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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4ABE4C43334 for ; Wed, 29 Jun 2022 15:09:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234007AbiF2PJJ (ORCPT ); Wed, 29 Jun 2022 11:09:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234075AbiF2PHe (ORCPT ); Wed, 29 Jun 2022 11:07:34 -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 ESMTP id E349E36B7A for ; Wed, 29 Jun 2022 08:07:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656515246; 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=tR9oU39KRQAoB6WE5ZpPR1z9CGB7uFUw7cvsARqGFBc=; b=LrqD8KM7KEFvmxInyvNh1jJMPzvP1X24Htzkxoa8l/y6jkIDAZFK2vXrdoPxU7EHPpR2Jh t99FPiCRHZBdJbAiTvDNCweCbaOHJ+rWAej+W9RZjKfM88XAUwB16fzQ4/2c4luCHwsQer iY11HcleLYO/cvMHR+Z18l5nYM8oub8= 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-382-1nAnAriMOyeDp7vepwGLog-1; Wed, 29 Jun 2022 11:07:25 -0400 X-MC-Unique: 1nAnAriMOyeDp7vepwGLog-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 50F9A3C01D90; Wed, 29 Jun 2022 15:07:23 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.40.192.126]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0AA4B40EC002; Wed, 29 Jun 2022 15:07:20 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org, Paolo Bonzini , Sean Christopherson Cc: Anirudh Rayabharam , Wanpeng Li , Jim Mattson , Maxim Levitsky , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 23/28] KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config() Date: Wed, 29 Jun 2022 17:06:20 +0200 Message-Id: <20220629150625.238286-24-vkuznets@redhat.com> In-Reply-To: <20220629150625.238286-1-vkuznets@redhat.com> References: <20220629150625.238286-1-vkuznets@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 know, L1 hypervisor itself is supposed to take care of the errata. Signed-off-by: Vitaly Kuznetsov --- arch/x86/kvm/vmx/vmx.c | 62 ++++++++++++++++++++++++++---------------- 1 file changed, 38 insertions(+), 24 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index fb58b0be953d..5f7ef1f8d2c6 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2416,6 +2416,31 @@ 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 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. + */ +static bool cpu_has_perf_global_ctrl_bug(void) +{ + if (boot_cpu_data.x86 == 0x6) { + switch (boot_cpu_data.x86_model) { + case 26: /* AAK155 */ + case 30: /* AAP115 */ + case 37: /* AAT100 */ + case 44: /* BC86,AAY89,BD102 */ + case 46: /* BA97 */ + return true; + default: + break; + } + } + + return false; +} + + static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, u32 msr, u32 *result) { @@ -2572,30 +2597,6 @@ 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 26: /* AAK155 */ - case 30: /* AAP115 */ - case 37: /* AAT100 */ - case 44: /* BC86,AAY89,BD102 */ - case 46: /* 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. */ @@ -4188,6 +4189,10 @@ 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; } @@ -4202,6 +4207,10 @@ 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); @@ -8117,6 +8126,11 @@ 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); -- 2.35.3