lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

blk-mq: call blk_mq_start_request from ->queue_rq

Browse Source 
When we call blk_mq_start_request from the core blk-mq code before calling into
->queue_rq there is a racy window where the timeout handler can hit before we've
fully set up the driver specific part of the command.

Move the call to blk_mq_start_request into the driver so the driver can start
the request only once it is fully set up.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Christoph Hellwig
2014-09-13 16:40:09 -07:00
committed by Jens Axboe
parent bf57229745
commit e2490073cd
6 changed files with 14 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/scsi/scsi_lib.c
View File

@@ -1890,6 +1890,7 @@ static int scsi_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *req,
scsi_init_cmd_errh(cmd);
cmd->scsi_done = scsi_mq_done;
blk_mq_start_request(req);
reason = scsi_dispatch_cmd(cmd);
if (reason) {
scsi_set_blocked(cmd, reason);