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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 C6FA5C433E0 for ; Thu, 4 Mar 2021 14:05:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 432C864F0A for ; Thu, 4 Mar 2021 14:05:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 432C864F0A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A996C6B0006; Thu, 4 Mar 2021 09:05:40 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A73A46B0008; Thu, 4 Mar 2021 09:05:40 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 95FDC6B000A; Thu, 4 Mar 2021 09:05:40 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0021.hostedemail.com [216.40.44.21]) by kanga.kvack.org (Postfix) with ESMTP id 7CD046B0006 for ; Thu, 4 Mar 2021 09:05:40 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id AA2F54DCB for ; Thu, 4 Mar 2021 14:05:39 +0000 (UTC) X-FDA: 77882364798.28.524D53A Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf25.hostedemail.com (Postfix) with ESMTP id 9E2F860014D6 for ; Thu, 4 Mar 2021 14:05:35 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E1DFBAAC5; Thu, 4 Mar 2021 14:05:34 +0000 (UTC) Message-ID: <9bc396116372de5b538d71d8f9ae9c3259f1002e.camel@suse.de> Subject: Re: [PATCH stable v5.10 0/7] arm64: Default to 32-bit wide ZONE_DMA From: Nicolas Saenz Julienne To: Greg KH , Jing Xiangfeng Cc: catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, rppt@kernel.org, lorenzo.pieralisi@arm.com, guohanjun@huawei.com, sudeep.holla@arm.com, rjw@rjwysocki.net, lenb@kernel.org, song.bao.hua@hisilicon.com, ardb@kernel.org, anshuman.khandual@arm.com, bhelgaas@google.com, guro@fb.com, robh+dt@kernel.org, stable@vger.kernel.org, linux-arm-kernel@lists.infradead.org, frowand.list@gmail.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, wangkefeng.wang@huawei.com Date: Thu, 04 Mar 2021 15:05:32 +0100 In-Reply-To: References: <20210303073319.2215839-1-jingxiangfeng@huawei.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-ahu+lDeVyw/D0YYfX8dU" User-Agent: Evolution 3.38.4 MIME-Version: 1.0 X-Stat-Signature: wengj1jtgrd3edaq4yudcumks4eoc53z X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 9E2F860014D6 Received-SPF: none (suse.de>: No applicable sender policy available) receiver=imf25; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: none/none X-HE-Tag: 1614866735-494907 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --=-ahu+lDeVyw/D0YYfX8dU Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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. >=20 > 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 mem= ory and ZONE_DMA32 the rest of the 32bit address space. Since you can't allocat= e memory that crosses zone boundaries, this broke crashkernel allocations on = big machines. This series fixes all this by parsing the HW description and chec= king for DMA constrained buses. When not found, the unnecessary zone creation is skipped. That said, I have no clue whether this falls or not into the stable kernel rules. Regards, Nicolas --=-ahu+lDeVyw/D0YYfX8dU Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEErOkkGDHCg2EbPcGjlfZmHno8x/4FAmBA6SwACgkQlfZmHno8 x/63Hwf/dPKsaiMfp4bHs98aLzm1BcfLltFqLOj2tjBqOYX6mUdfSKOkKZYGvyTs zZo2tT5ezbzEvU69CHgGmb6u3y4Q6PxDKqoL94xC+7RGwDrw4g4o0TZp67pcA/9d fUjl00sLvQUl6YYcajb6s0Ev97pb3XAyvAozXb3hfz36j/30mKbizfnxhn9gTZD0 lJ6Kp8Bmm0/weVW4Kj/SOnBk0J2WF7IwSxbJMKRz8k2ejAytoILh4PZ24V9c58Jw qhATgehwhDXk7hyZYQAKCr3pQD9fjWVVjU4/vbWXqBFvUhdmDSkCRAfYwZLJA1Cw lRRAL3P3GOOnCmGp7VZpexw14txF9Q== =1f1V -----END PGP SIGNATURE----- --=-ahu+lDeVyw/D0YYfX8dU--