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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 6C9FFC282DD for ; Thu, 9 Jan 2020 21:17:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3735D2073A for ; Thu, 9 Jan 2020 21:17:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728391AbgAIVRA (ORCPT ); Thu, 9 Jan 2020 16:17:00 -0500 Received: from mga09.intel.com ([134.134.136.24]:44432 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725775AbgAIVQ7 (ORCPT ); Thu, 9 Jan 2020 16:16:59 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Jan 2020 13:16:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,414,1571727600"; d="scan'208";a="212025752" Received: from yyu32-desk.sc.intel.com ([143.183.136.51]) by orsmga007.jf.intel.com with ESMTP; 09 Jan 2020 13:16:58 -0800 From: Yu-cheng Yu To: linux-kernel@vger.kernel.org, x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , Dave Hansen , Tony Luck , Andy Lutomirski , Borislav Petkov , Rik van Riel , "Ravi V. Shankar" , Sebastian Andrzej Siewior , Fenghua Yu , Peter Zijlstra Cc: Yu-cheng Yu Subject: [PATCH 1/3] x86/fpu/xstate: Fix last_good_offset in setup_xstate_features() Date: Thu, 9 Jan 2020 13:14:50 -0800 Message-Id: <20200109211452.27369-2-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200109211452.27369-1-yu-cheng.yu@intel.com> References: <20200109211452.27369-1-yu-cheng.yu@intel.com> 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 The function setup_xstate_features() uses CPUID to find each xfeature's standard-format offset and size. Since XSAVES always uses the compacted format, supervisor xstates are *NEVER* in the standard-format and their offsets are left as -1's. However, they are still being tracked as last_good_offset. Fix it by tracking only user xstate offsets. Signed-off-by: Yu-cheng Yu Reviewed-by: Dave Hansen --- arch/x86/kernel/fpu/xstate.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index a1806598aaa4..3ef3603bcfc5 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -265,22 +265,26 @@ static void __init setup_xstate_features(void) cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx); + xstate_sizes[i] = eax; + /* * If an xfeature is supervisor state, the offset * in EBX is invalid. We leave it to -1. */ - if (xfeature_is_user(i)) + if (xfeature_is_user(i)) { xstate_offsets[i] = ebx; - xstate_sizes[i] = eax; - /* - * In our xstate size checks, we assume that the - * highest-numbered xstate feature has the - * highest offset in the buffer. Ensure it does. - */ - WARN_ONCE(last_good_offset > xstate_offsets[i], - "x86/fpu: misordered xstate at %d\n", last_good_offset); - last_good_offset = xstate_offsets[i]; + /* + * In our xstate size checks, we assume that the + * highest-numbered xstate feature has the + * highest offset in the buffer. Ensure it does. + */ + WARN_ONCE(last_good_offset > xstate_offsets[i], + "x86/fpu: misordered xstate at %d\n", + last_good_offset); + + last_good_offset = xstate_offsets[i]; + } } } -- 2.21.0