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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 691B3D1268C for ; Tue, 5 Nov 2024 11:26:19 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1t8Hh3-0003NT-5H; Tue, 05 Nov 2024 06:25:53 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1t8Hgy-00033p-ON for qemu-devel@nongnu.org; Tue, 05 Nov 2024 06:25:50 -0500 Received: from mgamail.intel.com ([198.175.65.21]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1t8Hgl-0007vZ-04 for qemu-devel@nongnu.org; Tue, 05 Nov 2024 06:25:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1730805935; x=1762341935; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=s1wswE6/InO1G4xUqdts8qxxRWQM31X334rkUkdhdgU=; b=IHqnDDScRkhwTCeeT0sr/2SqXJTtMR9hRd4JPIDsB/4GNj9NJC5m/LLt 9PXInqrtphBj8yskQMgPQcBYLFRKz5BElmswicdDBltSTgtctVsZLzAhC YeMDowkuX6gc3jQzN1N6RtDVQ5DklNApLUCfIZnoLgBMOlrd/CFcCqAdx lrWqayGDfjRZ68QRRuwT+Ie5sf03QYar1dOnOXgiXKa062bq6cdPH0lgZ XEg20qqvlOZZKJbbLXdB74TBZ++27+pMhb9NgIUg5U6IZQ0Pg/NZU7MWI nZWqur0N9cTNSGKqKTlKZhtphxfqV3nYHwdFZnKcqjF67yBvDaE7dOLeu A==; X-CSE-ConnectionGUID: 95VwWKIUQdmRvCy9MzP8YQ== X-CSE-MsgGUID: ONw8q8yBSvWSt3kW95e2pA== X-IronPort-AV: E=McAfee;i="6700,10204,11222"; a="30503044" X-IronPort-AV: E=Sophos;i="6.11,199,1725346800"; d="scan'208";a="30503044" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2024 03:25:23 -0800 X-CSE-ConnectionGUID: DKTS63VqThuubrGE6o9gdg== X-CSE-MsgGUID: vLe/cltnQ9e0hJSfCrxoqQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,260,1725346800"; d="scan'208";a="84092452" Received: from xiaoyaol-hp-g830.ccr.corp.intel.com (HELO [10.124.247.1]) ([10.124.247.1]) by orviesa006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2024 03:25:20 -0800 Message-ID: Date: Tue, 5 Nov 2024 19:25:15 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 45/60] i386/tdx: Don't get/put guest state for TDX VMs To: Paolo Bonzini , Riku Voipio , Richard Henderson , Zhao Liu , "Michael S. Tsirkin" , Marcel Apfelbaum , Igor Mammedov , Ani Sinha Cc: =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= , Yanan Wang , Cornelia Huck , =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= , Eric Blake , Markus Armbruster , Marcelo Tosatti , rick.p.edgecombe@intel.com, kvm@vger.kernel.org, qemu-devel@nongnu.org References: <20241105062408.3533704-1-xiaoyao.li@intel.com> <20241105062408.3533704-46-xiaoyao.li@intel.com> <8cd78103-5f49-4cbd-814d-a03a82a59231@redhat.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: <8cd78103-5f49-4cbd-814d-a03a82a59231@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=198.175.65.21; envelope-from=xiaoyao.li@intel.com; helo=mgamail.intel.com X-Spam_score_int: -39 X-Spam_score: -4.0 X-Spam_bar: ---- X-Spam_report: (-4.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.34, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HK_RANDOM_ENVFROM=0.001, HK_RANDOM_FROM=0.781, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 11/5/2024 5:55 PM, Paolo Bonzini wrote: > On 11/5/24 07:23, Xiaoyao Li wrote: >> From: Sean Christopherson >> >> Don't get/put state of TDX VMs since accessing/mutating guest state of >> production TDs is not supported. >> >> Note, it will be allowed for a debug TD. Corresponding support will be >> introduced when debug TD support is implemented in the future. >> >> Signed-off-by: Sean Christopherson >> Signed-off-by: Xiaoyao Li >> Acked-by: Gerd Hoffmann > > This should be unnecessary now that QEMU has > kvm_mark_guest_state_protected(). Reverting this patch, we get: tdx: tdx: error: failed to set MSR 0x174 to 0x0 tdx: ../../../go/src/tdx/tdx-qemu/target/i386/kvm/kvm.c:3859: kvm_buf_set_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed. error: failed to set MSR 0x174 to 0x0 tdx: ../../../go/src/tdx/tdx-qemu/target/i386/kvm/kvm.c:3859: kvm_buf_set_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed. > Paolo > >> --- >>   target/i386/kvm/kvm.c | 11 +++++++++++ >>   1 file changed, 11 insertions(+) >> >> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c >> index c39e879a77e9..e47aa32233e6 100644 >> --- a/target/i386/kvm/kvm.c >> +++ b/target/i386/kvm/kvm.c >> @@ -5254,6 +5254,11 @@ int kvm_arch_put_registers(CPUState *cpu, int >> level, Error **errp) >>       assert(cpu_is_stopped(cpu) || qemu_cpu_is_self(cpu)); >> +    /* TODO: Allow accessing guest state for debug TDs. */ >> +    if (is_tdx_vm()) { >> +        return 0; >> +    } >> + >>       /* >>        * Put MSR_IA32_FEATURE_CONTROL first, this ensures the VM gets >> out of VMX >>        * root operation upon vCPU reset. kvm_put_msr_feature_control() >> should also >> @@ -5368,6 +5373,12 @@ int kvm_arch_get_registers(CPUState *cs, Error >> **errp) >>           error_setg_errno(errp, -ret, "Failed to get MP state"); >>           goto out; >>       } >> + >> +    /* TODO: Allow accessing guest state for debug TDs. */ >> +    if (is_tdx_vm()) { >> +        return 0; >> +    } >> + >>       ret = kvm_getput_regs(cpu, 0); >>       if (ret < 0) { >>           error_setg_errno(errp, -ret, "Failed to get general purpose >> registers"); >