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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 94CB5C07E94 for ; Fri, 4 Jun 2021 07:33:05 +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 C461061417 for ; Fri, 4 Jun 2021 07:33:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C461061417 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:48104 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lp4KF-0002CC-Sv for qemu-devel@archiver.kernel.org; Fri, 04 Jun 2021 03:33:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48672) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lp4JF-0001Vb-2B for qemu-devel@nongnu.org; Fri, 04 Jun 2021 03:32:02 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:45406) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lp4JA-0006pF-MS for qemu-devel@nongnu.org; Fri, 04 Jun 2021 03:32:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1622791915; h=from:from: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=aFSvdBRdHmdiDfdiYRlzyHHO0LVr2me6UFfbRzXTCPQ=; b=iShMOqvv5oE9zr8YSqyS+N4I3vlpo3DTxL9NVY+5qq5PMz6Otfaf1OL8tHIQlPmD2Z5RHB CtJfnGx7TpGjtxnH3MunlCW+3onWaNbs8p2l97FEKmFXrOFGK4Y+eHr9cTLnc4n05Voctb XBX2nJJp5Rddby/9QJED4PmuJJZ6214= Received: from mail-ej1-f69.google.com (mail-ej1-f69.google.com [209.85.218.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-332-qd2Vay7gOCC_E5vGFZOVvg-1; Fri, 04 Jun 2021 03:31:53 -0400 X-MC-Unique: qd2Vay7gOCC_E5vGFZOVvg-1 Received: by mail-ej1-f69.google.com with SMTP id w1-20020a1709064a01b02903f1e4e947c9so1599717eju.16 for ; Fri, 04 Jun 2021 00:31:53 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=aFSvdBRdHmdiDfdiYRlzyHHO0LVr2me6UFfbRzXTCPQ=; b=lAg1Ff1TfZqtlKJZEcgKtjBer1JoD6DKvh3mmbNNFUDcJWUffMrAhfsyQqNqYLcFvz M8PRPM9z7hoZi1VhZUlOaAZ/7TvtLSiSnvJ9d1RNMo0BWByEbjP/y0ebC6tb3xHzh4+s +1IKfAr0ZgfYBeN1xI4UfaTSt8OXCw0DacST1azCeYKJVE9jw+Rhs2uaCBva/nITsrAg ylenXAwhQGatRer7D4bWRJ27H5giv+Y7aQ6TGROAcQ9D2duR68v5WHtPuWz9pcZLYX57 JKgCJuiw/a/PzeaywIXf7BCWys/tZIEeGSooSFJ6jhmhte9XcV2AAbrc8eYQ28JDU1ZJ JU5g== X-Gm-Message-State: AOAM5327KdhG7EPs1pkEHscSaB2a1eg+XhhuWUCJfGS9shochkyvoMGF rn87m/AOoD2knRCMfj+Od5CeBPvezKEHz0J1N3IOMAsRAmf9+wVb8N1NczO3whLIFYa+3LD61EZ mmPXqDDD0M7sfRWs= X-Received: by 2002:a17:906:22c8:: with SMTP id q8mr2857562eja.12.1622791912095; Fri, 04 Jun 2021 00:31:52 -0700 (PDT) X-Google-Smtp-Source: ABdhPJy0sQ+brg2gHD0UzYFYjW30Ip1NejGaSIlAzkgh2KEqfWKLDm+9BuikDCOxcFIxaxptuijgLg== X-Received: by 2002:a17:906:22c8:: with SMTP id q8mr2857553eja.12.1622791911869; Fri, 04 Jun 2021 00:31:51 -0700 (PDT) Received: from vitty.brq.redhat.com (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id n2sm2824305edi.32.2021.06.04.00.31.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Jun 2021 00:31:51 -0700 (PDT) From: Vitaly Kuznetsov To: Eduardo Habkost Subject: Re: [PATCH v7 5/9] i386: expand Hyper-V features during CPU feature expansion time In-Reply-To: <20210603224304.ctigvokfqbcsiy7g@habkost.net> References: <20210603114835.847451-1-vkuznets@redhat.com> <20210603114835.847451-6-vkuznets@redhat.com> <20210603224304.ctigvokfqbcsiy7g@habkost.net> Date: Fri, 04 Jun 2021 09:31:50 +0200 Message-ID: <874kee13x5.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=vkuznets@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Received-SPF: pass client-ip=170.10.133.124; envelope-from=vkuznets@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.37, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Marcelo Tosatti , qemu-devel@nongnu.org, Igor Mammedov Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Eduardo Habkost writes: > On Thu, Jun 03, 2021 at 01:48:31PM +0200, Vitaly Kuznetsov wrote: >> To make Hyper-V features appear in e.g. QMP query-cpu-model-expansion we >> need to expand and set the corresponding CPUID leaves early. Modify >> x86_cpu_get_supported_feature_word() to call newly intoduced Hyper-V >> specific kvm_hv_get_supported_cpuid() instead of >> kvm_arch_get_supported_cpuid(). We can't use kvm_arch_get_supported_cpuid() >> as Hyper-V specific CPUID leaves intersect with KVM's. >> >> Note, early expansion will only happen when KVM supports system wide >> KVM_GET_SUPPORTED_HV_CPUID ioctl (KVM_CAP_SYS_HYPERV_CPUID). >> >> Signed-off-by: Vitaly Kuznetsov >> --- >> target/i386/cpu.c | 4 ++++ >> target/i386/kvm/kvm-stub.c | 5 +++++ >> target/i386/kvm/kvm.c | 24 ++++++++++++++++++++---- >> target/i386/kvm/kvm_i386.h | 1 + >> 4 files changed, 30 insertions(+), 4 deletions(-) >> >> diff --git a/target/i386/cpu.c b/target/i386/cpu.c >> index b2d8e5713911..159b7aa8f073 100644 >> --- a/target/i386/cpu.c >> +++ b/target/i386/cpu.c >> @@ -5990,6 +5990,10 @@ void x86_cpu_expand_features(X86CPU *cpu, Error **errp) >> if (env->cpuid_xlevel2 == UINT32_MAX) { >> env->cpuid_xlevel2 = env->cpuid_min_xlevel2; >> } >> + >> + if (kvm_enabled()) { >> + kvm_hyperv_expand_features(cpu, errp); >> + } >> } >> >> /* >> diff --git a/target/i386/kvm/kvm-stub.c b/target/i386/kvm/kvm-stub.c >> index 92f49121b8fa..f6e7e4466e1a 100644 >> --- a/target/i386/kvm/kvm-stub.c >> +++ b/target/i386/kvm/kvm-stub.c >> @@ -39,3 +39,8 @@ bool kvm_hv_vpindex_settable(void) >> { >> return false; >> } >> + >> +bool kvm_hyperv_expand_features(X86CPU *cpu, Error **errp) >> +{ >> + abort(); >> +} >> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c >> index a5f8553af921..650fdd970d6e 100644 >> --- a/target/i386/kvm/kvm.c >> +++ b/target/i386/kvm/kvm.c >> @@ -1217,13 +1217,22 @@ static uint32_t hv_build_cpuid_leaf(CPUState *cs, uint32_t func, int reg) >> * of 'hv_passthrough' mode and fills the environment with all supported >> * Hyper-V features. >> */ >> -static bool hyperv_expand_features(CPUState *cs, Error **errp) >> +bool kvm_hyperv_expand_features(X86CPU *cpu, Error **errp) >> { >> - X86CPU *cpu = X86_CPU(cs); >> + CPUState *cs = CPU(cpu); >> >> if (!hyperv_enabled(cpu)) >> return true; >> >> + /* >> + * When kvm_hyperv_expand_features is called at CPU feature expansion >> + * time per-CPU kvm_state is not available yet so we can only proceed >> + * when KVM_CAP_SYS_HYPERV_CPUID is supported. >> + */ >> + if (!cs->kvm_state && >> + !kvm_check_extension(kvm_state, KVM_CAP_SYS_HYPERV_CPUID)) >> + return true; >> + >> if (cpu->hyperv_passthrough) { >> cpu->hyperv_vendor_id[0] = >> hv_cpuid_get_host(cs, HV_CPUID_VENDOR_AND_MAX_FUNCTIONS, R_EBX); >> @@ -1565,8 +1574,15 @@ int kvm_arch_init_vcpu(CPUState *cs) >> >> env->apic_bus_freq = KVM_APIC_BUS_FREQUENCY; >> >> - /* Paravirtualization CPUIDs */ >> - if (!hyperv_expand_features(cs, &local_err)) { >> + /* >> + * kvm_hyperv_expand_features() is called here for the second time in case >> + * KVM_CAP_SYS_HYPERV_CPUID is not supported. While we can't possibly handle >> + * 'query-cpu-model-expansion' in this case as we don't have a KVM vCPU to >> + * check which Hyper-V enlightenments are supported and which are not, we >> + * can still proceed and check/expand Hyper-V enlightenments here so legacy >> + * behavior is preserved. >> + */ > > Issue we might need to solve later: how can management software > differentiate "Hyper-V enlightenments are not supported at all" > from "we can't tell you which Hyper-V enlightenments are > available because KVM_CAP_SYS_HYPERV_CPUID is unavailable"? > In case we're not considering *very* old kernels, basic Hyper-V enlightenments should always be available so if 'query-cpu-model-expansion' doesn't give you anything (like now, pre-patch) then you treat this as 'QEMU can't tell me what's supported' and not like 'no Hyper-V enlightenments at all'. > >> + if (!kvm_hyperv_expand_features(cpu, &local_err)) { >> error_report_err(local_err); >> return -ENOSYS; >> } >> diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h >> index dc725083891c..54667b35f09c 100644 >> --- a/target/i386/kvm/kvm_i386.h >> +++ b/target/i386/kvm/kvm_i386.h >> @@ -47,6 +47,7 @@ bool kvm_has_x2apic_api(void); >> bool kvm_has_waitpkg(void); >> >> bool kvm_hv_vpindex_settable(void); >> +bool kvm_hyperv_expand_features(X86CPU *cpu, Error **errp); >> >> uint64_t kvm_swizzle_msi_ext_dest_id(uint64_t address); > > Reviewed-by: Eduardo Habkost Thanks! -- Vitaly