From mboxrd@z Thu Jan  1 00:00:00 1970
From: hare@suse.de (Hannes Reinecke)
Date: Mon, 16 Jul 2018 12:58:35 +0200
Subject: [PATCH 3/5] nvme-multipath: fixup crash during disconnect
In-Reply-To: <20180716105837.101125-1-hare@suse.de>
References: <20180716105837.101125-1-hare@suse.de>
Message-ID: <20180716105837.101125-4-hare@suse.de>

The kernel will crash during disconnect, if the first path is
'optimized' and the second 'non-optimized'. Then upon removing the
first path any I/O coming in _before_ removing the second path will
find the first path to be unusable, and assign 'fallback' to the
second. But after exiting the loop it will assign the _first_ path
to 'current_path', leading to a crash later on.

Signed-off-by: Hannes Reinecke <hare at suse.com>
---
 drivers/nvme/host/multipath.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 8980b0137fa5..5205f41c0f6c 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -129,7 +129,7 @@ static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head)
 	}
 
 	if (fallback)
-		rcu_assign_pointer(head->current_path, ns);
+		rcu_assign_pointer(head->current_path, fallback);
 	return fallback;
 }
 
-- 
2.12.3