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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 AA676C4743F for ; Tue, 8 Jun 2021 16:07:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92F8B6120F for ; Tue, 8 Jun 2021 16:07:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233809AbhFHQJd (ORCPT ); Tue, 8 Jun 2021 12:09:33 -0400 Received: from mga17.intel.com ([192.55.52.151]:57605 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232798AbhFHQIk (ORCPT ); Tue, 8 Jun 2021 12:08:40 -0400 IronPort-SDR: ef2tUwRpaXZ4yBKq6QE5S1yuMMS5NGiAuCeCC+RsoZedl1swafkY6q73a4bT8g7mCDFvRxJLhX 7+Ma/vMUk5jQ== X-IronPort-AV: E=McAfee;i="6200,9189,10009"; a="185249925" X-IronPort-AV: E=Sophos;i="5.83,258,1616482800"; d="scan'208";a="185249925" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jun 2021 09:06:47 -0700 IronPort-SDR: ejlF24rmLC3FQ4+zAV5ifYEShFLyGBkaVimSIpQAJhK2oKWh32GfEUgkiChqJPvkOdJq9JvQgx x8kv4Ubn+Hvw== X-IronPort-AV: E=Sophos;i="5.83,258,1616482800"; d="scan'208";a="637686229" Received: from ciball-mobl1.amr.corp.intel.com (HELO [10.252.140.48]) ([10.252.140.48]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Jun 2021 09:06:46 -0700 Subject: Re: [patch V3 4/6] x86/pkru: Make PKRU=0 actually work To: Thomas Gleixner , LKML Cc: x86@kernel.org, Andy Lutomirski , Dave Hansen , Fenghua Yu , Tony Luck , Yu-cheng Yu , Sebastian Andrzej Siewior , Rik van Riel , Borislav Petkov References: <20210608143617.565868844@linutronix.de> <20210608144346.045616965@linutronix.de> From: Dave Hansen Autocrypt: addr=dave.hansen@intel.com; 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210608144346.045616965@linutronix.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/8/21 7:36 AM, Thomas Gleixner wrote: > When user space brings PKRU into init state, then the kernel handling is > broken: Nit: while setting PKRU=0 _can_ trigger this issue (on AMD), the underlying problem is truly with the init state and not simply with any wrpkru(0). IOW, I like the changelog better than the subject. Maybe something like this would be more precise: x86/pkru: Write hardware init value to PKRU when xstate is init