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,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 D6723C4363A for ; Tue, 27 Oct 2020 17:44:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79E9A2054F for ; Tue, 27 Oct 2020 17:44:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=shutemov-name.20150623.gappssmtp.com header.i=@shutemov-name.20150623.gappssmtp.com header.b="JIM8871i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1821537AbgJ0Rol (ORCPT ); Tue, 27 Oct 2020 13:44:41 -0400 Received: from mail-lj1-f196.google.com ([209.85.208.196]:36781 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2896213AbgJ0ObC (ORCPT ); Tue, 27 Oct 2020 10:31:02 -0400 Received: by mail-lj1-f196.google.com with SMTP id x6so2018473ljd.3 for ; Tue, 27 Oct 2020 07:31:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=9yAnJkcJq8fJ842gCRIxyhnneLlwmBgpRa2BY7duk18=; b=JIM8871i1dAY6MSJz2tnV/FaZI+lJY9QwJ+/gDWCvRVezbv2K7KuEkac0kz9L4TnP+ up9BbSX57/v+XFqrwe9Nk6H3tY8lSWitihitPvKIbv/oYdwnx9UbEhaTF7lwTVSiWIgD ilkRy+vADEKZklPaM92sf7U2ZDEvt4vyQe17Hxsa1D9yAAFqXvrXeAG2Sryk8l69zJde pqvLQX2h+a+SXWzUCKBuRQLJgq79yjMzdWMayJKWo9486eawdqlCCvRGx82m7o4ryXkg Z8XiUFO+bNowsVwe89aLNK8ALBpx8ImxxN9i0ZU5L8514D85RUZwUUjty5eqn4+jgs2n dH+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=9yAnJkcJq8fJ842gCRIxyhnneLlwmBgpRa2BY7duk18=; b=URGDJwy3zNNDC974+U7B3JEdMLKypMuCzQGGxvuFXKfu6K4cA037fdgZkMVIilKv9w IM56LrgKfAVSY8WlLaRMC4cHwMOEjhMfsHag2f1UsEcKrBLx7Lv5T8kLwv/6QlW07Gd7 qNcxvDOW6WBVfjqFQM09OQRmdlfE7twarYhrCByUje6rDpFzIGpoNoxjLNqT8XLbG62b xUmHKf5RgjvTizzsIjOaNI/RnDM/X2+Fw4RbioTOg+hyV0G0lEV/2i4QTLoc63JbhI7+ +GMB5WjKdgklRwpIz8+VZC+ZON1pb1lSvbx26a2wipgLamDdASYoc952JTKR2BD1RgjC CI3A== X-Gm-Message-State: AOAM533LwKT1HXXgvw2ql0Aypm8Jl3S0J0Nqw0cCE0z1TBHIGj2p5vwQ qZsHi/9QZsm13DEpDVTS8EvKZx55aKxk6A== X-Google-Smtp-Source: ABdhPJxE9wm01oT28amSRCIGKy3EHdyNrPGPuB+JBcPp7uz1dYSw974Isdqrkp2wPm37df4UQ++3rA== X-Received: by 2002:a2e:6a19:: with SMTP id f25mr1306896ljc.386.1603809060636; Tue, 27 Oct 2020 07:31:00 -0700 (PDT) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id b10sm191716lfd.263.2020.10.27.07.31.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Oct 2020 07:31:00 -0700 (PDT) Received: by box.localdomain (Postfix, from userid 1000) id 54474103677; Tue, 27 Oct 2020 17:31:02 +0300 (+03) Date: Tue, 27 Oct 2020 17:31:02 +0300 From: "Kirill A. Shutemov" To: Arvind Sankar Cc: x86@kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , Kees Cook , Joerg Roedel Subject: Re: RFC x86/boot/64: BOOT_PGT_SIZE definition for compressed kernel Message-ID: <20201027143102.ugco5dmixu66fjsc@box> References: <20201025004158.GA767345@rani.riverdale.lan> <20201027124007.xkkseswwgerlzlsl@box> <20201027131617.GA1743199@rani.riverdale.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201027131617.GA1743199@rani.riverdale.lan> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 27, 2020 at 09:16:17AM -0400, Arvind Sankar wrote: > The #PF handler is already there now with the SEV-ES series, but I agree > it would still complicate things. It's simpler to just increase > BOOT_PGT_SIZE and make it unconditional (i.e. bump it to say 32 or 64 > even if !KASLR). It's @nobits anyway so it would not increase the size > of the bzImage, just require a slightly larger memory allocation by the > bootloader. I guess it's fine. But I'm worried we leave the picture in the same fragile state. We still rely on the magic number. -- Kirill A. Shutemov