[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220801114129.332434263@linuxfoundation.org>
Date: Mon, 1 Aug 2022 13:47:14 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-kernel@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
stable@...r.kernel.org, Hannes Reinecke <hare@...e.com>,
Sumit Saxena <sumit.saxena@...adcom.com>,
Kashyap Desai <kashyap.desai@...adcom.com>,
Bart Van Assche <bvanassche@....org>,
Ewan Milne <emilne@...hat.com>, Long Li <longli@...rosoft.com>,
John Garry <john.garry@...wei.com>,
"chenxiang (M)" <chenxiang66@...ilicon.com>,
Ming Lei <ming.lei@...hat.com>,
"Martin K. Petersen" <martin.petersen@...cle.com>,
Yu Kuai <yukuai3@...wei.com>
Subject: [PATCH 5.4 34/34] scsi: core: Fix race between handling STS_RESOURCE and completion
From: Ming Lei <ming.lei@...hat.com>
commit 673235f915318ced5d7ec4b2bfd8cb909e6a4a55 upstream.
When queuing I/O request to LLD, STS_RESOURCE may be returned because:
- Host is in recovery or blocked
- Target queue throttling or target is blocked
- LLD rejection
In these scenarios BLK_STS_DEV_RESOURCE is returned to the block layer to
avoid an unnecessary re-run of the queue. However, all of the requests
queued to this SCSI device may complete immediately after reading
'sdev->device_busy' and BLK_STS_DEV_RESOURCE is returned to block layer. In
that case the current I/O won't get a chance to get queued since it is
invisible at that time for both scsi_run_queue_async() and blk-mq's
RESTART.
Fix the issue by not returning BLK_STS_DEV_RESOURCE in this situation.
Link: https://lore.kernel.org/r/20201202100419.525144-1-ming.lei@redhat.com
Fixes: 86ff7c2a80cd ("blk-mq: introduce BLK_STS_DEV_RESOURCE")
Cc: Hannes Reinecke <hare@...e.com>
Cc: Sumit Saxena <sumit.saxena@...adcom.com>
Cc: Kashyap Desai <kashyap.desai@...adcom.com>
Cc: Bart Van Assche <bvanassche@....org>
Cc: Ewan Milne <emilne@...hat.com>
Cc: Long Li <longli@...rosoft.com>
Reported-by: John Garry <john.garry@...wei.com>
Tested-by: "chenxiang (M)" <chenxiang66@...ilicon.com>
Signed-off-by: Ming Lei <ming.lei@...hat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@...cle.com>
Signed-off-by: Yu Kuai <yukuai3@...wei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
drivers/scsi/scsi_lib.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1719,8 +1719,7 @@ out_put_budget:
case BLK_STS_OK:
break;
case BLK_STS_RESOURCE:
- if (atomic_read(&sdev->device_busy) ||
- scsi_device_blocked(sdev))
+ if (scsi_device_blocked(sdev))
ret = BLK_STS_DEV_RESOURCE;
break;
default:
Powered by blists - more mailing lists