From patchwork Tue Feb 16 02:13:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Isaku Yamahata X-Patchwork-Id: 12089467 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 27489C433E0 for ; Tue, 16 Feb 2021 02:22:57 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A58BC64D9D for ; Tue, 16 Feb 2021 02:22:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A58BC64D9D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49680 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lBq0t-0006Va-OC for qemu-devel@archiver.kernel.org; Mon, 15 Feb 2021 21:22:55 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:45996) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lBptH-00064k-HG for qemu-devel@nongnu.org; Mon, 15 Feb 2021 21:15:03 -0500 Received: from mga17.intel.com ([192.55.52.151]:25639) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lBptF-0001Zp-Ng for qemu-devel@nongnu.org; Mon, 15 Feb 2021 21:15:03 -0500 IronPort-SDR: uD+2snnvicz/6NY9AzisANtIIdcNuTS7rDoGMfXqKjdoGQ/HO1toR3ez3H3mepQOOVRIkMgU4H Qb5h3m5jvUNQ== X-IronPort-AV: E=McAfee;i="6000,8403,9896"; a="162558760" X-IronPort-AV: E=Sophos;i="5.81,182,1610438400"; d="scan'208";a="162558760" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Feb 2021 18:14:51 -0800 IronPort-SDR: IMUUA3bKKiJ20NH1cCwy4eaJvgH448mUZ64kz7iauktw/bpJCLxiti5q80tCZBoM3DZVVp7iKB 9PWCJJoT1mrg== X-IronPort-AV: E=Sophos;i="5.81,182,1610438400"; d="scan'208";a="591705407" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Feb 2021 18:14:51 -0800 From: Isaku Yamahata To: qemu-devel@nongnu.org, pbonzini@redhat.com, alistair@alistair23.me, ehabkost@redhat.com, marcel.apfelbaum@gmail.com, mst@redhat.com, cohuck@redhat.com, mtosatti@redhat.com, xiaoyao.li@intel.com, seanjc@google.com Subject: [RFC PATCH 09/23] target/i386: kvm: don't synchronize guest tsc for TD guest Date: Mon, 15 Feb 2021 18:13:05 -0800 Message-Id: X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: Received-SPF: pass client-ip=192.55.52.151; envelope-from=isaku.yamahata@intel.com; helo=mga17.intel.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, kvm@vger.kernel.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Make kvm_synchronize_all_tsc() nop for TD-guest. TDX module specification, 9.11.1 TSC Virtualization "Virtual TSC values are consistent among all the TD;s VCPUs at the level suppored by the CPU". There is no need for qemu to synchronize tsc and VMM can't access to guest TSC. Actually do_kvm_synchronize_tsc() hits assert due to failure to write to guest tsc. > qemu/target/i386/kvm.c:235: kvm_get_tsc: Assertion `ret == 1' failed. Signed-off-by: Isaku Yamahata --- target/i386/kvm/kvm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index fb94cdd370..beb768a7d3 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -247,7 +247,7 @@ void kvm_synchronize_all_tsc(void) { CPUState *cpu; - if (kvm_enabled()) { + if (kvm_enabled() && vm_type != KVM_X86_TDX_VM) { CPU_FOREACH(cpu) { run_on_cpu(cpu, do_kvm_synchronize_tsc, RUN_ON_CPU_NULL); }