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 047F5C4646A for ; Wed, 12 Sep 2018 13:36:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC9DA20880 for ; Wed, 12 Sep 2018 13:36:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BC9DA20880 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 S1728172AbeILSlD (ORCPT ); Wed, 12 Sep 2018 14:41:03 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:43916 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728038AbeILSkf (ORCPT ); Wed, 12 Sep 2018 14:40:35 -0400 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1g05JF-0001Ap-Il; Wed, 12 Sep 2018 15:35:57 +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 08/10] x86/fpu: prepare copy_fpstate_to_sigframe for TIF_LOAD_FPU Date: Wed, 12 Sep 2018 15:33:51 +0200 Message-Id: <20180912133353.20595-9-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 If TIF_LOAD_FPU is set, then the registers are saved (not loaded). In that case we skip the saving part. Signed-off-by: Rik van Riel Signed-off-by: Sebastian Andrzej Siewior --- arch/x86/kernel/fpu/signal.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index ff6e7a67522d8..906efd9572ffa 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -155,13 +155,17 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size) sizeof(struct user_i387_ia32_struct), NULL, (struct _fpstate_32 __user *) buf) ? -1 : 1; - /* Update the thread's fxstate to save the fsave header. */ - if (ia32_fxstate) - copy_fxregs_to_kernel(fpu); - else { - copy_fpregs_to_fpstate(fpu); - fpregs_deactivate(fpu); + __fpregs_changes_begin(); + if (!test_thread_flag(TIF_LOAD_FPU)) { + /* Update the thread's fxstate to save the fsave header. */ + if (ia32_fxstate) + copy_fxregs_to_kernel(fpu); + else { + copy_fpregs_to_fpstate(fpu); + fpregs_deactivate(fpu); + } } + __fpregs_changes_end(); if (using_compacted_format()) { copy_xstate_to_user(buf_fx, xsave, 0, size); -- 2.19.0