From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Herbert Subject: [PATCH net-next] mlx5: Add MLX5_SET64_VCHK to fix BUILD_BUG_ON Date: Mon, 10 Oct 2016 21:22:22 -0700 Message-ID: <20161011042222.2366145-1-tom@herbertland.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Cc: To: , , Return-path: Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:50250 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751123AbcJKEWg (ORCPT ); Tue, 11 Oct 2016 00:22:36 -0400 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.17/8.16.0.17) with SMTP id u9B4M5g3017740 for ; Mon, 10 Oct 2016 21:22:36 -0700 Received: from mail.thefacebook.com ([199.201.64.23]) by m0001303.ppops.net with ESMTP id 25xvfbxh4t-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Mon, 10 Oct 2016 21:22:36 -0700 Received: from facebook.com (2401:db00:21:6030:face:0:92:0) by mx-out.facebook.com (10.212.232.59) with ESMTP id 54f283e48f6a11e692c80002c991e86a-321eea50 for ; Mon, 10 Oct 2016 21:22:33 -0700 Sender: netdev-owner@vger.kernel.org List-ID: I am hitting this in mlx5: drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c: In function ‘reclaim_pages_cmd.clone.0’: drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:346: error: call to ‘__compiletime_assert_346’ declared with attribute error: BUILD_BUG_ON failed: __mlx5_bit_off(manage_pages_out, pas[i]) % 64 drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c: In function ‘give_pages’: drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c:291: error: call to ‘__compiletime_assert_291’ declared with attribute error: BUILD_BUG_ON failed: __mlx5_bit_off(manage_pages_in, pas[i]) % 64 Problem is that this is doing a BUILD_BUG_ON on a non-constant expression because of trying to take offset of pas[i] in the structure. Fix is to create MLX5_SET64_VCHK that takes an additional argument that is a constant. There are two callers of MLX5_SET64 that are trying to get a variable offset, change those to call MLX5_SET64_VCHK passing pas[0] as the argument to use in the offset check. Fixes: a533ed5e179cd ("net/mlx5: Pages management commands via mlx5 ifc") Signed-off-by: Tom Herbert --- drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c | 5 +++-- include/linux/mlx5/device.h | 13 +++++++++++-- 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c index d458515..5ef5ae2 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c @@ -287,7 +287,7 @@ retry: goto retry; } - MLX5_SET64(manage_pages_in, in, pas[i], addr); + MLX5_SET64_VCHK(manage_pages_in, in, pas[i], pas[0], addr); } MLX5_SET(manage_pages_in, in, opcode, MLX5_CMD_OP_MANAGE_PAGES); @@ -344,7 +344,8 @@ static int reclaim_pages_cmd(struct mlx5_core_dev *dev, if (fwp->func_id != func_id) continue; - MLX5_SET64(manage_pages_out, out, pas[i], fwp->addr); + MLX5_SET64_VCHK(manage_pages_out, out, pas[i], pas[0], + fwp->addr); i++; } diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h index 77c1417..943eb18 100644 --- a/include/linux/mlx5/device.h +++ b/include/linux/mlx5/device.h @@ -92,12 +92,21 @@ __mlx5_mask(typ, fld)) ___t; \ }) -#define MLX5_SET64(typ, p, fld, v) do { \ +#define __MLX5_SET64(typ, p, fld, v) do { \ BUILD_BUG_ON(__mlx5_bit_sz(typ, fld) != 64); \ - BUILD_BUG_ON(__mlx5_bit_off(typ, fld) % 64); \ *((__be64 *)(p) + __mlx5_64_off(typ, fld)) = cpu_to_be64(v); \ } while (0) +#define MLX5_SET64(typ, p, fld, v) do { \ + BUILD_BUG_ON(__mlx5_bit_off(typ, fld) % 64); \ + __MLX5_SET64(typ, p, fld, v); \ +} while (0) + +#define MLX5_SET64_VCHK(typ, p, fld, const_fld, v) do { \ + BUILD_BUG_ON(__mlx5_bit_off(typ, const_fld) % 64); \ + __MLX5_SET64(typ, p, fld, v); \ +} while (0) + #define MLX5_GET64(typ, p, fld) be64_to_cpu(*((__be64 *)(p) + __mlx5_64_off(typ, fld))) #define MLX5_GET64_PR(typ, p, fld) ({ \ -- 2.9.3