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 1BF1DC28B20 for ; Wed, 2 Apr 2025 11:42:08 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tzwTM-0007yn-Fw; Wed, 02 Apr 2025 07:41:32 -0400 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 1tzwTJ-0007xJ-7B for qemu-devel@nongnu.org; Wed, 02 Apr 2025 07:41:29 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tzwTG-00049R-SO for qemu-devel@nongnu.org; Wed, 02 Apr 2025 07:41:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1743594084; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=F26kejczB0IcvMC9uwew5ia4bJQR9YG97iffe6dCF9k=; b=GaH+BbAigB6Onp/wRSEamEnOISlUews2G/bzuO8HMdB6R3vAva0U69l+36tbEV5r2i3KhD DTZi6gTt2BOjbEO6bltoyd4r7pgPtEGB8bUwgVyGCklm9FwZHwcDFY6xfsffKFuIM/x1n6 XvkyNrvnwS1AmQEfML+AwlPlk7Pm8oc= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-610-oV5Y6yZePlyefDgH-YTdIQ-1; Wed, 02 Apr 2025 07:41:22 -0400 X-MC-Unique: oV5Y6yZePlyefDgH-YTdIQ-1 X-Mimecast-MFC-AGG-ID: oV5Y6yZePlyefDgH-YTdIQ_1743594081 Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E6AE91800EC5; Wed, 2 Apr 2025 11:41:19 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.12]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 618471956094; Wed, 2 Apr 2025 11:41:14 +0000 (UTC) Date: Wed, 2 Apr 2025 12:41:11 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Xiaoyao Li Cc: Paolo Bonzini , "Michael S. Tsirkin" , Markus Armbruster , Francesco Lavra , Marcelo Tosatti , qemu-devel@nongnu.org, Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Rick Edgecombe Subject: Re: [PATCH v8 08/55] i386/tdx: Initialize TDX before creating TD vcpus Message-ID: References: <20250401130205.2198253-1-xiaoyao.li@intel.com> <20250401130205.2198253-9-xiaoyao.li@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250401130205.2198253-9-xiaoyao.li@intel.com> User-Agent: Mutt/2.2.13 (2024-03-09) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.153, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Apr 01, 2025 at 09:01:18AM -0400, Xiaoyao Li wrote: > Invoke KVM_TDX_INIT_VM in kvm_arch_pre_create_vcpu() that > KVM_TDX_INIT_VM configures global TD configurations, e.g. the canonical > CPUID config, and must be executed prior to creating vCPUs. > > Use kvm_x86_arch_cpuid() to setup the CPUID settings for TDX VM. > > Note, this doesn't address the fact that QEMU may change the CPUID > configuration when creating vCPUs, i.e. punts on refactoring QEMU to > provide a stable CPUID config prior to kvm_arch_init(). > > Signed-off-by: Xiaoyao Li > Acked-by: Gerd Hoffmann > Acked-by: Markus Armbruster > --- > Changes in v8: > - Drop the code that initializes cpu->kvm_state before > kvm_arch_pre_create_vcpu() because it's not needed anymore. > > Changes in v7: > - Add comments to explain why KVM_TDX_INIT_VM should retry on -EAGAIN; > - Add retry limit of 10000 times for -EAGAIN on KVM_TDX_INIT_VM; > > Changes in v6: > - setup xfam explicitly to fit with new uapi; > - use tdx_caps->cpuid to filter the input of cpuids because now KVM only > allows the leafs that reported via KVM_TDX_GET_CAPABILITIES; > > Changes in v4: > - mark init_vm with g_autofree() and use QEMU_LOCK_GUARD() to eliminate > the goto labels; (Daniel) > Changes in v3: > - Pass @errp in tdx_pre_create_vcpu() and pass error info to it. (Daniel) > --- > target/i386/kvm/kvm.c | 16 +++--- > target/i386/kvm/kvm_i386.h | 5 ++ > target/i386/kvm/meson.build | 2 +- > target/i386/kvm/tdx-stub.c | 10 ++++ > target/i386/kvm/tdx.c | 105 ++++++++++++++++++++++++++++++++++++ > target/i386/kvm/tdx.h | 6 +++ > 6 files changed, 137 insertions(+), 7 deletions(-) > create mode 100644 target/i386/kvm/tdx-stub.c > diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c > index 16f67e18ae78..0afaf739c09f 100644 > --- a/target/i386/kvm/tdx.c > +++ b/target/i386/kvm/tdx.c > +int tdx_pre_create_vcpu(CPUState *cpu, Error **errp) > +{ > + X86CPU *x86cpu = X86_CPU(cpu); > + CPUX86State *env = &x86cpu->env; > + g_autofree struct kvm_tdx_init_vm *init_vm = NULL; > + Error *local_err = NULL; > + int retry = 10000; > + int r = 0; > + > + QEMU_LOCK_GUARD(&tdx_guest->lock); > + if (tdx_guest->initialized) { > + return r; > + } > + > + init_vm = g_malloc0(sizeof(struct kvm_tdx_init_vm) + > + sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES); > + > + r = setup_td_xfam(x86cpu, errp); > + if (r) { > + return r; > + } > + > + init_vm->cpuid.nent = kvm_x86_build_cpuid(env, init_vm->cpuid.entries, 0); > + tdx_filter_cpuid(&init_vm->cpuid); > + > + init_vm->attributes = tdx_guest->attributes; > + init_vm->xfam = tdx_guest->xfam; > + > + /* > + * KVM_TDX_INIT_VM gets -EAGAIN when KVM side SEAMCALL(TDH_MNG_CREATE) > + * gets TDX_RND_NO_ENTROPY due to Random number generation (e.g., RDRAND or > + * RDSEED) is busy. > + * > + * Retry for the case. > + */ > + do { > + error_free(local_err); > + local_err = NULL; > + r = tdx_vm_ioctl(KVM_TDX_INIT_VM, 0, init_vm, &local_err); > + } while (r == -EAGAIN && --retry); > + > + if (r < 0) { > + if (!retry) { > + error_report("Hardware RNG (Random Number Generator) is busy " > + "occupied by someone (via RDRAND/RDSEED) maliciously, " > + "which leads to KVM_TDX_INIT_VM keeping failure " > + "due to lack of entropy."); This needs to be error_append_hint(local_err, ....); so that this message gets associated with the error object that is propagated, and the top level will print it all at once. > + } > + error_propagate(errp, local_err); > + return r; > + } > + > + tdx_guest->initialized = true; > + > + return 0; > +} With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|