From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753874AbdLMCKt (ORCPT ); Tue, 12 Dec 2017 21:10:49 -0500 Received: from omzsmtpe02.verizonbusiness.com ([199.249.25.209]:47774 "EHLO omzsmtpe02.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753259AbdLMCB6 (ORCPT ); Tue, 12 Dec 2017 21:01:58 -0500 From: alexander.levin@verizon.com Cc: Alexander Duyck , Jeff Kirsher , "David S . Miller" , alexander.levin@verizon.com X-Host: surveyor.tdc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH AUTOSEL for 3.18 18/40] i40e: Do not enable NAPI on q_vectors that have no rings Thread-Topic: [PATCH AUTOSEL for 3.18 18/40] i40e: Do not enable NAPI on q_vectors that have no rings Thread-Index: AQHTc7X6nxBvcnnfHkWgPDKi5IsnwQ== Date: Wed, 13 Dec 2017 01:59:15 +0000 Message-ID: <20171213015905.7059-18-alexander.levin@verizon.com> References: <20171213015905.7059-1-alexander.levin@verizon.com> In-Reply-To: <20171213015905.7059-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id vBD2ArP2016608 From: Alexander Duyck [ Upstream commit 13a8cd191a2b470cfd435b3b57dbd21aa65ff78c ] When testing the epoll w/ busy poll code I found that I could get into a state where the i40e driver had q_vectors w/ active NAPI that had no rings. This was resulting in a divide by zero error. To correct it I am updating the driver code so that we only support NAPI on q_vectors that have 1 or more rings allocated to them. Signed-off-by: Alexander Duyck Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/i40e/i40e_main.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c index 81cd60dd8a2f..f7ed3dbd9800 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_main.c +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c @@ -3814,8 +3814,12 @@ static void i40e_napi_enable_all(struct i40e_vsi *vsi) if (!vsi->netdev) return; - for (q_idx = 0; q_idx < vsi->num_q_vectors; q_idx++) - napi_enable(&vsi->q_vectors[q_idx]->napi); + for (q_idx = 0; q_idx < vsi->num_q_vectors; q_idx++) { + struct i40e_q_vector *q_vector = vsi->q_vectors[q_idx]; + + if (q_vector->rx.ring || q_vector->tx.ring) + napi_enable(&q_vector->napi); + } } /** @@ -3829,8 +3833,12 @@ static void i40e_napi_disable_all(struct i40e_vsi *vsi) if (!vsi->netdev) return; - for (q_idx = 0; q_idx < vsi->num_q_vectors; q_idx++) - napi_disable(&vsi->q_vectors[q_idx]->napi); + for (q_idx = 0; q_idx < vsi->num_q_vectors; q_idx++) { + struct i40e_q_vector *q_vector = vsi->q_vectors[q_idx]; + + if (q_vector->rx.ring || q_vector->tx.ring) + napi_disable(&q_vector->napi); + } } /** -- 2.11.0