Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754022AbcJZGvO (ORCPT ); Wed, 26 Oct 2016 02:51:14 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:36711 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752794AbcJZGvI (ORCPT ); Wed, 26 Oct 2016 02:51:08 -0400 Subject: Re: [PATCH] IB/mlx4: avoid a -Wmaybe-uninitialize warning To: Arnd Bergmann References: <20161025161632.411899-1-arnd@arndb.de> Cc: Yishai Hadas , "David S. Miller" , Jack Morgenstein , Or Gerlitz , Eran Ben Elisha , Moshe Shemesh , Christophe Jaillet , Moni Shoua , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org From: Yishai Hadas Message-ID: <3a7b4d28-1700-7545-c1b7-7d2d463a17d7@dev.mellanox.co.il> Date: Wed, 26 Oct 2016 09:51:04 +0300 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161025161632.411899-1-arnd@arndb.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1380 Lines: 40 On 10/25/2016 7:16 PM, Arnd Bergmann wrote: > There is an old warning about mlx4_SW2HW_EQ_wrapper on x86: > > ethernet/mellanox/mlx4/resource_tracker.c: In function ‘mlx4_SW2HW_EQ_wrapper’: > ethernet/mellanox/mlx4/resource_tracker.c:3071:10: error: ‘eq’ may be used uninitialized in this function [-Werror=maybe-uninitialized] > > The problem here is that gcc won't track the state of the variable > across a spin_unlock. Moving the assignment out of the lock is > safe here and avoids the warning. > > Signed-off-by: Arnd Bergmann Reviewed-by: Yishai Hadas > --- > drivers/net/ethernet/mellanox/mlx4/resource_tracker.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c > index 84d7857ccc27..c548beaaf910 100644 > --- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c > +++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c > @@ -1605,13 +1605,14 @@ static int eq_res_start_move_to(struct mlx4_dev *dev, int slave, int index, > r->com.from_state = r->com.state; > r->com.to_state = state; > r->com.state = RES_EQ_BUSY; > - if (eq) > - *eq = r; > } > } > > spin_unlock_irq(mlx4_tlock(dev)); > > + if (!err && eq) > + *eq = r; > + > return err; > } > >