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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43EA3C433FE for ; Tue, 1 Nov 2022 15:40:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231348AbiKAPku (ORCPT ); Tue, 1 Nov 2022 11:40:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229877AbiKAPks (ORCPT ); Tue, 1 Nov 2022 11:40:48 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFD16BCB1 for ; Tue, 1 Nov 2022 08:40:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1667317247; x=1698853247; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=PdiefJ/kTbBD/wXr6en4XMshbMyVBy16hir1aWLoRr8=; b=ZAryAoXwRSNYpFrzxGzzKe2MgdibXt2y23KHncxTghxKkEtaqIy+j88W KiG+g1WpFTzoBadO2NGUvq8t31z3JIw2iSQFoE1u9OQhrdLHyLL5lPzEb tS7K9HiE1xGCqCuU+0JeIH+kHiPINKAOQg1AgslqC4QUO4IpTHbOg+vBx USOJbcnich6/tW5HHSAtEEIZ9XDw74gNqnhjTi/PpRAn8MOdDDpMxY99j llXPpEOvE3al3E/TOpx7q+m4G0PU8QtaQcSlyDpjwLwqGKvLUiHqwIzHA arYlUc2zuLK26xcw3Ee3GeOyaiplMP1fh+eAJw7Pejt0mFkq+LYVqOAB7 w==; X-IronPort-AV: E=McAfee;i="6500,9779,10518"; a="306782398" X-IronPort-AV: E=Sophos;i="5.95,231,1661842800"; d="scan'208";a="306782398" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Nov 2022 08:40:47 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10518"; a="739372473" X-IronPort-AV: E=Sophos;i="5.95,231,1661842800"; d="scan'208";a="739372473" Received: from irvmail001.ir.intel.com ([10.43.11.63]) by fmsmga002.fm.intel.com with ESMTP; 01 Nov 2022 08:40:45 -0700 Received: from newjersey.igk.intel.com (newjersey.igk.intel.com [10.102.20.203]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id 2A1FehK2014382; Tue, 1 Nov 2022 15:40:43 GMT From: Alexander Lobakin To: Jiri Slaby Cc: Alexander Lobakin , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , "Peter Zijlstra (Intel)" , Tony Luck , Kees Cook , Masahiro Yamada , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] x86/boot: robustify calling startup_{32,64}() from the decompressor code Date: Tue, 1 Nov 2022 16:38:34 +0100 Message-Id: <20221101153834.975871-1-alexandr.lobakin@intel.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <39ac78ea-1ee5-8911-1208-c56e57df7338@kernel.org> References: <20221031151047.167288-1-alexandr.lobakin@intel.com> <20221031151047.167288-2-alexandr.lobakin@intel.com> <0fcbedf6-3eb5-75cd-cdd9-24582f70cc64@kernel.org> <39ac78ea-1ee5-8911-1208-c56e57df7338@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jiri Slaby Date: Tue, 1 Nov 2022 07:50:04 +0100 > On 01. 11. 22, 7:47, Jiri Slaby wrote: > > Tested-by: Jiri Slaby > > FWIW that means: tested with gcc-lto which deliberately stores > startup_64() randomly, not to the beginning of vmlinux. Yeah, you never know. After rebasing on top of 6.1-rc1 my FG-KASLR series stopped booting, I found out that the combo of that head-object-list.txt + -ffunction-sections (but for Asm) also made startup_64() appear in random parts of .head.text. Re head removal -- that would be awesome, but currently from what I've tried during the development, there's a lot of stuff to be redone, the compressor code sometimes just doesn't want to work if you play with .head.text too much. Will see. > > -- > js > suse labs Thanks, Olek