From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752925AbcLFM3h (ORCPT ); Tue, 6 Dec 2016 07:29:37 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36241 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752126AbcLFM3e (ORCPT ); Tue, 6 Dec 2016 07:29:34 -0500 Date: Tue, 6 Dec 2016 13:29:31 +0100 From: Jiri Pirko To: Feng Deng Cc: davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, cxdx2006@gmail.com Subject: Re: [PATCH] net:switchdev: fix to release the lock before function return to avoid deadlock Message-ID: <20161206122931.GJ1984@nanopsycho> References: <1481018964-47554-1-git-send-email-feng.deng@cortina-access.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1481018964-47554-1-git-send-email-feng.deng@cortina-access.com> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Tue, Dec 06, 2016 at 11:09:24AM CET, feng.deng@cortina-access.com wrote: >before switchdev_deferred_dequeue() normal return,show release the lock, >if not,maybe there will be deadlock sometimes > >Signed-off-by: Feng Deng >--- > net/switchdev/switchdev.c | 1 + > 1 file changed, 1 insertion(+) > >diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c >index 3b95fe9..c0a1ad4 100644 >--- a/net/switchdev/switchdev.c >+++ b/net/switchdev/switchdev.c >@@ -120,6 +120,7 @@ static struct switchdev_deferred_item *switchdev_deferred_dequeue(void) > dfitem = list_first_entry(&deferred, > struct switchdev_deferred_item, list); > list_del(&dfitem->list); >+ spin_unlock_bh(&deferred_lock); > unlock: > spin_unlock_bh(&deferred_lock); You are joking right?