From b386a3a9a2a5443a038cdc7b4e88c6ac50539cf9 Mon Sep 17 00:00:00 2001
From: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Date: Fri, 8 Nov 2019 07:17:18 +0900
Subject: [PATCH] lib/scsi: Assert if ref count of task goes negative

We didn't have any check if ref count of SCSI task doesn't go negative.
This addition will verify the idea to LUN hotplug issue by subsequent
patches.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Signed-off-by: Ziye Yang <ziye.yang@intel.com>
Change-Id: I1d6ca9b9439bc7c4b701b65cc004cdf5cae16e91
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/473585
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
---
 lib/scsi/task.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/scsi/task.c b/lib/scsi/task.c
index d49deaa7f6..0058f642c3 100644
--- a/lib/scsi/task.c
+++ b/lib/scsi/task.c
@@ -47,6 +47,7 @@ spdk_scsi_task_put(struct spdk_scsi_task *task)
 		return;
 	}
 
+	assert(task->ref > 0);
 	task->ref--;
 
 	if (task->ref == 0) {