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=-17.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 6F17BC47082 for ; Tue, 8 Jun 2021 17:30:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F933613AE for ; Tue, 8 Jun 2021 17:30:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233245AbhFHRbw (ORCPT ); Tue, 8 Jun 2021 13:31:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:59608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231652AbhFHRbv (ORCPT ); Tue, 8 Jun 2021 13:31:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8EA3B61378; Tue, 8 Jun 2021 17:29:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623173398; bh=ma/CkFfb8CYaaDcX25dR9NFonTv/wOGFyGfkm75Kj9Y=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=VbARVNu/BDv7MOreXdH0h0CjHdMLUOauVp/AeplxCuwYNJfohMxtKJWhy8RaPPtQ0 dCplQ8K+KqbASS0q/VrnUAClykw8RFvI/nvJdSIOQ/o27JX68HdKEQkDqm18fze5lq zk92iaQ7GwSSAueUAqMKpRfGSmGvPaD2ZajXpgn/LC3jDf5umXHUyLxyik0BN6QYFg RqSji2MPY67nmh80t4F1wvVMpYSCJmlJVPV3ITkci84klRjfGBu+TnU+iHu9afBMm0 hffBmnxfZlrwmJMmIrglrEN3Es3tjtkpSDNjLAgKwern6vhY1nY0Rgiiy0VyygDxUX s5Riljchq/j0Q== Subject: Re: [PATCH v3 16/16] objtool,x86: Rewrite retpoline thunk calls To: Peter Zijlstra Cc: Nick Desaulniers , =?UTF-8?B?RsSBbmctcnXDrCBTw7JuZw==?= , Josh Poimboeuf , lma@semihalf.com, Guenter Roeck , Juergen Gross , lb@semihalf.com, LKML , mbenes@suse.com, =?UTF-8?Q?Rados=c5=82aw_Biernacki?= , upstream@semihalf.com, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , clang-built-linux , Sami Tolvanen References: <20210604205018.2238778-1-ndesaulniers@google.com> <20210604235046.w3hazgcpsg4oefex@google.com> From: Nathan Chancellor Message-ID: Date: Tue, 8 Jun 2021 10:29:56 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/8/2021 10:22 AM, Peter Zijlstra wrote: > On Tue, Jun 08, 2021 at 09:58:03AM -0700, Nathan Chancellor wrote: >> On 6/7/2021 1:54 PM, 'Nick Desaulniers' via Clang Built Linux wrote: >>> On Mon, Jun 7, 2021 at 2:46 AM Peter Zijlstra wrote: >>>> >>> >>> Thanks, the below diff resolves the linker error reported in >>> https://github.com/ClangBuiltLinux/linux/issues/1388 >>> >>> Both readelf implementations seem happy with the results, too. >>> >>> Tested-by: Nick Desaulniers >>> >>> Nathan, >>> Can you please test the below diff and see if that resolves your boot >>> issue reported in: >>> https://github.com/ClangBuiltLinux/linux/issues/1384 >> >> Unfortunately, it does not appear to resolve that issue. >> >> $ git log -2 --decorate=no --oneline >> eea6a9d6d277 Peter's fix >> 614124bea77e Linux 5.13-rc5 >> >> $ strings /mnt/c/Users/natec/Linux/kernel-investigation | grep microsoft >> 5.13.0-rc5-microsoft-standard-WSL2-00001-geea6a9d6d277 >> (nathan@archlinux-ax161) #3 SMP Tue Jun 8 09:46:19 MST 2021 >> >> My VM still never makes it to userspace. > > Since it's a VM, can you use the gdb-stub to ask it where it's stuck? > Unfortunately, this is the VM provided by the Windows Subsystem for Linux so examining it is nigh-impossible :/ I am considering bisecting the transforms that objtool does to try and figure out the one that causes the machine to fail to boot or try to reproduce in a different hypervisor, unless you have any other ideas. Cheers, Nathan