From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4A55C04AAD for ; Tue, 7 May 2019 05:49:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7704F204FD for ; Tue, 7 May 2019 05:49:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557208140; bh=4Ruw6mUD4zBOCDiBbLvKaU1Nm+tiQj2boN6q3TPTB18=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=vppg2V1a6jWr+UnOjVt4Wqbm91II+8X1dqxT8x2QlX1XOLOwxOJYOkWPchJMSss0e Esw7hWAK+xLKpb3fj84fE7loNvmTPg+zXmh85oZeanTt5YDRR1fvfQGMudVDacwhZm 12LP8+hxB1fhC0vUPIr2gMwPXLuhzwEciG1SSSO4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729146AbfEGFkk (ORCPT ); Tue, 7 May 2019 01:40:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:60104 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729142AbfEGFkj (ORCPT ); Tue, 7 May 2019 01:40:39 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id ECDB5205ED; Tue, 7 May 2019 05:40:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557207639; bh=4Ruw6mUD4zBOCDiBbLvKaU1Nm+tiQj2boN6q3TPTB18=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LjiMBnFqwrkyL5H3KcTcobAxMWzYoiTWdC0MeV86TAsOH3OxzcGmiW7nOetBtdKF0 7yNG25HAH6n8BjmT4OR/QapehK4qyRRIOCuvjVckGfa/LOHQJiZwpncVtBtMTPY6jB Mb/w8ek7oX0hNNFLv5NoW7MSMr8nTdbHMO++sPOs= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alexey Brodkin , Alexey Brodkin , Greg Kroah-Hartman , Geert Uytterhoeven , David Laight , Peter Zijlstra , Thomas Gleixner , Vineet Gupta , Will Deacon , Greg KH , Sasha Levin Subject: [PATCH AUTOSEL 4.14 72/95] devres: Align data[] to ARCH_KMALLOC_MINALIGN Date: Tue, 7 May 2019 01:38:01 -0400 Message-Id: <20190507053826.31622-72-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190507053826.31622-1-sashal@kernel.org> References: <20190507053826.31622-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexey Brodkin [ Upstream commit a66d972465d15b1d89281258805eb8b47d66bd36 ] Initially we bumped into problem with 32-bit aligned atomic64_t on ARC, see [1]. And then during quite lengthly discussion Peter Z. mentioned ARCH_KMALLOC_MINALIGN which IMHO makes perfect sense. If allocation is done by plain kmalloc() obtained buffer will be ARCH_KMALLOC_MINALIGN aligned and then why buffer obtained via devm_kmalloc() should have any other alignment? This way we at least get the same behavior for both types of allocation. [1] http://lists.infradead.org/pipermail/linux-snps-arc/2018-July/004009.html [2] http://lists.infradead.org/pipermail/linux-snps-arc/2018-July/004036.html Signed-off-by: Alexey Brodkin Cc: Greg Kroah-Hartman Cc: Geert Uytterhoeven Cc: David Laight Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Vineet Gupta Cc: Will Deacon Cc: Greg KH Cc: # 4.8+ Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/base/devres.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 71d577025285..e43a04a495a3 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -25,8 +25,14 @@ struct devres_node { struct devres { struct devres_node node; - /* -- 3 pointers */ - unsigned long long data[]; /* guarantee ull alignment */ + /* + * Some archs want to perform DMA into kmalloc caches + * and need a guaranteed alignment larger than + * the alignment of a 64-bit integer. + * Thus we use ARCH_KMALLOC_MINALIGN here and get exactly the same + * buffer alignment as if it was allocated by plain kmalloc(). + */ + u8 __aligned(ARCH_KMALLOC_MINALIGN) data[]; }; struct devres_group { -- 2.20.1