From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:40500 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750905AbdAXIAK (ORCPT ); Tue, 24 Jan 2017 03:00:10 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eli Cohen , Maor Gottlieb , Leon Romanovsky , Doug Ledford Subject: [PATCH 4.9 004/130] IB/mlx5: Avoid system crash when enabling many VFs Date: Tue, 24 Jan 2017 08:54:04 +0100 Message-Id: <20170124075535.095615590@linuxfoundation.org> In-Reply-To: <20170124075534.905042535@linuxfoundation.org> References: <20170124075534.905042535@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eli Cohen commit afd02cd3a9b6c04b41d946b5d7f6e17b3fc30c6b upstream. When enabling many VFs, the total amount of DMA mappings increase significantly. This causes DMA allocations to take a lot of time since they are serialized in the kernel. As a result the driver enters into fatal condition due to timeout and the system hangs. To recover from this we disable MR cache for VFs. PFs will still have a full cache and VFs cache can be manipulated as usual after driver load. Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters') Signed-off-by: Eli Cohen Signed-off-by: Maor Gottlieb Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/mlx5/mr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -628,7 +628,8 @@ int mlx5_mr_cache_init(struct mlx5_ib_de ent->order = i + 2; ent->dev = dev; - if (dev->mdev->profile->mask & MLX5_PROF_MASK_MR_CACHE) + if ((dev->mdev->profile->mask & MLX5_PROF_MASK_MR_CACHE) && + (mlx5_core_is_pf(dev->mdev))) limit = dev->mdev->profile->mr_cache[i].limit; else limit = 0;