From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753911AbcKJGTd (ORCPT ); Thu, 10 Nov 2016 01:19:33 -0500 Received: from mga11.intel.com ([192.55.52.93]:39594 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753522AbcKJGTc (ORCPT ); Thu, 10 Nov 2016 01:19:32 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,617,1473145200"; d="scan'208";a="1083228765" Subject: Re: [Intel-wired-lan] [PATCH v2] e1000e: free IRQ regardless of __E1000_DOWN To: Tyler Baicar , jeffrey.t.kirsher@intel.com, intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, okaya@codeaurora.org, timur@codeaurora.org References: <1478727681-16505-1-git-send-email-tbaicar@codeaurora.org> From: "Neftin, Sasha" Message-ID: <42e53bc2-0361-e7b7-1093-4e095aa56955@intel.com> Date: Thu, 10 Nov 2016 08:19:28 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1478727681-16505-1-git-send-email-tbaicar@codeaurora.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/9/2016 11:41 PM, Tyler Baicar wrote: > Move IRQ free code so that it will happen regardless of the > __E1000_DOWN bit. Currently the e1000e driver only releases its IRQ > if the __E1000_DOWN bit is cleared. This is not sufficient because > it is possible for __E1000_DOWN to be set without releasing the IRQ. > In such a situation, we will hit a kernel bug later in e1000_remove > because the IRQ still has action since it was never freed. A > secondary bus reset can cause this case to happen. > > Signed-off-by: Tyler Baicar > --- > drivers/net/ethernet/intel/e1000e/netdev.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c > index 7017281..36cfcb0 100644 > --- a/drivers/net/ethernet/intel/e1000e/netdev.c > +++ b/drivers/net/ethernet/intel/e1000e/netdev.c > @@ -4679,12 +4679,13 @@ int e1000e_close(struct net_device *netdev) > > if (!test_bit(__E1000_DOWN, &adapter->state)) { > e1000e_down(adapter, true); > - e1000_free_irq(adapter); > > /* Link status message must follow this format */ > pr_info("%s NIC Link is Down\n", adapter->netdev->name); > } > > + e1000_free_irq(adapter); > + > napi_disable(&adapter->napi); > > e1000e_free_tx_resources(adapter->tx_ring); > I would like not recommend insert this change. This change related driver state machine, we afraid from lot of synchronization problem and issues. We need keep e1000_free_irq in loop and check for 'test_bit' ready. Another point, does before execute secondary bus reset your SW back up pcie configuration space as properly? Sasha