From ce53e02d2f0fc29599c6d03cd7c382a7c44a384e Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sat, 29 Oct 2005 18:18:42 +0900 Subject: [PATCH] [PATCH] blk: fix merge bug in as-iosched as-iosched deals with aliased requests differently from other ioscheds. It links together aliased requests using rq->queuelist instead of spilling alises to dispatch queue like other ioscheds do. Requests linked in this way cannot be merged. Unfortunately, generic q->last_merge handling patch didn't take this into account and q->last_merge could be set to an aliased request resulting in Badness, corrupt list and eventually panic. This explicitly marks aliased requests to be unmergeable. Signed-off-by: Tejun Heo Signed-off-by: Linus Torvalds --- drivers/block/as-iosched.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/block/as-iosched.c b/drivers/block/as-iosched.c index 4081c36c8c19e..5641722348194 100644 --- a/drivers/block/as-iosched.c +++ b/drivers/block/as-iosched.c @@ -1344,6 +1344,7 @@ as_add_aliased_request(struct as_data *ad, struct as_rq *arq, struct as_rq *alia * Don't want to have to handle merges. */ as_del_arq_hash(arq); + arq->request->flags |= REQ_NOMERGE; } /* -- 2.39.5