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 60BAFC433F5 for ; Sat, 1 Oct 2022 01:03:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233140AbiJABDL (ORCPT ); Fri, 30 Sep 2022 21:03:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232948AbiJABCQ (ORCPT ); Fri, 30 Sep 2022 21:02:16 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BEF83139F53 for ; Fri, 30 Sep 2022 18:00:21 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-3553d2d9d7fso52359177b3.5 for ; Fri, 30 Sep 2022 18:00:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date; bh=HY4Thk5xVyPi8wKWVdpWupQbepWNLCynruIllm630pU=; b=UMPvRXSU4HOXUmmnmc0jCi/0QPbsXPdSBTKgJqc25cCrOAQgtzf+tyOoZaBNLF9QMg n2b9DRSZpPSdhB7f8X8BG3gj3Ab9xz1/087i9IcnRTZEqBTGL7j6N386w3snyMlZApP4 eDCC4doRfm2dctlxOQilOfUCYiO2GG3IyJoqHMY+uSCGJjhkTDCXTiNeAxnrPTNOdcEL /l5eXYMr3GHQwFnfgq04c5YmsZeJAqhVXP3yMojrBVpADN9ciI0WLE2AfN/tc74m2V23 A1mN+3+oSe91kkpk6MnfzaT7FAeznCOH6k/auTehPLbixkHgvPtO39wpYb8hssFWUtoD ThSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date; bh=HY4Thk5xVyPi8wKWVdpWupQbepWNLCynruIllm630pU=; b=z7LYmZbh+WAWWqzk1Fv8EXsg8/6+cjbBF/o8yHs/YfjH6Sw3GnyIRzu++xinKHB0SJ 66XVNJXm46DS9gZF5xOVBiAPk6pizZ3QT3twP2f+zs8vbMN4hNBU0qqyQ5K7V0FT2KTc JSfPaFhxvG9y/pwCX3qhyT7hWLQcUOl+m+XGupQ9wbSCERAMs/a6hEFl/Iau5FnD5/FT KJSnZaMvcxJEUjVwXyIGMEoCXuoFPRYGKWO8BAjLzh7L1rQyFCeANv4fDHrrmjVOGYCs KVUUSvBxW37XuQl/yghLA5yO9INhRFaUUPtb4OYecvGEvQFWQd6BddsLwiJoh4P+754s ++bg== X-Gm-Message-State: ACrzQf0QLErU/O3A7OepnHPIsMbXhmxzTnDIBKAdfnDXIvrrw6WocntA g9EWrjNPURe4p5a+wFkhvLaOSWEK1jU= X-Google-Smtp-Source: AMsMyM6rWD4QbGIvONouo6zkfDiIWLguwc6s8vjrkpUamNM8RtGPhWMCVyL0s7k2Wdo+5V14cJnbWZR176Q= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a25:16d6:0:b0:6b1:4a12:b2f4 with SMTP id 205-20020a2516d6000000b006b14a12b2f4mr11014876ybw.217.1664586001024; Fri, 30 Sep 2022 18:00:01 -0700 (PDT) Reply-To: Sean Christopherson Date: Sat, 1 Oct 2022 00:59:08 +0000 In-Reply-To: <20221001005915.2041642-1-seanjc@google.com> Mime-Version: 1.0 References: <20221001005915.2041642-1-seanjc@google.com> X-Mailer: git-send-email 2.38.0.rc1.362.ged0d419d3c-goog Message-ID: <20221001005915.2041642-26-seanjc@google.com> Subject: [PATCH v4 25/32] KVM: SVM: Inhibit AVIC if vCPUs are aliased in logical mode From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Alejandro Jimenez , Suravee Suthikulpanit , Maxim Levitsky , Li RongQing Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Inhibit SVM's AVIC if multiple vCPUs are aliased to the same logical ID. Architecturally, all CPUs whose logical ID matches the MDA are supposed to receive the interrupt; overwriting existing entries in AVIC's logical=>physical map can result in missed IPIs. Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Signed-off-by: Sean Christopherson --- arch/x86/include/asm/kvm_host.h | 6 ++++++ arch/x86/kvm/lapic.c | 5 +++++ arch/x86/kvm/svm/avic.c | 3 ++- 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 171e38b94c89..4fd06965c773 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1159,6 +1159,12 @@ enum kvm_apicv_inhibit { * APIC base. For simplicity, this is sticky. */ APICV_INHIBIT_REASON_X2APIC, + + /* + * AVIC is disabled because not all vCPUs with a valid LDR have a 1:1 + * mapping between logical ID and vCPU. + */ + APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED, }; struct kvm_arch { diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index f6f328d36ae2..9b3af49d2524 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -391,6 +391,11 @@ void kvm_recalculate_apic_map(struct kvm *kvm) else kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED); + if (!new || new->logical_mode == KVM_APIC_MODE_MAP_DISABLED) + kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED); + else + kvm_clear_apicv_inhibit(kvm, APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED); + old = rcu_dereference_protected(kvm->arch.apic_map, lockdep_is_held(&kvm->arch.apic_map_lock)); rcu_assign_pointer(kvm->arch.apic_map, new); diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c index 2908adc79ea6..27d5abc15a91 100644 --- a/arch/x86/kvm/svm/avic.c +++ b/arch/x86/kvm/svm/avic.c @@ -968,7 +968,8 @@ bool avic_check_apicv_inhibit_reasons(enum kvm_apicv_inhibit reason) BIT(APICV_INHIBIT_REASON_PHYSICAL_ID_ALIASED) | BIT(APICV_INHIBIT_REASON_APIC_ID_MODIFIED) | BIT(APICV_INHIBIT_REASON_APIC_BASE_MODIFIED) | - BIT(APICV_INHIBIT_REASON_X2APIC); + BIT(APICV_INHIBIT_REASON_X2APIC) | + BIT(APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED); return supported & BIT(reason); } -- 2.38.0.rc1.362.ged0d419d3c-goog