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=-10.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 43F43C4CEC6 for ; Thu, 12 Sep 2019 20:08:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1F51020830 for ; Thu, 12 Sep 2019 20:08:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726909AbfILUIn (ORCPT ); Thu, 12 Sep 2019 16:08:43 -0400 Received: from mga01.intel.com ([192.55.52.88]:35550 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727205AbfILUHy (ORCPT ); Thu, 12 Sep 2019 16:07:54 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Sep 2019 13:07:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,489,1559545200"; d="scan'208";a="336688223" Received: from chang-linux-3.sc.intel.com ([172.25.66.185]) by orsmga004.jf.intel.com with ESMTP; 12 Sep 2019 13:07:53 -0700 From: "Chang S. Bae" To: linux-kernel@vger.kernel.org Cc: ravi.v.shankar@intel.com, chang.seok.bae@intel.com, Andi Kleen , Andy Lutomirski , Thomas Gleixner , Borislav Petkov , Dave Hansen , Tony Luck , "H . Peter Anvin" Subject: [PATCH v8 04/17] x86/fsgsbase/64: Add intrinsics for FSGSBASE instructions Date: Thu, 12 Sep 2019 13:06:45 -0700 Message-Id: <1568318818-4091-5-git-send-email-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1568318818-4091-1-git-send-email-chang.seok.bae@intel.com> References: <1568318818-4091-1-git-send-email-chang.seok.bae@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen [ luto: Rename the variables from FS and GS to FSBASE and GSBASE and make safe to include on 32-bit kernels. ] Signed-off-by: Andi Kleen Signed-off-by: Andy Lutomirski Signed-off-by: Chang S. Bae Signed-off-by: Thomas Gleixner Reviewed-by: Andy Lutomirski Reviewed-by: Andi Kleen Reviewed-by: Tony Luck Cc: Thomas Gleixner Cc: Borislav Petkov Cc: Andy Lutomirski Cc: Dave Hansen Cc: Tony Luck Cc: H. Peter Anvin Cc: Andi Kleen --- Changes from v7: * No code change * Trimmed the changelog by Thomas --- arch/x86/include/asm/fsgsbase.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/arch/x86/include/asm/fsgsbase.h b/arch/x86/include/asm/fsgsbase.h index bca4c74..fdd1177 100644 --- a/arch/x86/include/asm/fsgsbase.h +++ b/arch/x86/include/asm/fsgsbase.h @@ -19,6 +19,36 @@ extern unsigned long x86_gsbase_read_task(struct task_struct *task); extern void x86_fsbase_write_task(struct task_struct *task, unsigned long fsbase); extern void x86_gsbase_write_task(struct task_struct *task, unsigned long gsbase); +/* Must be protected by X86_FEATURE_FSGSBASE check. */ + +static __always_inline unsigned long rdfsbase(void) +{ + unsigned long fsbase; + + asm volatile("rdfsbase %0" : "=r" (fsbase) :: "memory"); + + return fsbase; +} + +static __always_inline unsigned long rdgsbase(void) +{ + unsigned long gsbase; + + asm volatile("rdgsbase %0" : "=r" (gsbase) :: "memory"); + + return gsbase; +} + +static __always_inline void wrfsbase(unsigned long fsbase) +{ + asm volatile("wrfsbase %0" :: "r" (fsbase) : "memory"); +} + +static __always_inline void wrgsbase(unsigned long gsbase) +{ + asm volatile("wrgsbase %0" :: "r" (gsbase) : "memory"); +} + /* Helper functions for reading/writing FS/GS base */ static inline unsigned long x86_fsbase_read_cpu(void) -- 2.7.4