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=1.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, FSL_HELO_FAKE,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 2B804C2BC61 for ; Mon, 29 Oct 2018 06:36:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D85682084A for ; Mon, 29 Oct 2018 06:36:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="pK7v24AY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D85682084A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729318AbeJ2PXr (ORCPT ); Mon, 29 Oct 2018 11:23:47 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:33474 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729225AbeJ2PXr (ORCPT ); Mon, 29 Oct 2018 11:23:47 -0400 Received: by mail-wm1-f66.google.com with SMTP id y140-v6so8746977wmd.0 for ; Sun, 28 Oct 2018 23:36:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=E6Sl1tmZWWW0AWdMle+xbaUVhojDJN54bGThAU0YBH8=; b=pK7v24AYQyvrCrbIcjPHS9oEFA5MthKeUDdOTFwOcThB7GX8hvPm6lNeC9cTjfcvOu coD5LNMeTQyhd8w5B6EvwwMY/uUiUVGF48Q4/2WnhuCO3Ybcbc5kI09IQlqvAmVNyKW2 PTmUWZmXNgQuvU+VosI0HH9RuD2eTZJKgmVDv+MigJRyJqjZgZb4835rvH8Nd0ep/Xbj jFISpJRW9ehhSYhhRzfk8S6wfEnZdcZGCk+mSey3RO2Yfp/i2Z9U7CwNE9n4fMHthyQf RHewi3BkWCf85iDY8e/amWmYXpwiJYtLnlbegQS3/lrGMoqRjFz8PqbGP9otp6Ox8YkW IDGQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=E6Sl1tmZWWW0AWdMle+xbaUVhojDJN54bGThAU0YBH8=; b=XaFmYKgiz4MuJ4IjlBIaedJo9rM0Bu/+WcV4yYqHdBL9gcZcHljja901CArurM1JFJ 9yaQKzePfvf5m7s5bRbPJmiSvMHl+G5Qx3lBWIum7tcUJJB6+6JNkZJIvgt1pnkEBTp+ m9rlAx/yH+8ZcKatLlvcYez5Ky58CVCb4YAWBXAJE2yW7C4m6wdA+M+zymxOQxJw/vB2 pAYuOpLxaCIzU0EukitdH9YFilTpwSZcUjw32r3CMezNV/zaJwvRI0tZicU0c+SV0LR/ JMO8t6c58jpch277NL2ZER373mYC6JTdEyOuRIOxcEdGr1VLkSg4EL1vOMlzNzsire0X bUiw== X-Gm-Message-State: AGRZ1gKp3KWLAapKEXAcY8/UEe0O+eWaeH/YFrrVY5sE7qLgMUevlOaH +eqHhoX3UEJ3Q+4mxvm6Sy8= X-Google-Smtp-Source: AJdET5fxhWMEDKZ27JmrGsExvY6zMcxPXxrBaAEmVEqyS2toCUpyQg9M/YyI0uhmR2bM5s8t/kkQ+A== X-Received: by 2002:a1c:27c5:: with SMTP id n188-v6mr8451020wmn.88.1540794989119; Sun, 28 Oct 2018 23:36:29 -0700 (PDT) Received: from gmail.com (2E8B0CD5.catv.pool.telekom.hu. [46.139.12.213]) by smtp.gmail.com with ESMTPSA id x8-v6sm50814106wrd.54.2018.10.28.23.36.27 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sun, 28 Oct 2018 23:36:28 -0700 (PDT) Date: Mon, 29 Oct 2018 07:36:26 +0100 From: Ingo Molnar To: Daniel Micay Cc: Andy Lutomirski , Dave Hansen , Dave Hansen , kernel list , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , X86 ML , Peter Zijlstra , Michael Ellerman , Will Deacon , Andy Lutomirski , jroedel@suse.de Subject: Re: [PATCH 1/2] x86/pkeys: copy pkey state at fork() Message-ID: <20181029063626.GD128403@gmail.com> References: <20181026195146.9C7C1136@viggo.jf.intel.com> <0e5fd8bc-0b18-ea88-ed95-ec81a44d0783@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Daniel Micay wrote: > > I suppose we could add a new flag for pkey_get() or something. > > That would work, since I can apply the workaround (disabling the > feature in child processes) if I get EINVAL. The flag wouldn't need to > do anything, just existing and being tied to this patch so I have a > way to detect that I can safely use MPK after fork. A new flag for the pkey_alloc() syscall, right? Thanks, Ingo