| Message ID | 1448332531-10704-4-git-send-email-ming.lei@canonical.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Jens Axboe |
| Headers | show |
diff --git a/block/blk-merge.c b/block/blk-merge.c index 50793cd..41a55ba 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -428,6 +428,12 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, if (sg) sg_mark_end(sg); + /* + * Something must have been wrong if the figured number of + * segment is bigger than number of req's physical segments + */ + WARN_ON(nsegs > rq->nr_phys_segments); + return nsegs; } EXPORT_SYMBOL(blk_rq_map_sg);
We had seen lots of reports of this kind issue, so add one warnning in blk-merge, then it can be triggered easily and avoid to depend on warning/bug from drivers. Signed-off-by: Ming Lei <ming.lei@canonical.com> --- block/blk-merge.c | 6 ++++++ 1 file changed, 6 insertions(+)