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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 25A56C32789 for ; Thu, 8 Nov 2018 08:56:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E429E20825 for ; Thu, 8 Nov 2018 08:56:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E429E20825 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726861AbeKHSbP (ORCPT ); Thu, 8 Nov 2018 13:31:15 -0500 Received: from mga02.intel.com ([134.134.136.20]:60690 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726145AbeKHSbP (ORCPT ); Thu, 8 Nov 2018 13:31:15 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Nov 2018 00:56:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,478,1534834800"; d="scan'208";a="272358766" Received: from kohsamui.iil.intel.com (HELO [10.236.193.12]) ([10.236.193.12]) by orsmga005.jf.intel.com with ESMTP; 08 Nov 2018 00:56:44 -0800 Subject: Re: [PATCH] lib/genaloc: Fix allocation of aligned buffer from non-aligned chunk To: Andrew Morton Cc: sbates@raithlin.com, logang@deltatee.com, danielmentz@google.com, mathieu.desnoyers@efficios.com, linux-kernel@vger.kernel.org, labbott@redhat.com References: <1541506853-10685-1-git-send-email-alexey.skidanov@intel.com> <20181106141131.76e94f6b1ff2859d96792aca@linux-foundation.org> <20181107141428.bd1f8b1a989449633394d8c1@linux-foundation.org> From: Alexey Skidanov Message-ID: <7c902049-4fc4-7c13-2ee3-c0a198767359@intel.com> Date: Thu, 8 Nov 2018 10:58:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181107141428.bd1f8b1a989449633394d8c1@linux-foundation.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/8/18 00:14, Andrew Morton wrote: > On Wed, 7 Nov 2018 08:21:07 +0200 Alexey Skidanov wrote: > >>> Why does this need "fixing"? Are there current callers which can >>> misalign chunk_start_addr? Or is there a requirement that future >>> callers can misalign chunk_start_addr? >>> >> I work on adding aligned allocation support for ION heaps >> (https://www.spinics.net/lists/linux-driver-devel/msg118754.html). Two >> of these heaps use genpool internally. >> >> If you want to have an ability to allocate buffers aligned on different >> boundaries (for example, 4K, 1MB, ...), this fix actually removes the >> requirement for chunk_start_addr to be aligned on the max possible >> alignment. > > OK. This sort of information should be in the changelog, please. In > much detail. > Sure, I'll add this information and resend the patch. Thanks, Alexey