From patchwork Tue Aug 30 13:37:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Kuznetsov X-Patchwork-Id: 12959372 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 53E24ECAAD4 for ; Tue, 30 Aug 2022 13:41:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231168AbiH3Nlo (ORCPT ); Tue, 30 Aug 2022 09:41:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45242 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229510AbiH3NlJ (ORCPT ); Tue, 30 Aug 2022 09:41:09 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81E5C11F for ; Tue, 30 Aug 2022 06:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661866738; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lrKJCo4aLdbt0m3uSjnwcM0QaFSfX/crWfaShd2ZxUM=; b=F9RQcIcL6e+DVkCB8wqtEv2khiho5nUrxkG78sJfp40eVabmRSQQNEv15wdLXVl0r+Nsxr 0RiweJQwKNMoKMDHzV0KyuF0qnQ8O40KbqmikZx1T8z3OPV3qBKYZ2CX9x53d53VlcAvFv 62RguyduVAOoOPi22rSwrReh0uaMQVo= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-248-aANp1kb7M0Kb5i8YkcPbsg-1; Tue, 30 Aug 2022 09:38:55 -0400 X-MC-Unique: aANp1kb7M0Kb5i8YkcPbsg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D51CC2999B48; Tue, 30 Aug 2022 13:38:54 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.40.194.232]) by smtp.corp.redhat.com (Postfix) with ESMTP id C21F72166B26; Tue, 30 Aug 2022 13:38:52 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org, Paolo Bonzini Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Michael Kelley , Yuan Yao , Maxim Levitsky , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v6 29/33] KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config() Date: Tue, 30 Aug 2022 15:37:33 +0200 Message-Id: <20220830133737.1539624-30-vkuznets@redhat.com> In-Reply-To: <20220830133737.1539624-1-vkuznets@redhat.com> References: <20220830133737.1539624-1-vkuznets@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org As a preparation to reusing the result of setup_vmcs_config() for setting up nested VMX control MSRs, move LOAD_IA32_PERF_GLOBAL_CTRL errata handling to vmx_vmexit_ctrl()/vmx_vmentry_ctrl() and print the warning from hardware_setup(). While it seems reasonable to not expose LOAD_IA32_PERF_GLOBAL_CTRL controls to L1 hypervisor on buggy CPUs, such change would inevitably break live migration from older KVMs where the controls are exposed. Keep the status quo for now, L1 hypervisor itself is supposed to take care of the errata. Reviewed-by: Maxim Levitsky Signed-off-by: Vitaly Kuznetsov Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/vmx.c | 59 +++++++++++++++++++++++++----------------- 1 file changed, 35 insertions(+), 24 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0a8798ec49e8..7b415d2fb2de 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2493,6 +2493,30 @@ static bool cpu_has_sgx(void) return cpuid_eax(0) >= 0x12 && (cpuid_eax(0x12) & BIT(0)); } +/* + * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they + * can't be used due to errata where VM Exit may incorrectly clear + * IA32_PERF_GLOBAL_CTRL[34:32]. Work around the errata by using the + * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL. + */ +static bool cpu_has_perf_global_ctrl_bug(void) +{ + if (boot_cpu_data.x86 == 0x6) { + switch (boot_cpu_data.x86_model) { + case INTEL_FAM6_NEHALEM_EP: /* AAK155 */ + case INTEL_FAM6_NEHALEM: /* AAP115 */ + case INTEL_FAM6_WESTMERE: /* AAT100 */ + case INTEL_FAM6_WESTMERE_EP: /* BC86,AAY89,BD102 */ + case INTEL_FAM6_NEHALEM_EX: /* BA97 */ + return true; + default: + break; + } + } + + return false; +} + static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, u32 msr, u32 *result) { @@ -2648,30 +2672,6 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf, _vmexit_control &= ~x_ctrl; } - /* - * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they - * can't be used due to an errata where VM Exit may incorrectly clear - * IA32_PERF_GLOBAL_CTRL[34:32]. Workaround the errata by using the - * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL. - */ - if (boot_cpu_data.x86 == 0x6) { - switch (boot_cpu_data.x86_model) { - case INTEL_FAM6_NEHALEM_EP: /* AAK155 */ - case INTEL_FAM6_NEHALEM: /* AAP115 */ - case INTEL_FAM6_WESTMERE: /* AAT100 */ - case INTEL_FAM6_WESTMERE_EP: /* BC86,AAY89,BD102 */ - case INTEL_FAM6_NEHALEM_EX: /* BA97 */ - _vmentry_control &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; - _vmexit_control &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; - pr_warn_once("kvm: VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL " - "does not work properly. Using workaround\n"); - break; - default: - break; - } - } - - rdmsr(MSR_IA32_VMX_BASIC, vmx_msr_low, vmx_msr_high); /* IA-32 SDM Vol 3B: VMCS size is never greater than 4kB. */ @@ -4267,6 +4267,9 @@ static u32 vmx_vmentry_ctrl(void) VM_ENTRY_LOAD_IA32_EFER | VM_ENTRY_IA32E_MODE); + if (cpu_has_perf_global_ctrl_bug()) + vmentry_ctrl &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; + return vmentry_ctrl; } @@ -4284,6 +4287,10 @@ static u32 vmx_vmexit_ctrl(void) if (vmx_pt_mode_is_system()) vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP | VM_EXIT_CLEAR_IA32_RTIT_CTL); + + if (cpu_has_perf_global_ctrl_bug()) + vmexit_ctrl &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; + /* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */ return vmexit_ctrl & ~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER); @@ -8190,6 +8197,10 @@ static __init int hardware_setup(void) if (setup_vmcs_config(&vmcs_config, &vmx_capability) < 0) return -EIO; + if (cpu_has_perf_global_ctrl_bug()) + pr_warn_once("kvm: VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL " + "does not work properly. Using workaround\n"); + if (boot_cpu_has(X86_FEATURE_NX)) kvm_enable_efer_bits(EFER_NX);