From: zhong jiang zhongjiang@huawei.com Subject: 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.... 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 ---

drivers/base/memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/base/memory.c~mm-memory_hotplug-do-not-unlock-when-fails-to-take-the-device_hotplug_lock +++ a/drivers/base/memory.c @@ -506,7 +506,7 @@ static ssize_t probe_store(struct device

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, _