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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 E7575C2B9F4 for ; Mon, 14 Jun 2021 16:39:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D57C5613CD for ; Mon, 14 Jun 2021 16:39:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235225AbhFNQmA (ORCPT ); Mon, 14 Jun 2021 12:42:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234007AbhFNQkg (ORCPT ); Mon, 14 Jun 2021 12:40:36 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A35CC061767 for ; Mon, 14 Jun 2021 09:38:33 -0700 (PDT) Message-Id: <20210614155357.567131213@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1623688712; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=8bNqn55/9FpzYwdYhLYJ1YHhSO8g4U3kMgFFLHLaBYo=; b=KgEFffgwBJqMOqSJ1ZSofsAEQjQGYxtI5t+Hy8QmmaEDya052DYa+ctwZ/mxpbckfLRm1v go+jy5nezpE1DeR435olXaDWXIxfCoDnPX/IB7ZFwwoyEqXy27Y8TrPF9nbzXbfLydj/L2 j17uM+IIom9NrO04BOJPRdyZSzEYiiV6K2ZwTy0wtMdBWRQDU522NFJM7TVqqSKRBHWh39 bPV18YASBhawiSfcSBQ3wBSCQNtUW9aTPyu/ptrUWv0397eA1kRWOBnCeKexQnZIzKfsIP pz5JJMgR2xQ3DqG8acaHUHtpTNwojRUWZezInf/wZIo8k8EHWiXsGhiq7VAGoQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1623688712; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=8bNqn55/9FpzYwdYhLYJ1YHhSO8g4U3kMgFFLHLaBYo=; b=yCR8VRtJBfr8hVfkr4tWkQNmO53PxAOX6WfeNU258+PnFXI8AeFTCAJ+aagvfNa2tGhP5u y19Q0Q8L7iswYICQ== Date: Mon, 14 Jun 2021 17:44:46 +0200 From: Thomas Gleixner To: LKML Cc: Andy Lutomirski , Dave Hansen , Fenghua Yu , Tony Luck , Yu-cheng Yu , Sebastian Andrzej Siewior , Borislav Petkov , Peter Zijlstra , Kan Liang Subject: [patch V2 38/52] x86/cpu: Write the default PKRU value when enabling PKE References: <20210614154408.673478623@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-transfer-encoding: 8-bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In preparation of making the PKRU management more independent from XSTATES, write the default PKRU value into the hardware right after enabling PKRU in CR4. This ensures that switch_to() and copy_thread() have the correct setting for init task and the per CPU idle threads right away. Signed-off-by: Thomas Gleixner --- arch/x86/kernel/cpu/common.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -480,6 +480,8 @@ static __always_inline void setup_pku(st } cr4_set_bits(X86_CR4_PKE); + /* Load the default PKRU value */ + pkru_write_default(); } #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS