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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 C9EB4C433E0 for ; Mon, 8 Mar 2021 03:20:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84CE964F29 for ; Mon, 8 Mar 2021 03:20:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233884AbhCHDUZ (ORCPT ); Sun, 7 Mar 2021 22:20:25 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:13865 "EHLO szxga07-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231294AbhCHDUR (ORCPT ); Sun, 7 Mar 2021 22:20:17 -0500 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4Dv3T15rNxz7kKK; Mon, 8 Mar 2021 11:18:29 +0800 (CST) Received: from [10.174.178.215] (10.174.178.215) by smtp.huawei.com (10.3.19.203) with Microsoft SMTP Server (TLS) id 14.3.498.0; Mon, 8 Mar 2021 11:20:04 +0800 Subject: Re: [PATCH stable v5.10 0/7] arm64: Default to 32-bit wide ZONE_DMA To: Greg KH , Nicolas Saenz Julienne References: <20210303073319.2215839-1-jingxiangfeng@huawei.com> <9bc396116372de5b538d71d8f9ae9c3259f1002e.camel@suse.de> <827b317d7f5da6e048806922098291faacdb19f9.camel@suse.de> CC: , , , , , , , , , , , , , , , , , , , , , , , , , From: Jing Xiangfeng Message-ID: <604597E3.5000605@huawei.com> Date: Mon, 8 Mar 2021 11:20:03 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.215] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 2021/3/7 23:24, Greg KH wrote: > On Thu, Mar 04, 2021 at 04:09:28PM +0100, Nicolas Saenz Julienne wrote: >> On Thu, 2021-03-04 at 15:17 +0100, Greg KH wrote: >>> On Thu, Mar 04, 2021 at 03:05:32PM +0100, Nicolas Saenz Julienne wrote: >>>> Hi Greg. >>>> >>>> On Thu, 2021-03-04 at 14:46 +0100, Greg KH wrote: >>>>> On Wed, Mar 03, 2021 at 03:33:12PM +0800, Jing Xiangfeng wrote: >>>>>> Using two distinct DMA zones turned out to be problematic. Here's an >>>>>> attempt go back to a saner default. >>>>> What problem does this solve? How does this fit into the stable kernel >>>>> rules? >>>> We changed the way we setup memory zones in arm64 in order to cater for >>>> Raspberry Pi 4's weird DMA constraints: ZONE_DMA spans the lower 1GB of memory >>>> and ZONE_DMA32 the rest of the 32bit address space. Since you can't allocate >>>> memory that crosses zone boundaries, this broke crashkernel allocations on big >>>> machines. This series fixes all this by parsing the HW description and checking >>>> for DMA constrained buses. When not found, the unnecessary zone creation is >>>> skipped. >>> What kernel/commit caused this "breakage"? >> 1a8e1cef7603 arm64: use both ZONE_DMA and ZONE_DMA32 > Thanks for the info, all now queued up. There is a fix in 5.11. Please consider applying the following commit to 5.10.y: aed5041ef9a3 of: unittest: Fix build on architectures without CONFIG_OF_ADDRES Thanks > > greg k-h > . >