018 - 13:50:04 EST

4.14-stable review patch. If anyone has any objections, please let me know.


From: Greg Edwards <gedwards@xxxxxxx>

commit 5151842b9d8732d4cbfa8400b40bff894f501b2f upstream.

After the bio has been updated to represent the remaining sectors, reset
bi_done so bio_rewind_iter() does not rewind further than it should.

This resolves a bio_integrity_process() failure on reads where the
original request was split.

Fixes: 63573e359d05 ("bio-integrity: Restore original iterator on verify stage")
Signed-off-by: Greg Edwards <gedwards@xxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

block/bio.c | 1 +
1 file changed, 1 insertion(+)

--- a/block/bio.c
+++ b/block/bio.c
@@ -1889,6 +1889,7 @@ struct bio *bio_split(struct bio *bio, i

bio_advance(bio, split->bi_iter.bi_size);
+ bio->bi_iter.bi_done = 0;

if (bio_flagged(bio, BIO_TRACE_COMPLETION))
bio_set_flag(split, BIO_TRACE_COMPLETION);