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, URIBL_BLOCKED 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 1BFBBC4363D for ; Fri, 25 Sep 2020 10:29:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C785922B2D for ; Fri, 25 Sep 2020 10:29:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727151AbgIYK3Y (ORCPT ); Fri, 25 Sep 2020 06:29:24 -0400 Received: from mga12.intel.com ([192.55.52.136]:21115 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727132AbgIYK3Y (ORCPT ); Fri, 25 Sep 2020 06:29:24 -0400 IronPort-SDR: vuOcnjED3Fx0CeCEZsVaptiom6ZqPLQHOh0joeyQC4aDCqcOWpKtr2EeWc2uTeTLwOfWR+thi1 OgKw3v/T6uaQ== X-IronPort-AV: E=McAfee;i="6000,8403,9754"; a="140904959" X-IronPort-AV: E=Sophos;i="5.77,301,1596524400"; d="scan'208";a="140904959" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Sep 2020 03:29:24 -0700 IronPort-SDR: 6yOz4t4UbYext8bf560KO5M7v1plRNU+tSJgTyJBDE1vo7EE4RE7RggBMPB2j+H49EhzuSE9RH yhPJD8TzwMHA== X-IronPort-AV: E=Sophos;i="5.77,301,1596524400"; d="scan'208";a="455766872" Received: from tjhenson-mobl.amr.corp.intel.com (HELO localhost) ([10.252.48.117]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Sep 2020 03:29:22 -0700 Date: Fri, 25 Sep 2020 13:29:20 +0300 From: Jarkko Sakkinen To: Ard Biesheuvel Cc: linux-integrity , Linux Kernel Mailing List , Peter Huewe , Jason Gunthorpe Subject: Re: [PATCH] tpm: of: avoid __va() translation for event log address Message-ID: <20200925102920.GA180915@linux.intel.com> References: <20200922094128.26245-1-ardb@kernel.org> <20200925055626.GC165011@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Fri, Sep 25, 2020 at 09:00:56AM +0200, Ard Biesheuvel wrote: > On Fri, 25 Sep 2020 at 07:56, Jarkko Sakkinen > wrote: > > > > On Tue, Sep 22, 2020 at 11:41:28AM +0200, Ard Biesheuvel wrote: > > > The TPM event log is provided to the OS by the firmware, by loading > > > it into an area in memory and passing the physical address via a node > > > in the device tree. > > > > > > Currently, we use __va() to access the memory via the kernel's linear > > > map: however, it is not guaranteed that the linear map covers this > > > particular address, as we may be running under HIGHMEM on a 32-bit > > > architecture, or running firmware that uses a memory type for the > > > event log that is omitted from the linear map (such as EfiReserved). > > > > Makes perfect sense to the level that I wonder if this should have a > > fixes tag and/or needs to be backported to the stable kernels? > > > > AIUI, the code was written specifically for ppc64, which is a > non-highmem, non-EFI architecture. However, when we start reusing this > driver for ARM, this issue could pop up. > > The code itself has been refactored a couple of times, so I think it > will require different versions of the patch for different generations > of stable kernels. > > So perhaps just add Cc: , and wait and see how > far back it applies cleanly? Yeah, I think I'll cc it with some note before the diffstat. I'm thinking to cap it to only 5.x kernels (at least first) unless it is dead easy to backport below that. > > This is a really great catch! > > > > I'm a bit late of my PR a bit because of SGX upstreaming madness > > (sending v39 soon). If you can answer to my question above, I can do > > that nitpick change to patch and get it to my v5.10 PR. > > > > Yes, please. Great, will do, thanks again for fixing this issue! /Jarkko