From patchwork Fri Dec 17 15:29:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jing Liu X-Patchwork-Id: 12685115 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 99405C433F5 for ; Fri, 17 Dec 2021 15:30:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238322AbhLQPaO (ORCPT ); Fri, 17 Dec 2021 10:30:14 -0500 Received: from mga03.intel.com ([134.134.136.65]:10852 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238196AbhLQPaI (ORCPT ); Fri, 17 Dec 2021 10:30:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1639755008; x=1671291008; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=YW4AxwndnvUQjvMrZxczR1u/34DqMkxUNjj5YnnNfFo=; b=SpobS4rjzrvoeH08FbfXnL4Y8OGrHttJdAv7lyH8ZcoyOCL6+78PY+m2 iVmUvR8SphGQeIhc09RA7CVfcqXblcNrfFtoBQQvI3pBwEDqXL6oE75sl gL1EMQBVLnjopTuuAZLZs38y2e4rOuVC0kVH8YWqWIwi+kjTpS+2HDm7E mye+yttn2AxTsPhAmA0NnOBi8JrZ7EV6Keg9tQ0XkXpSkZa18sHG2Kq+5 xKfZ0mCSHFoLEMNU0xnX8oPJfx+MQNfNGL20emkEfkGlh5LwH6Gq0QWGW Ip0nwbfuhN8/tHktCzxJl1om9sSCz0preYAsmAwMV90sf9zkNWHHn1e1/ w==; X-IronPort-AV: E=McAfee;i="6200,9189,10200"; a="239723460" X-IronPort-AV: E=Sophos;i="5.88,213,1635231600"; d="scan'208";a="239723460" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Dec 2021 07:30:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,213,1635231600"; d="scan'208";a="615588447" Received: from 984fee00a228.jf.intel.com ([10.165.56.59]) by orsmga004.jf.intel.com with ESMTP; 17 Dec 2021 07:30:05 -0800 From: Jing Liu To: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, pbonzini@redhat.com Cc: seanjc@google.com, 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 v2 15/23] kvm: x86: Add XCR0 support for Intel AMX Date: Fri, 17 Dec 2021 07:29:55 -0800 Message-Id: <20211217153003.1719189-16-jing2.liu@intel.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20211217153003.1719189-1-jing2.liu@intel.com> References: <20211217153003.1719189-1-jing2.liu@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Two XCR0 bits are defined for AMX to support XSAVE mechanism. Bit 17 is for tilecfg and bit 18 is for tiledata. The value of XCR0[17:18] is always either 00b or 11b. Also, SDM recommends that only 64-bit operating systems enable Intel AMX by setting XCR0[18:17]. If a 32-bit guest tries to set dynamic bits, it fails to pass vcpu->arch.guest_supported_xcr0 check and gets a #GP. Signed-off-by: Yang Zhong Signed-off-by: Jing Liu --- arch/x86/kvm/x86.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 15b093c58b3d..f8bacf18e6ed 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -210,7 +210,7 @@ static struct kvm_user_return_msrs __percpu *user_return_msrs; #define KVM_SUPPORTED_XCR0 (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \ | XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \ | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ - | XFEATURE_MASK_PKRU) + | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE) u64 __read_mostly host_efer; EXPORT_SYMBOL_GPL(host_efer); @@ -989,6 +989,12 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) if ((xcr0 & XFEATURE_MASK_AVX512) != XFEATURE_MASK_AVX512) return 1; } + +#ifdef CONFIG_X86_64 + if ((xcr0 & XFEATURE_MASK_XTILE) && + ((xcr0 & XFEATURE_MASK_XTILE) != XFEATURE_MASK_XTILE)) + return 1; +#endif vcpu->arch.xcr0 = xcr0; if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND)