From patchwork Thu Feb 25 11:38:51 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Vrabel X-Patchwork-Id: 8423031 Return-Path: X-Original-To: patchwork-xen-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 7D188C0553 for ; Thu, 25 Feb 2016 11:41:09 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9C8BD202E6 for ; Thu, 25 Feb 2016 11:41:08 +0000 (UTC) Received: from lists.xen.org (unknown [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E2E4120265 for ; Thu, 25 Feb 2016 11:41:07 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xen.org) by lists.xen.org with esmtp (Exim 4.84) (envelope-from ) id 1aYuG1-0001TK-Jd; Thu, 25 Feb 2016 11:38:57 +0000 Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.84) (envelope-from ) id 1aYuFz-0001T6-Sj for xen-devel@lists.xenproject.org; Thu, 25 Feb 2016 11:38:55 +0000 Received: from [85.158.139.211] by server-7.bemta-5.messagelabs.com id EC/6B-03511-FC7EEC65; Thu, 25 Feb 2016 11:38:55 +0000 X-Env-Sender: prvs=85605cf9d=david.vrabel@citrix.com X-Msg-Ref: server-7.tower-206.messagelabs.com!1456400333!24698183!1 X-Originating-IP: [66.165.176.63] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogNjYuMTY1LjE3Ni42MyA9PiAzMDYwNDg=\n, received_headers: No Received headers X-StarScan-Received: X-StarScan-Version: 7.35.1; banners=-,-,- X-VirusChecked: Checked Received: (qmail 50032 invoked from network); 25 Feb 2016 11:38:54 -0000 Received: from smtp02.citrix.com (HELO SMTP02.CITRIX.COM) (66.165.176.63) by server-7.tower-206.messagelabs.com with RC4-SHA encrypted SMTP; 25 Feb 2016 11:38:54 -0000 X-IronPort-AV: E=Sophos;i="5.22,498,1449532800"; d="scan'208";a="341034644" To: Jan Beulich References: <1456397884-661-1-git-send-email-david.vrabel@citrix.com> <1456397884-661-3-git-send-email-david.vrabel@citrix.com> <56CEF27402000078000D61A2@prv-mh.provo.novell.com> From: David Vrabel X-Enigmail-Draft-Status: N1110 Message-ID: <56CEE7CB.3040407@citrix.com> Date: Thu, 25 Feb 2016 11:38:51 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.5.0 MIME-Version: 1.0 In-Reply-To: <56CEF27402000078000D61A2@prv-mh.provo.novell.com> X-DLP: MIA1 Cc: Andrew Cooper , xen-devel@lists.xenproject.org Subject: Re: [Xen-devel] [PATCHv3 2/3] x86/fpu: Add a per-domain field to set the width of FIP/FDP X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Spam-Status: No, score=-1.1 required=5.0 tests=BAYES_00,RDNS_NONE, UNPARSEABLE_RELAY autolearn=no version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 25/02/16 11:24, Jan Beulich wrote: >>>> On 25.02.16 at 11:58, wrote: >> @@ -261,7 +261,15 @@ void xsave(struct vcpu *v, uint64_t mask) >> "=m" (*ptr), \ >> "a" (lmask), "d" (hmask), "D" (ptr)) >> >> - if ( word_size <= 0 || !is_pv_32bit_vcpu(v) ) >> + if ( fip_width == 8 ) >> + { >> + XSAVE("0x48,"); >> + } >> + else if ( fip_width == 4 ) >> + { >> + XSAVE(""); >> + } >> + else > > Both conditions would now better also check mask & XSTATE_FP, > since going these routes (and namely bypassing the FIP check, as > was done before) is fine when FP state is not being saved. Is this what you mean? David --- a/xen/arch/x86/xstate.c +++ b/xen/arch/x86/xstate.c @@ -261,7 +261,7 @@ void xsave(struct vcpu *v, uint64_t mask) "=m" (*ptr), \ "a" (lmask), "d" (hmask), "D" (ptr)) - if ( fip_width == 8 ) + if ( fip_width == 8 || !(mask & XSTATE_FP) ) { XSAVE("0x48,"); }