From nobody Sun Sep 7 12:20:26 2025 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 D8EB3CDB482 for ; Mon, 16 Oct 2023 16:32:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232557AbjJPQcu (ORCPT ); Mon, 16 Oct 2023 12:32:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232845AbjJPQcJ (ORCPT ); Mon, 16 Oct 2023 12:32:09 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 296C34499; Mon, 16 Oct 2023 09:19:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697473197; x=1729009197; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=rWXAJsBXvldwnJdPf0k5N9icvjGGM79jJW+iAC1XCxs=; b=K7A+CE39uH2sTwy5qJ/8M9Q1XAty2u4OhuKl7ZTlj+iVVSRNQs++MRaT gkZKod2Qmr3NrqOj58VWC0X1YPSJi4TGx7C2EUHiBWZzRBewnJIuh084b 5RJqpFn7CDt9r2uzw+KZ7Z5Rsvc15XRSgY1i5i8mzg3RsXBxo2OJZZbmf bABiubG/TjxnkxbOngyiEtZIGPTWiBJVl5J2Dig7sDGWrbr8bol254R5C BMFanGYxL57PDRJvrV5tkOw13mHynya+OOqiKB1gKL4SGWNlB6BEhczjU DUWt5Ytev3GCeloWA/TV4cf1palG6REYDbNwzMLEsXTjd1FYgUgwZDIeW Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="364921992" X-IronPort-AV: E=Sophos;i="6.03,229,1694761200"; d="scan'208";a="364921992" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 09:16:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10865"; a="846448264" X-IronPort-AV: E=Sophos;i="6.03,229,1694761200"; d="scan'208";a="846448264" Received: from ls.sc.intel.com (HELO localhost) ([172.25.112.31]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2023 09:16:00 -0700 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar , David Matlack , Kai Huang , Zhi Wang , chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com, Yao Yuan Subject: [PATCH v16 083/116] KVM: TDX: Handle vmentry failure for INTEL TD guest Date: Mon, 16 Oct 2023 09:14:35 -0700 Message-Id: X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Yao Yuan TDX module passes control back to VMM if it failed to vmentry for a TD, use same exit reason to notify user space, align with VMX. If VMM corrupted TD VMCS, machine check during entry can happens. vm exit reason will be EXIT_REASON_MCE_DURING_VMENTRY. If VMM corrupted TD VMCS with debug TD by TDH.VP.WR, the exit reason would be EXIT_REASON_INVALID_STATE or EXIT_REASON_MSR_LOAD_FAIL. Signed-off-by: Yao Yuan --- arch/x86/kvm/vmx/tdx.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index be73b8322a66..306d555dda35 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1314,6 +1314,28 @@ int tdx_handle_exit(struct kvm_vcpu *vcpu, fastpath_= t fastpath) goto unhandled_exit; } =20 + /* + * When TDX module saw VMEXIT_REASON_FAILED_VMENTER_MC etc, TDH.VP.ENTER + * returns with TDX_SUCCESS | exit_reason with failed_vmentry =3D 1. + * Because TDX module maintains TD VMCS correctness, usually vmentry + * failure shouldn't happen. In some corner cases it can happen. For + * example + * - machine check during entry: EXIT_REASON_MCE_DURING_VMENTRY + * - TDH.VP.WR with debug TD. VMM can corrupt TD VMCS + * - EXIT_REASON_INVALID_STATE + * - EXIT_REASON_MSR_LOAD_FAIL + */ + if (unlikely(exit_reason.failed_vmentry)) { + pr_err("TDExit: exit_reason 0x%016llx qualification=3D%016lx ext_qualifi= cation=3D%016lx\n", + exit_reason.full, tdexit_exit_qual(vcpu), tdexit_ext_exit_qual(vc= pu)); + vcpu->run->exit_reason =3D KVM_EXIT_FAIL_ENTRY; + vcpu->run->fail_entry.hardware_entry_failure_reason + =3D exit_reason.full; + vcpu->run->fail_entry.cpu =3D vcpu->arch.last_vmentry_cpu; + + return 0; + } + WARN_ON_ONCE(fastpath !=3D EXIT_FASTPATH_NONE); =20 switch (exit_reason.basic) { --=20 2.25.1