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=0.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,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 1DD71C3F2C6 for ; Sat, 29 Feb 2020 09:24:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E28A824677 for ; Sat, 29 Feb 2020 09:24:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582968273; bh=cGBBMVSgNEa2yMATVwA8/LRDx3d3/mLF9cUosPH04Dg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=dpNf/qK4SweYbYPOImGxcJM7NSSj4asDYwZTwlV0yuY78sxZYF3DcZMmeQ0rUlP9c hZN64f7JQbqC2Axd63HJXhsmDiQXRtGAEC7BtvHQr7Z0bVRY9sX1tDQsLQusxWaQhR 3supIlyEDbvdUoFoVM2juYwlrjtPY0mJfgP3TqLs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726857AbgB2JYb (ORCPT ); Sat, 29 Feb 2020 04:24:31 -0500 Received: from mail-wr1-f68.google.com ([209.85.221.68]:42820 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726751AbgB2JYb (ORCPT ); Sat, 29 Feb 2020 04:24:31 -0500 Received: by mail-wr1-f68.google.com with SMTP id p18so6075200wre.9; Sat, 29 Feb 2020 01:24:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=RgPJE0orJQVDrDLEaPJ8R2RxW8F5htMBVkLJo9I+3vI=; b=o9rkUgC3sZYDJqLH0G98KAbq5NAH7w8L5tbrS2uN5TzpAoyRCzhVio6e2iwYrB13dY xHsrTSzVBewKcPJcBcLzDrgOToNImEQeZ9joKizsBvGASOzPAiW8/NWryBSUuGRig3Gu NW2y73yAVN4drVh9it/+OBI0+f7gcI7ZM4Y/oiyKjLMWsAYlrMTv+XgxrdYFQ+fxT9tr n0aG94hIH5s6TkVWYbIlamSVDTv2ES+8PkP3zujOXMJ38DcbXtkIt4HCcpsjUcajFbY4 JjFcnwg7F8iJT1AT8g6lvnSohzgu6kTK9M6zQqr40j1ST8e7grDp2i6htBLXaxgQH9Wv x1nw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=RgPJE0orJQVDrDLEaPJ8R2RxW8F5htMBVkLJo9I+3vI=; b=jOPr61QL0QiUaEzpPuWwmFKstJ1f+Ll3dj4VA+os+ppsN85rOuOX6Gz0g0Fd+NN54r QK6rC/kUOsZaBa9WPWh6GLlrVufwT6BvaJf2qisGvWis/E/rGZ3f9Z+XUKRD2+iMD1Ha I9oBDq9e8f0PCykDzzkyR34qslLkLUEv8z8YRdCJ5tuJUqW2SvM6QeFbHAw8qCbhjhuC VK6OfPIdhiGk8x2YDYMhOHyXU3/58h6jVsDFl4mteSzQBqPM0Q4GL9S9QBbc3zIDiw5N jRBKj8dYeq2RsxH18GU8WvTNiQ3Jm4hmi7nGMp95dj1/uQ7nRVi2oj4YUSdXd/65mEwv h67A== X-Gm-Message-State: APjAAAWcZemcRXjr2pvPCdzjycZslsa9ABUJyFbXZRc0kS58NRLxcgCw qRRG34f9ht9c/BC0bT4vIf4= X-Google-Smtp-Source: APXvYqypQZFf++sh1JdwJcb+KL95+X3s+ht196vQUdpvCNcMCeFhfMHU9OUnkaQTMr1064b6VZ1vPA== X-Received: by 2002:a5d:4384:: with SMTP id i4mr5183282wrq.396.1582968268971; Sat, 29 Feb 2020 01:24:28 -0800 (PST) Received: from gmail.com (54033286.catv.pool.telekom.hu. [84.3.50.134]) by smtp.gmail.com with ESMTPSA id p17sm14011569wre.89.2020.02.29.01.24.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 29 Feb 2020 01:24:27 -0800 (PST) Date: Sat, 29 Feb 2020 10:24:25 +0100 From: Ingo Molnar To: Arvind Sankar Cc: Ard Biesheuvel , linux-efi , Thomas Gleixner , the arch/x86 maintainers , Linux Kernel Mailing List , Borislav Petkov Subject: Re: [PATCH v2 1/1] x86/boot/compressed: Fix reloading of GDTR post-relocation Message-ID: <20200229092425.GB92847@gmail.com> References: <20200226204515.2752095-1-nivedita@alum.mit.edu> <20200226230031.3011645-2-nivedita@alum.mit.edu> <20200227081229.GA29411@gmail.com> <20200227151643.GA3498170@rani.riverdale.lan> <20200227155421.GA3507597@rani.riverdale.lan> <20200227180305.GA3598722@rani.riverdale.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200227180305.GA3598722@rani.riverdale.lan> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Arvind Sankar wrote: > On Thu, Feb 27, 2020 at 06:47:55PM +0100, Ard Biesheuvel wrote: > > > > Interesting. I am going to rip most of the EFI handover protocol stuff > > out of OVMF, since it is mostly unnecessary, and having the PE/COFF > > loader put the image in the correct place right away is a nice > > complimentary improvement to that. (Note that the OVMF implementation > > of the EFI handover protocol does not currently honor the preferred > > address from the setup header anyway) > > Yeah, for my testing I'm running the image from the EFI shell, which > enters via PE entry point and honors the pref address. So with KASLR, which is the distro default on most x86 distros, we'll relocate the kernel to another address anyway, right? But telling the bootloader the preferred address would avoid any relocation overhead even in this case, right? Thanks, Ingo