From patchwork Wed Jan 5 12:35:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Zhong X-Patchwork-Id: 12704294 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9078CC433EF for ; Wed, 5 Jan 2022 12:37:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240515AbiAEMhP (ORCPT ); Wed, 5 Jan 2022 07:37:15 -0500 Received: from mga04.intel.com ([192.55.52.120]:6468 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236627AbiAEMgG (ORCPT ); Wed, 5 Jan 2022 07:36:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1641386166; x=1672922166; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=39AEWRvAnr9fz29ORbLLCFWAQXfOaR2delgOiPJYM1I=; b=BkVbl9n3iAhi+EeD4SFV1kv+uPDrV/5q2czEQ7cJq49S7MjNplbNbJDR Y56AK9t/QKQ2hKNeJ1Ozqs13N420KmLvPfiPmjojU4fSXq9N1DVio48UL cnPDH+WIMo2cGelm6ze1IHdab72KWIRSH5KcTbFSW5kuEqZc0sX27iyNq V3f1527ExfSwFOt2LWrMAuRtX9QQpSrd+H2jxTUZDnWmmzq1w3pO0QoqX yfIVVdC5Wri/G99YkvqHBy154Kx3sjr1rS6c246QzoFUXrKz2jj/Oj70o LaA9QgORVavk1QBvi435pfvyU7qmmvYFyDtkreuZweGUNl5XijxjxJoA3 Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10217"; a="241249357" X-IronPort-AV: E=Sophos;i="5.88,263,1635231600"; d="scan'208";a="241249357" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jan 2022 04:35:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,263,1635231600"; d="scan'208";a="591004814" Received: from 984fee00bf64.jf.intel.com ([10.165.54.77]) by fmsmga004.fm.intel.com with ESMTP; 05 Jan 2022 04:35:33 -0800 From: Yang Zhong To: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, pbonzini@redhat.com, corbet@lwn.net, shuah@kernel.org, seanjc@google.com Cc: jun.nakajima@intel.com, kevin.tian@intel.com, jing2.liu@linux.intel.com, jing2.liu@intel.com, guang.zeng@intel.com, wei.w.wang@intel.com, yang.zhong@intel.com Subject: [PATCH v5 03/21] kvm: x86: Fix xstate_required_size() to follow XSTATE alignment rule Date: Wed, 5 Jan 2022 04:35:14 -0800 Message-Id: <20220105123532.12586-4-yang.zhong@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220105123532.12586-1-yang.zhong@intel.com> References: <20220105123532.12586-1-yang.zhong@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Jing Liu CPUID.0xD.1.EBX enumerates the size of the XSAVE area (in compacted format) required by XSAVES. If CPUID.0xD.i.ECX[1] is set for a state component (i), this state component should be located on the next 64-bytes boundary following the preceding state component in the compacted layout. Fix xstate_required_size() to follow the alignment rule. AMX is the first state component with 64-bytes alignment to catch this bug. Signed-off-by: Jing Liu Signed-off-by: Yang Zhong --- arch/x86/kvm/cpuid.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 0b920e12bb6d..f3e6fda6b858 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -42,7 +42,11 @@ static u32 xstate_required_size(u64 xstate_bv, bool compacted) if (xstate_bv & 0x1) { u32 eax, ebx, ecx, edx, offset; cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx); - offset = compacted ? ret : ebx; + /* ECX[1]: 64B alignment in compacted form */ + if (compacted) + offset = (ecx & 0x2) ? ALIGN(ret, 64) : ret; + else + offset = ebx; ret = max(ret, offset + eax); }