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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 89E5CC433EF for ; Fri, 15 Oct 2021 05:51:11 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (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 2E073611C3 for ; Fri, 15 Oct 2021 05:51:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 2E073611C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id E32FC83B37; Fri, 15 Oct 2021 05:51:10 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id v3PH-Y4sZiO2; Fri, 15 Oct 2021 05:51:10 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp1.osuosl.org (Postfix) with ESMTPS id 96B0183B32; Fri, 15 Oct 2021 05:51:09 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 6BAB2C0011; Fri, 15 Oct 2021 05:51:09 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id A95D5C000D for ; Fri, 15 Oct 2021 05:51:07 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 7BD32404FD for ; Fri, 15 Oct 2021 05:51:07 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id oU9A9JqHvkPU for ; Fri, 15 Oct 2021 05:51:02 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by smtp4.osuosl.org (Postfix) with ESMTPS id AC5E8404F6 for ; Fri, 15 Oct 2021 05:51:02 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10137"; a="251298657" X-IronPort-AV: E=Sophos;i="5.85,374,1624345200"; d="scan'208";a="251298657" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2021 22:51:02 -0700 X-IronPort-AV: E=Sophos;i="5.85,374,1624345200"; d="scan'208";a="481583984" Received: from akleen-mobl1.amr.corp.intel.com (HELO [10.209.55.104]) ([10.209.55.104]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2021 22:51:00 -0700 Message-ID: Date: Thu, 14 Oct 2021 22:50:59 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [PATCH v5 16/16] x86/tdx: Add cmdline option to force use of ioremap_host_shared Content-Language: en-US To: "Michael S. Tsirkin" References: <20211009003711.1390019-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20211009003711.1390019-17-sathyanarayanan.kuppuswamy@linux.intel.com> <20211009070132-mutt-send-email-mst@kernel.org> <8c906de6-5efa-b87a-c800-6f07b98339d0@linux.intel.com> <20211011075945-mutt-send-email-mst@kernel.org> <9d0ac556-6a06-0f2e-c4ff-0c3ce742a382@linux.intel.com> <20211011142330-mutt-send-email-mst@kernel.org> <4fe8d60a-2522-f111-995c-dcbefd0d5e31@linux.intel.com> <20211012165705-mutt-send-email-mst@kernel.org> <20211012171846-mutt-send-email-mst@kernel.org> From: Andi Kleen In-Reply-To: <20211012171846-mutt-send-email-mst@kernel.org> Cc: Kuppuswamy Sathyanarayanan , Kuppuswamy Sathyanarayanan , Peter Zijlstra , linux-pci@vger.kernel.org, linux-mips@vger.kernel.org, James E J Bottomley , Dave Hansen , Peter H Anvin , sparclinux@vger.kernel.org, Thomas Gleixner , Andrea Arcangeli , Jonathan Corbet , Helge Deller , x86@kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, Arnd Bergmann , Tony Luck , Borislav Petkov , Andy Lutomirski , Josh Poimboeuf , Bjorn Helgaas , Dan Williams , virtualization@lists.linux-foundation.org, Richard Henderson , Thomas Bogendoerfer , linux-parisc@vger.kernel.org, Sean Christopherson , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, Paolo Bonzini , "David S . Miller" , Kirill Shutemov X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" > I thought you basically create an OperationRegion of SystemMemory type, > and off you go. Maybe the OSPM in Linux is clever and protects > some memory, I wouldn't know. I investigated this now, and it looks like acpi is using ioremap_cache(). We can hook into that and force non sharing. It's probably safe to assume that this is not used on real IO devices. I think there are still some other BIOS mappings that use just plain ioremap() though. -Andi _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization