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=-8.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 CA4D3C67839 for ; Wed, 12 Dec 2018 17:11:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9011B20851 for ; Wed, 12 Dec 2018 17:11:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="cZLpuX2o" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9011B20851 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=alien8.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 S1728041AbeLLRLk (ORCPT ); Wed, 12 Dec 2018 12:11:40 -0500 Received: from mail.skyhub.de ([5.9.137.197]:36192 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726922AbeLLRLj (ORCPT ); Wed, 12 Dec 2018 12:11:39 -0500 Received: from zn.tnic (p200300EC2BCDD800846D0A96F290A465.dip0.t-ipconnect.de [IPv6:2003:ec:2bcd:d800:846d:a96:f290:a465]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id BCB2F1EC0B39; Wed, 12 Dec 2018 18:11:37 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1544634697; 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:in-reply-to:in-reply-to: references:references; bh=KE0LWdpLqCLFWs9wAIeFXWVm4rPOl7dno2knwk2pHeQ=; b=cZLpuX2o1ile8KPlpyBmb8hKjAwpKO9kKeMbpxBf+PihmnyHSYtr8SzsRRvbq4uIwd5Br/ DSiiisq6RTehV5KlFnt4OUy0YJ4Rn13oDhx/eWzOzENsRW0xvIj7Iz48pVQIPtXePcye/Z vj/OvYCcb8khCywXVlgUdsam74x993k= Date: Wed, 12 Dec 2018 18:11:29 +0100 From: Borislav Petkov To: Sebastian Andrzej Siewior Cc: linux-kernel@vger.kernel.org, x86@kernel.org, Andy Lutomirski , Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , kvm@vger.kernel.org, "Jason A. Donenfeld" , Rik van Riel , Dave Hansen Subject: Re: [PATCH 11/29] x86/fpu: Always init the `state' in fpu__clear() Message-ID: <20181212171129.GD6653@zn.tnic> References: <20181128222035.2996-1-bigeasy@linutronix.de> <20181128222035.2996-12-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20181128222035.2996-12-bigeasy@linutronix.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 28, 2018 at 11:20:17PM +0100, Sebastian Andrzej Siewior wrote: > fpu__clear() only initializes the `state' if the FPU is present. This > initialisation is also required for the FPU-less system and takes place > math_emulate(). Since fpu__initialize() only performs the initialization > if ->initialized is zero it does not matter that it is invoked each time > an opcode is emulated. It makes the removal of ->initialized easier if > the struct is also initialized in FPU-less case at the same time. > > Move fpu__initialize() before the FPU check so it is also performed in > FPU-less case. > > Signed-off-by: Sebastian Andrzej Siewior > --- > arch/x86/include/asm/fpu/internal.h | 1 - > arch/x86/kernel/fpu/core.c | 5 ++--- > arch/x86/math-emu/fpu_entry.c | 3 --- > 3 files changed, 2 insertions(+), 7 deletions(-) ... > diff --git a/arch/x86/math-emu/fpu_entry.c b/arch/x86/math-emu/fpu_entry.c > index 9e2ba7e667f61..a873da6b46d6b 100644 > --- a/arch/x86/math-emu/fpu_entry.c > +++ b/arch/x86/math-emu/fpu_entry.c > @@ -113,9 +113,6 @@ void math_emulate(struct math_emu_info *info) > unsigned long code_base = 0; > unsigned long code_limit = 0; /* Initialized to stop compiler warnings */ > struct desc_struct code_descriptor; > - struct fpu *fpu = ¤t->thread.fpu; > - > - fpu__initialize(fpu); Ok, you're removing it here but where is the FPU going to be initialized now in the FPU-less case? IOW, it is not clear to me where fpu__clear() get called for the FPU emulation case now... -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.