From 37803841c92d7b327147e0b1be3436423189e1cf Mon Sep 17 00:00:00 2001
From: zhong jiang <zhongjiang@huawei.com>
Date: Thu, 18 Apr 2019 17:50:16 -0700
Subject: [PATCH] mm/memory_hotplug: do not unlock after failing to take the
 device_hotplug_lock

When adding memory by probing a memory block in the sysfs interface,
there is an obvious issue where we will unlock the device_hotplug_lock
when we failed to takes it.

That issue was introduced in 8df1d0e4a265 ("mm/memory_hotplug: make
add_memory() take the device_hotplug_lock").

We should drop out in time when failing to take the device_hotplug_lock.

Link: http://lkml.kernel.org/r/1554696437-9593-1-git-send-email-zhongjiang@huawei.com
Fixes: 8df1d0e4a265 ("mm/memory_hotplug: make add_memory() take the device_hotplug_lock")
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reported-by: Yang yingliang <yangyingliang@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 drivers/base/memory.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index cb8347500ce2..e49028a60429 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -506,7 +506,7 @@ static ssize_t probe_store(struct device *dev, struct device_attribute *attr,
 
 	ret = lock_device_hotplug_sysfs();
 	if (ret)
-		goto out;
+		return ret;
 
 	nid = memory_add_physaddr_to_nid(phys_addr);
 	ret = __add_memory(nid, phys_addr,