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=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 65B4DC432BE for ; Fri, 27 Aug 2021 07:42:54 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 37F3B60FD8 for ; Fri, 27 Aug 2021 07:42:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 37F3B60FD8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=1/Dz+QAevfyWm9sTBVaAq5P2KB8NqxzJ/0vBOyYPebs=; b=wI7okILTicHTXC 2/v5k1Kd4rDoaQ11zreQ6kQZDjrgcQqaV0ALwjRyMksKHy73QRUKE5urwNscbEmUdZN7jw8fqGGFP HAvV8GYAh4tI+TjP5zN7HskBgfDGFn7j1n3Mn2sxE/H/oM+69+h/6+O+k+9Ls06JTxnLLybJar8EE 2O9/q3Oj6znf39dOJNs19tFHSuaHMpT1ubX06wy4AGLnsKO5RtrhNW66ySV1zC1rEx7NfSTHrDG3G A19jTSOxt0svChvkIAnlTZMe+oSv7qp9MDTP6PMtYz+3e5mfQ/02UTbzvPcoryLWT1nFCVYXki7Rk YGxnTE/kQrY+XJ4+4wNg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJWTq-00Bs5H-Km; Fri, 27 Aug 2021 07:40:50 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJWTn-00Bs44-86 for linux-arm-kernel@lists.infradead.org; Fri, 27 Aug 2021 07:40:48 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 001846736F; Fri, 27 Aug 2021 09:40:41 +0200 (CEST) Date: Fri, 27 Aug 2021 09:40:41 +0200 From: Christoph Hellwig To: Linus Torvalds Cc: Will Deacon , Christoph Hellwig , Catalin Marinas , Linux ARM , Linux Kernel Mailing List , Android Kernel Team Subject: Re: [GIT PULL] arm64 fix for 5.14 Message-ID: <20210827074041.GA24309@lst.de> References: <20210826131747.GE26318@willie-the-truck> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210827_004047_489331_52084F69 X-CRM114-Status: GOOD ( 15.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Aug 26, 2021 at 11:41:34AM -0700, Linus Torvalds wrote: > "pfn_valid()" is more about whether you can do a "pfn_to_page()" lookup on it. > > II get the feeling that the dma-mapping code should allow pages that > are PageReserved() to be mapped - they aren't "ram" in the kernel > sense. > > Perhaps also make sure it's not the zero page (which is > PageReserved(), but most definitely RAM). > > In a PC world that would be (for example) the legacy PCI space at > 0xa0000-0xfffff, but I could easily imagine other platforms having > other situations. So what would be the correct check for "this is not actually page backed normal RAM"? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel