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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A3C1DC46469 for ; Wed, 12 Sep 2018 13:36:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 67C9F20880 for ; Wed, 12 Sep 2018 13:36:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 67C9F20880 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de 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 S1728198AbeILSlP (ORCPT ); Wed, 12 Sep 2018 14:41:15 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:43898 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727752AbeILSkc (ORCPT ); Wed, 12 Sep 2018 14:40:32 -0400 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1g05JD-0001Ap-EW; Wed, 12 Sep 2018 15:35:55 +0200 From: Sebastian Andrzej Siewior To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, Andy Lutomirski , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , kvm@vger.kernel.org, "Jason A. Donenfeld" , Rik van Riel , Sebastian Andrzej Siewior Subject: [RFC PATCH 05/10] x86/pkeys: Drop the preempt-disable section Date: Wed, 12 Sep 2018 15:33:48 +0200 Message-Id: <20180912133353.20595-6-bigeasy@linutronix.de> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20180912133353.20595-1-bigeasy@linutronix.de> References: <20180912133353.20595-1-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rik van Riel The fpu->initialized flag should not be changed underneath us. This might be a fallout during the removal of the LazyFPU support. The FPU is marked initialized as soon as the state has been set to an initial value. It does not signal if the CPU's FPU registers are loaded. Signed-off-by: Rik van Riel Signed-off-by: Sebastian Andrzej Siewior --- arch/x86/mm/pkeys.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index c7a7b6bd64009..6e91529fe2a30 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -53,17 +53,13 @@ int __execute_only_pkey(struct mm_struct *mm) * dance to set PKRU if we do not need to. Check it * first and assume that if the execute-only pkey is * write-disabled that we do not have to set it - * ourselves. We need preempt off so that nobody - * can make fpregs inactive. + * ourselves. */ - preempt_disable(); if (!need_to_set_mm_pkey && current->thread.fpu.initialized && !__pkru_allows_read(read_pkru(), execute_only_pkey)) { - preempt_enable(); return execute_only_pkey; } - preempt_enable(); /* * Set up PKRU so that it denies access for everything -- 2.19.0