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 C8CCEC41513 for ; Mon, 31 Jul 2023 11:19:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230363AbjGaLTp (ORCPT ); Mon, 31 Jul 2023 07:19:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33164 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230002AbjGaLTn (ORCPT ); Mon, 31 Jul 2023 07:19:43 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87AC8171A for ; Mon, 31 Jul 2023 04:18:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690802318; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Feb3SbI628V0M+Xl6cXNHTwh1emqN1pCsroF1cMMhXw=; b=DkoSD4M4j0SVdH6bDKkPMS+u5i9MD6sz33fSdRvQpOqvOHdBV8g67wAGV4vgZI4xuMpaJC s3MoizijuMWMdxrAAv44NVx6/MBZqQX2hpNkiGqLw6aFGdg3KHmVrf0rhPkqBHYzr3TzLf uk2UUhd45t6JM0ZNxdyj40MED3JuSr4= Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-230-Mt-nzKkYNISK4WyBw2Pg4w-1; Mon, 31 Jul 2023 07:18:35 -0400 X-MC-Unique: Mt-nzKkYNISK4WyBw2Pg4w-1 Received: by mail-qt1-f199.google.com with SMTP id d75a77b69052e-406afc93066so39029801cf.0 for ; Mon, 31 Jul 2023 04:18:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690802315; x=1691407115; h=mime-version:message-id:date:references:in-reply-to:subject:cc:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Feb3SbI628V0M+Xl6cXNHTwh1emqN1pCsroF1cMMhXw=; b=TTRcGa8CNHGQN/OD/ZV/CsQz7Q44/OZrIF+g4bbxg+EmzEETocDAr/GS8iKrmpZolq aIsD2u3xZ1Hy0XXu1VAiQ7N1Zss/zJBlE21k9t6s26V4jROvhft/N5i7i1okuqD6pNFh htTwQ0GKA/nn76TnzfXklWApBtSYt1h62qH0I67cOt1jw+bDhVhzhUiEjosinw7JGBbo SIf97+nAo27dVL+PHE2+d3Lbk0EGe5At2pvuWCcofjekpeQyJ/xJa7hUiXaXq1taASOH LfgSK6TZlPWlQtJ5PC7nnD5KFSOSFqxc7XLaUN6d0sa9hy/SFmj6zYfB5r24b3zJf5nh t+pQ== X-Gm-Message-State: ABy/qLaN/wykSsVebfV6Qo97I8hH9pd0qNfJYPQ8+gJoY+tWxwBqYGFQ shyDtgaL/q54O82XUa512CHfDsbupVOI3B4eZ3u8bjPx9w94gF5AoNZp+1h3wv2AnH0td9crAz+ CYx501UrBOptaEDtGtTGJouW/rKFtEN6r X-Received: by 2002:a05:622a:1806:b0:403:b23f:9e16 with SMTP id t6-20020a05622a180600b00403b23f9e16mr13377211qtc.2.1690802314883; Mon, 31 Jul 2023 04:18:34 -0700 (PDT) X-Google-Smtp-Source: APBJJlEehrZuAEoVbTnlaVgIfddlc4rg89Sd70WHq1FBXragdFZy0TviERBFx02bWZYfpI2p+8TwzA== X-Received: by 2002:a05:622a:1806:b0:403:b23f:9e16 with SMTP id t6-20020a05622a180600b00403b23f9e16mr13377176qtc.2.1690802314653; Mon, 31 Jul 2023 04:18:34 -0700 (PDT) Received: from vschneid.remote.csb ([149.12.7.81]) by smtp.gmail.com with ESMTPSA id e21-20020ac85995000000b003fde3d63d22sm3385798qte.69.2023.07.31.04.18.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 Jul 2023 04:18:33 -0700 (PDT) From: Valentin Schneider To: Josh Poimboeuf Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, x86@kernel.org, rcu@vger.kernel.org, linux-kselftest@vger.kernel.org, Josh Poimboeuf , Steven Rostedt , Masami Hiramatsu , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , Juri Lelli , Daniel Bristot de Oliveira , Marcelo Tosatti , Yair Podemsky Subject: Re: [RFC PATCH v2 12/20] objtool: Warn about non __ro_after_init static key usage in .noinstr In-Reply-To: <20230728160247.multb2csnpa22fgx@treble> References: <20230720163056.2564824-1-vschneid@redhat.com> <20230720163056.2564824-13-vschneid@redhat.com> <20230728160247.multb2csnpa22fgx@treble> Date: Mon, 31 Jul 2023 12:18:10 +0100 Message-ID: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org On 28/07/23 11:02, Josh Poimboeuf wrote: > On Thu, Jul 20, 2023 at 05:30:48PM +0100, Valentin Schneider wrote: >> Later commits will depend on having no runtime-mutable text in early entry >> code. (ab)use the .noinstr section as a marker of early entry code and warn >> about static keys used in it that can be flipped at runtime. > > Similar to my comment on patch 13, this could also use a short > justification for adding the feature, i.e. why runtime-mutable text > isn't going to be allowed in .noinstr. > > Also, please add a short description of the warning (and why it exists) > to tools/objtool/Documentation/objtool.txt. > I had missed this, thanks for the pointer. > -- > Josh