From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:57160 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932384AbbIZVHN (ORCPT ); Sat, 26 Sep 2015 17:07:13 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jack Morgenstein , Or Gerlitz , Doug Ledford Subject: [PATCH 4.2 127/134] IB/mlx4: Fix potential deadlock when sending mad to wire Date: Sat, 26 Sep 2015 13:56:19 -0700 Message-Id: <20150926205319.505755457@linuxfoundation.org> In-Reply-To: <20150926205311.819185658@linuxfoundation.org> References: <20150926205311.819185658@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: stable-owner@vger.kernel.org List-ID: 4.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jack Morgenstein commit 90c1d8b6350cca9d8a234f03c77a317a7613bcee upstream. send_mad_to_wire takes the same spinlock that is taken in the interrupt context. Therefore, it needs irqsave/restore. Fixes: b9c5d6a64358 ('IB/mlx4: Add multicast group (MCG) paravirtualization for SR-IOV') Signed-off-by: Jack Morgenstein Signed-off-by: Or Gerlitz Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/mlx4/mcg.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/infiniband/hw/mlx4/mcg.c +++ b/drivers/infiniband/hw/mlx4/mcg.c @@ -206,15 +206,16 @@ static int send_mad_to_wire(struct mlx4_ { struct mlx4_ib_dev *dev = ctx->dev; struct ib_ah_attr ah_attr; + unsigned long flags; - spin_lock(&dev->sm_lock); + spin_lock_irqsave(&dev->sm_lock, flags); if (!dev->sm_ah[ctx->port - 1]) { /* port is not yet Active, sm_ah not ready */ - spin_unlock(&dev->sm_lock); + spin_unlock_irqrestore(&dev->sm_lock, flags); return -EAGAIN; } mlx4_ib_query_ah(dev->sm_ah[ctx->port - 1], &ah_attr); - spin_unlock(&dev->sm_lock); + spin_unlock_irqrestore(&dev->sm_lock, flags); return mlx4_ib_send_to_wire(dev, mlx4_master_func_num(dev->dev), ctx->port, IB_QPT_GSI, 0, 1, IB_QP1_QKEY, &ah_attr, NULL, mad);