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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 87F80C433DF for ; Tue, 26 May 2020 16:15:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54ACE206D5 for ; Tue, 26 May 2020 16:15:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="YNNvSaAN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728294AbgEZQPH (ORCPT ); Tue, 26 May 2020 12:15:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727941AbgEZQPH (ORCPT ); Tue, 26 May 2020 12:15:07 -0400 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45A6FC03E96D for ; Tue, 26 May 2020 09:15:07 -0700 (PDT) Received: by mail-pl1-x643.google.com with SMTP id x11so7877288plv.9 for ; Tue, 26 May 2020 09:15:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=IdTmx5bvE+V1cAcFJI98GnDSoP0mb5MfVH5Axb1TejM=; b=YNNvSaANvznznsq6NwzIsZWeDzc27QMCyU/RLQFt132rryBivrtEuaFvxLjynP9vOC lrwK6MQNyNlvBZmT/WVxhaRyPcDs+pAsTRKf58LrEcBxV4nseo6f1t3PdSvmHFV4uf0H g1OP43Bipju2hrlrFmsJXumIB96rviCx8CjEg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=IdTmx5bvE+V1cAcFJI98GnDSoP0mb5MfVH5Axb1TejM=; b=tZr9M4EMRXrK0mXiEjKSwhMdL/SZxK6aKam8udIBZZHsIdACng4nTHyXV06ywZ+6yj cclTkWUtsg0e/x89lUoWftBApd/IDunAIjb6xtmdCE1jZyQwrouDBD0Ec03i3LxjULwP fT8nPI0csmHqejjrMVDVjS5fmVwBfnX/sLXQwJz+goCm58+qGS34/pplwaMb97JeeNX/ l/uud1eD/VZHwcp6jtiFXxulcdLEcvfr0V24RJhwsYj3QVQcVukM8M471V4PgQ/assVL 2zckh0sFkFaAytNbj6S8Jy4cZBh/YmukdUW48Kz833zLbtOpiBpQ2wEwDokiL/3trqNc z2RA== X-Gm-Message-State: AOAM532BLr2X7m6MXI+0VEeUR7/JoC9w9HD1DFscqas1CFYBirwW63pJ QQUcIduvOcWjCi3ff5by6e8dGA== X-Google-Smtp-Source: ABdhPJzdYWXboruOLBkXnWjJPQ/weKAztCxQPCSyM3XiKpaGg2ZHsjoGl/AuQAdP804jyn88zCCNbg== X-Received: by 2002:a17:90a:2a8e:: with SMTP id j14mr21920pjd.136.1590509706847; Tue, 26 May 2020 09:15:06 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id g18sm33078pfq.146.2020.05.26.09.15.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 26 May 2020 09:15:06 -0700 (PDT) Date: Tue, 26 May 2020 09:15:04 -0700 From: Kees Cook To: Greg KH Cc: Andi Kleen , x86@kernel.org, linux-kernel@vger.kernel.org, sashal@kernel.org, Andi Kleen , stable@vger.kernel.org Subject: Re: [PATCH v1] x86: Pin cr4 FSGSBASE Message-ID: <202005260912.8867B3AA@keescook> References: <20200526052848.605423-1-andi@firstfloor.org> <20200526065618.GC2580410@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200526065618.GC2580410@kroah.com> Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Tue, May 26, 2020 at 08:56:18AM +0200, Greg KH wrote: > What about those systems that panic-on-warn? This is (modulo the general discussion about whether it's the right way to check) the correct use for WARN*(). It's an undesirable system state; people choosing panic-on-warn want this: https://www.kernel.org/doc/html/latest/process/deprecated.html#bug-and-bug-on -- Kees Cook