From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751393AbeFDTYy (ORCPT ); Mon, 4 Jun 2018 15:24:54 -0400 Received: from mga05.intel.com ([192.55.52.43]:40504 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751164AbeFDTYq (ORCPT ); Mon, 4 Jun 2018 15:24:46 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,476,1520924400"; d="scan'208";a="64240688" From: "Chang S. Bae" To: Andy Lutomirski , "H . Peter Anvin" , Thomas Gleixner , Ingo Molnar Cc: Andi Kleen , Dave Hansen , Markus T Metzger , "Ravi V . Shankar" , "Chang S . Bae" , LKML Subject: [PATCH 4/6] x86/fsgsbase/64: Factor out load FS/GS segments from __switch_to Date: Mon, 4 Jun 2018 12:24:27 -0700 Message-Id: <1528140269-26205-5-git-send-email-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1528140269-26205-1-git-send-email-chang.seok.bae@intel.com> References: <1528140269-26205-1-git-send-email-chang.seok.bae@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Instead of open code, load_fsgs() will cleanup __switch_to and symmetric with FS/GS segment save. When FSGSBASE enabled, X86_FEATURE_FSGSBASE check will be incorporated. Signed-off-by: Chang S. Bae Reviewed-by: Andi Kleen Cc: Andy Lutomirski Cc: H. Peter Anvin Cc: Dave Hansen Cc: Thomas Gleixner Cc: Ingo Molnar Reviewed-by: Andy Lutomirski --- arch/x86/kernel/process_64.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index e498671..cebf240 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -279,6 +279,15 @@ static __always_inline void load_seg_legacy(unsigned short prev_index, } } +static __always_inline void load_fsgs(struct thread_struct *prev, + struct thread_struct *next) +{ + load_seg_legacy(prev->fsindex, prev->fsbase, + next->fsindex, next->fsbase, FS); + load_seg_legacy(prev->gsindex, prev->gsbase, + next->gsindex, next->gsbase, GS); +} + static unsigned long task_seg_base(struct task_struct *task, unsigned short selector) { @@ -588,10 +597,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) if (unlikely(next->ds | prev->ds)) loadsegment(ds, next->ds); - load_seg_legacy(prev->fsindex, prev->fsbase, - next->fsindex, next->fsbase, FS); - load_seg_legacy(prev->gsindex, prev->gsbase, - next->gsindex, next->gsbase, GS); + load_fsgs(prev, next); switch_fpu_finish(next_fpu, cpu); -- 2.7.4