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=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 09D91C433F5 for ; Sat, 18 Sep 2021 08:37:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9917E60F5B for ; Sat, 18 Sep 2021 08:37:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 9917E60F5B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 251536B0071; Sat, 18 Sep 2021 04:37:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1DA736B0072; Sat, 18 Sep 2021 04:37:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 07AC9900002; Sat, 18 Sep 2021 04:37:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0065.hostedemail.com [216.40.44.65]) by kanga.kvack.org (Postfix) with ESMTP id E7B9D6B0071 for ; Sat, 18 Sep 2021 04:37:23 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 6BC371808F562 for ; Sat, 18 Sep 2021 08:37:23 +0000 (UTC) X-FDA: 78600039966.09.662E2FE Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf01.hostedemail.com (Postfix) with ESMTP id 112A35067B3F for ; Sat, 18 Sep 2021 08:37:22 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 1CFF061244; Sat, 18 Sep 2021 08:37:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631954242; bh=5rf6GNCOG0zu4pGRCwF+YbXBBU6EolzS6vCH7c+IvKs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Yxwy2HNMi9dHgQj9qCv86MXaNJJQWiUl6Ksd+njViNwepR7JvlYUW8CuXfggEoyh1 1kjY23zZPcRybB1El/UDq0QsV7kCY4jWKNWZjepFw+IZ88p2Jsk6rsbJ7zuYHhNCwG 3Tjn+d5c2zpVrD7ebKQ/1M8Bog6vuuATN1lzFh9U/yIjtxbtAPKtASHMjiO3YQ7bNC Ozj+nv19D8498bWxx85KY23BA62zLoM6nwgUujOiQCP/852Y5mTI3M1QCogtYlPkWP DUJOdp0voj9dTCR4xtk1S/KJ8rLJgQvCx//iI4e2CNUJlrLcWU9prfnhsNnzTLFGLw HpsMCtbBGCEag== Date: Sat, 18 Sep 2021 11:37:15 +0300 From: Mike Rapoport To: Christoph Hellwig Cc: Catalin Marinas , David Hildenbrand , Robin Murphy , Alex Bee , Will Deacon , Andrew Morton , Anshuman Khandual , Linux Kernel Mailing List , linux-mm@kvack.org, Linux ARM Subject: Re: [BUG 5.14] arm64/mm: dma memory mapping fails (in some cases) Message-ID: References: <20210824173741.GC623@arm.com> <0908ce39-7e30-91fa-68ef-11620f9596ae@arm.com> <60a11eba-2910-3b5f-ef96-97d4556c1596@redhat.com> <20210825102044.GA3420@arm.com> <20210918051843.GA16104@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210918051843.GA16104@lst.de> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 112A35067B3F X-Stat-Signature: 6qjqxdakepxx8go3q56ym77c3kq7w3mo Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Yxwy2HNM; spf=pass (imf01.hostedemail.com: domain of rppt@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-HE-Tag: 1631954242-351191 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: On Sat, Sep 18, 2021 at 07:18:43AM +0200, Christoph Hellwig wrote: > On Sat, Sep 18, 2021 at 12:22:47AM +0300, Mike Rapoport wrote: > > I did some digging and it seems that the most "generic" way to check if a > > page is in RAM is page_is_ram(). It's not 100% bullet proof as it'll give > > false negatives for architectures that do not register "System RAM", but > > those are not using dma_map_resource() anyway and, apparently, never would. > > The downside of page_is_ram is that it looks really expensiv for > something done at dma mapping time. Indeed :( But pfn_valid is plain wrong... I'll keep digging. -- Sincerely yours, Mike.