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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 E74ECC04E53 for ; Wed, 15 May 2019 11:18:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB68E20843 for ; Wed, 15 May 2019 11:18:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557919121; bh=p3ZG5RJaKfArlN53APF3EKv1lFnczoNnYj2IOkU0MpU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Jdk+0DZRXmN7WNWvbvsqCJE+dE/5srX1FJSMS9UNcNzvRdAFdO+HlvUq0+sWmA967 +QZGRGld8okGntT6pXRYRDc2MVo+3dXh8VR9c5AmioVyThsKvgliKbcZHO1YcRmcwQ WvENjdv/cVZPzWGUL3QZbRtyMpuUYL0o3x2kyW5Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730371AbfEOLSk (ORCPT ); Wed, 15 May 2019 07:18:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:56142 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730833AbfEOLSj (ORCPT ); Wed, 15 May 2019 07:18:39 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B76E4206BF; Wed, 15 May 2019 11:18:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557919119; bh=p3ZG5RJaKfArlN53APF3EKv1lFnczoNnYj2IOkU0MpU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tmDTfT1YNkGp72xaeKC+0iFI4cyu4ka7uquwGwhRlt3GN4TgzlAMxxfqYFI0QIJei b0CMcbxVE9wlSdzMsqq5YOlKO+n3bYQJnuFKdr5pJ2gnWQtRjou2iC4NrYvzzc83F7 8XEQIp1xslHbXfICFXIJh/EvIFEzTD62Q8dT1hlE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexey Brodkin , Geert Uytterhoeven , David Laight , Peter Zijlstra , Thomas Gleixner , Vineet Gupta , Will Deacon , Greg KH , Sasha Levin Subject: [PATCH 4.14 074/115] devres: Align data[] to ARCH_KMALLOC_MINALIGN Date: Wed, 15 May 2019 12:55:54 +0200 Message-Id: <20190515090704.786241438@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090659.123121100@linuxfoundation.org> References: <20190515090659.123121100@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ 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 71d577025285b..e43a04a495a31 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