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[139.178.88.99]) by mx.google.com with ESMTPS id pt17-20020a17090b3d1100b0029ac3f1fc24si149747pjb.37.2024.02.27.15.02.28 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Feb 2024 15:02:29 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-84156-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99; Authentication-Results: mx.google.com; arc=pass (i=1 spf=pass spfdomain=nefkom.net); spf=pass (google.com: domain of linux-kernel+bounces-84156-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) smtp.mailfrom="linux-kernel+bounces-84156-linux.lists.archive=gmail.com@vger.kernel.org" Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sv.mirrors.kernel.org (Postfix) with ESMTPS id D11D428EBE7 for ; Tue, 27 Feb 2024 23:02:28 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 663FB55E45; Tue, 27 Feb 2024 23:02:22 +0000 (UTC) Received: from mail-out.m-online.net (mail-out.m-online.net [212.18.0.9]) (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 37F0A1E86C; Tue, 27 Feb 2024 23:02:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.18.0.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709074941; cv=none; b=TgpjoD7vpfqrGIzE7snW8vBdM+AzFDgnc7gsyeh+kA5QEy1JDIcn4WmscghUSLGMNogHo1jQmOC9/oqlEjFywDjQaaoDppHwSt0aYhCSpt71BMhKDfbllseXi8v41XjF5QAVdEO63npNA/45dVMBUwJixTog3oZsf2IFJqhKatM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709074941; c=relaxed/simple; bh=S49evQSkI7rIhtVTwtSlf93JIi9GPebbgKntcqdpleU=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=j+6qRqAz38EIOqCWXgrHnEbtKRxjCzuXO/4Yu8ypUxVHRoHKGkjy28B7yHhEOVZrpn6CzXMjJ0w9zs8jjOdHE8hcR8/3QFBol9SDIIsrUDry23ng6QVWNZlm/jjvKK/fTiexGXrwKrn5x5W+LGF7tEtfeqzagjI9tXSBZK9Bnos= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org; spf=pass smtp.mailfrom=nefkom.net; arc=none smtp.client-ip=212.18.0.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nefkom.net Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4TktBw1pGYz1qsPL; Tue, 27 Feb 2024 23:56:24 +0100 (CET) Received: from localhost (dynscan1.mnet-online.de [192.168.6.68]) by mail.m-online.net (Postfix) with ESMTP id 4TktBw0r48z1qqlY; Tue, 27 Feb 2024 23:56:24 +0100 (CET) X-Virus-Scanned: amavis at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.68]) (amavis, port 10024) with ESMTP id rI9AB2bmZDcy; Tue, 27 Feb 2024 23:56:23 +0100 (CET) X-Auth-Info: Tx5lBDEGMLRTUQyblCbuJ3bg9NFXYwmbhPEjTzRsWqwGSw/+vO1HE4cryHgGnaif Received: from igel.home (aftr-62-216-202-59.dynamic.mnet-online.de [62.216.202.59]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Tue, 27 Feb 2024 23:56:23 +0100 (CET) Received: by igel.home (Postfix, from userid 1000) id 2E0572C1A60; Tue, 27 Feb 2024 23:56:23 +0100 (CET) From: Andreas Schwab To: Kees Cook Cc: Geert Uytterhoeven , Guenter Roeck , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] lib: stackinit: Adjust target string to 8 bytes for m68k In-Reply-To: <20240227224653.work.603-kees@kernel.org> (Kees Cook's message of "Tue, 27 Feb 2024 14:46:56 -0800") References: <20240227224653.work.603-kees@kernel.org> X-Yow: Yow! Are we in the perfect mood? Date: Tue, 27 Feb 2024 23:56:23 +0100 Message-ID: <87ttltzfc8.fsf@igel.home> User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Feb 27 2024, Kees Cook wrote: > For reasons I cannot understand, m68k moves the start of the stack frame > for consecutive calls to the same function It's called optimisation. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."