From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: Re: KVM VM shutdown triggers BUG from network bridge code in 3.9.9 Date: Fri, 5 Jul 2013 08:31:43 +0000 (UTC) Message-ID: References: <51D64BEC.7090208@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: linux-kernel@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 05 Jul 2013 at 04:30 GMT, Robert Hancock wrote: > I've run into a problem after updating to Fedora 19 where if I shut down > a Windows 7 KVM virtual machine, the machine hits a kernel panic. There > are a few reports of this on 3.9.8 and 3.9.9 kernels here: > > https://bugzilla.redhat.com/show_bug.cgi?id=981437 > > The panic is "kernel BUG at kernel/timer.c:729!" and the stack traces > all seem basically the same, something like this one (captured with kdump): > > #7 [ffff880214d25c10] mod_timer+501 at ffffffff8106d905 > #8 [ffff880214d25c50] br_multicast_del_pg.isra.20+261 at > ffffffffa0731d25 [bridge] Yeah, I got some similar bug report on Fedora... Could you try the following patch? Thanks! ---------- diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 81befac..69af490 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -270,7 +270,7 @@ static void br_multicast_del_pg(struct net_bridge *br, del_timer(&p->timer); call_rcu_bh(&p->rcu, br_multicast_free_pg); - if (!mp->ports && !mp->mglist && + if (!mp->ports && !mp->mglist && mp->timer_armed && netif_running(br->dev)) mod_timer(&mp->timer, jiffies);