From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E6702C82 for ; Tue, 18 Jan 2022 19:23:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1642533783; 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=szFzYuqp/rVABkm8mkSgMpFZFDViwmtCeMvEqr1ilK0=; b=aX1IXfXmQJFF8VIUSpouTMpgF9g+Kraim2peX5SqvRofhNvFX7R2gz5LjbbmbSExrQblf+ GNEPMn9SZlALcsl+CBLyKZo63mZTLWTz2itTD0ri8eL4FJtWH52zxVD7vGOJ/oZhjzgx4t 4ACfDcitZK+SJ6in1I/GhcUrTf5jMsg= Received: from mail-ot1-f72.google.com (mail-ot1-f72.google.com [209.85.210.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-582-bcSCp6fFPFmMMY1t-uNAPg-1; Tue, 18 Jan 2022 14:23:00 -0500 X-MC-Unique: bcSCp6fFPFmMMY1t-uNAPg-1 Received: by mail-ot1-f72.google.com with SMTP id 49-20020a9d08b4000000b0059bd1411628so117999otf.8 for ; Tue, 18 Jan 2022 11:23:00 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=szFzYuqp/rVABkm8mkSgMpFZFDViwmtCeMvEqr1ilK0=; b=f/KSvv24iPG/Uq2X71AYlb6MKJBgzFY3VW51VvFRjCnJ0pBCQTel1DCx2r0QXH+BEi XeUYd/EqAhe3aBZxiHG6/kxlsJWSjEtD/PEIMss4cTo6mkZC9Q1axeZT7CB3tpR+3XHO RKa2L+zHe0dgFMITnUfw0tVD1citmgTatUJx0WTlciiSu2h/shT16M+Y615qenV5ggSx OsANbBG+GkybjPZdYeVy4dPjoPTluzslVto2iA7b/6A6tPgUJo8L13vroU5IfcYwk/s4 hF9goQmDdtYEzDy30yYyIXWafsaUrjm6UnuF7AlytxbEH6iB6sWocLrr9q1iL05ZVvtV a29w== X-Gm-Message-State: AOAM531tNMyNfp5b2i9r9/qVNMhwT1dIJVuuaPl0rgxHPNqijklSqATG v0khjGvwRZBkE/S2QTJdG1L0a1DHQLhaAI70iUVKJFLI0SKoMNp4r6NwO/XRon1wl2oA4STLe0o UbnZf3V6J0fTsQQ== X-Received: by 2002:a05:6830:148f:: with SMTP id s15mr12549734otq.242.1642533779971; Tue, 18 Jan 2022 11:22:59 -0800 (PST) X-Google-Smtp-Source: ABdhPJwzr0wpP0kkTCgrhkGxkaIaWoXrzgt8LpYDiF/kTrxf2zstxk5uqrspsrdw765/b9E+vg16lA== X-Received: by 2002:a05:6830:148f:: with SMTP id s15mr12549720otq.242.1642533779776; Tue, 18 Jan 2022 11:22:59 -0800 (PST) Received: from treble ([2600:1700:6e32:6c00::c]) by smtp.gmail.com with ESMTPSA id i25sm7472390otl.8.2022.01.18.11.22.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jan 2022 11:22:59 -0800 (PST) Date: Tue, 18 Jan 2022 11:22:56 -0800 From: Josh Poimboeuf To: Borislav Petkov Cc: Nick Desaulniers , Vasily Gorbik , Linus Torvalds , Ingo Molnar , Dave Hansen , Thomas Gleixner , Peter Zijlstra , Luc Van Oostenryck , x86@kernel.org, llvm@lists.linux.dev, linux-sparse@vger.kernel.org, linux-kernel@vger.kernel.org, kernel test robot , Nathan Chancellor Subject: Re: [PATCH] objtool: prefer memory clobber & %= to volatile & __COUNTER__ Message-ID: <20220118192256.jzk5dnceeusq7x7u@treble> References: <20220114010526.1776605-1-ndesaulniers@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jpoimboe@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline On Sun, Jan 16, 2022 at 02:32:59PM +0100, Borislav Petkov wrote: > so I like the local label and how it is more readable this way. > > So, provided the memory clobber works (I wonder here if Josh has some > concrete failing cases which could be tested with your version) and > after the nitpicks have been addressed > > Acked-by: Borislav Petkov I think Nick was already able to recreate the original issue. I'll run it through some more testing. I wanted to make this change years ago, but couldn't because of legacy toolchains. Here's hoping this is the final solution for those @#$%^ macros. Boris, thanks for looping Nick in, I should have done so to begin with. -- Josh