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 02EE6C433F5 for ; Thu, 24 Mar 2022 11:14:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349711AbiCXLPu (ORCPT ); Thu, 24 Mar 2022 07:15:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349692AbiCXLPo (ORCPT ); Thu, 24 Mar 2022 07:15:44 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 2912872E2C for ; Thu, 24 Mar 2022 04:14:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648120452; 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=Lkor8/fgDn8C4k+CI3MJ8f7UXm4ww7ZYHLZLrk4A3Mg=; b=SCfQPQsaP1trzlR4B1hEUTrYt7Ka1BXjuHeU4Vz2DsgTwEzsfOT+HxLYz1zT454m81Dnt0 K/zfjo7RAJnT43uNNwA8+VIhVpWzvGXpCuI804Tpz/VlVVt42SCtxkM+JkOolcYP2JyzBh ioGKq8FJZ6ZSboYatX5Gyhic4TbCkZk= 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-563-RR2YE1LdM72fscDxndmEmQ-1; Thu, 24 Mar 2022 07:14:07 -0400 X-MC-Unique: RR2YE1LdM72fscDxndmEmQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 87E482A2AD44; Thu, 24 Mar 2022 11:14:06 +0000 (UTC) Received: from starship (unknown [10.40.194.231]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2F9869D46; Thu, 24 Mar 2022 11:13:58 +0000 (UTC) Message-ID: Subject: Re: [RFCv2 PATCH 04/12] KVM: SVM: Update max number of vCPUs supported for x2AVIC mode From: Maxim Levitsky To: Suravee Suthikulpanit , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: pbonzini@redhat.com, seanjc@google.com, joro@8bytes.org, jon.grimm@amd.com, wei.huang2@amd.com, terry.bowman@amd.com Date: Thu, 24 Mar 2022 13:13:57 +0200 In-Reply-To: <20220308163926.563994-5-suravee.suthikulpanit@amd.com> References: <20220308163926.563994-1-suravee.suthikulpanit@amd.com> <20220308163926.563994-5-suravee.suthikulpanit@amd.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5 (3.36.5-2.fc32) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2022-03-08 at 10:39 -0600, Suravee Suthikulpanit wrote: > xAVIC and x2AVIC modes can support diffferent number of vcpus. > Update existing logics to support each mode accordingly. > > Also, modify the maximum physical APIC ID for AVIC to 255 to reflect > the actual value supported by the architecture. > > Signed-off-by: Suravee Suthikulpanit > --- > arch/x86/include/asm/svm.h | 12 +++++++++--- > arch/x86/kvm/svm/avic.c | 8 +++++--- > 2 files changed, 14 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h > index 7a7a2297165b..681a348a9365 100644 > --- a/arch/x86/include/asm/svm.h > +++ b/arch/x86/include/asm/svm.h > @@ -250,10 +250,16 @@ enum avic_ipi_failure_cause { > > > /* > - * 0xff is broadcast, so the max index allowed for physical APIC ID > - * table is 0xfe. APIC IDs above 0xff are reserved. > + * For AVIC, the max index allowed for physical APIC ID > + * table is 0xff (255). > */ > -#define AVIC_MAX_PHYSICAL_ID_COUNT 0xff This should be 0xFE, since index 0xFF is reserved in AVIC mode. It used to work because (see below) check used to be '>=', but I do like that you switched to '>' check instead. > +#define AVIC_MAX_PHYSICAL_ID 0XFFULL > + > +/* > + * For x2AVIC, the max index allowed for physical APIC ID > + * table is 0x1ff (511). > + */ > +#define X2AVIC_MAX_PHYSICAL_ID 0x1FFUL > > #define AVIC_HPA_MASK ~((0xFFFULL << 52) | 0xFFF) > #define VMCB_AVIC_APIC_BAR_MASK 0xFFFFFFFFFF000ULL > diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c > index 49b185f0d42e..f128b0189d4a 100644 > --- a/arch/x86/kvm/svm/avic.c > +++ b/arch/x86/kvm/svm/avic.c > @@ -183,7 +183,7 @@ void avic_init_vmcb(struct vcpu_svm *svm) > vmcb->control.avic_backing_page = bpa & AVIC_HPA_MASK; > vmcb->control.avic_logical_id = lpa & AVIC_HPA_MASK; > vmcb->control.avic_physical_id = ppa & AVIC_HPA_MASK; > - vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID_COUNT; > + vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID; > vmcb->control.avic_vapic_bar = APIC_DEFAULT_PHYS_BASE & VMCB_AVIC_APIC_BAR_MASK; > > if (kvm_apicv_activated(svm->vcpu.kvm)) > @@ -198,7 +198,8 @@ static u64 *avic_get_physical_id_entry(struct kvm_vcpu *vcpu, > u64 *avic_physical_id_table; > struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm); > > - if (index >= AVIC_MAX_PHYSICAL_ID_COUNT) This is the check I am talking about > + if ((avic_mode == AVIC_MODE_X1 && index > AVIC_MAX_PHYSICAL_ID) || > + (avic_mode == AVIC_MODE_X2 && index > X2AVIC_MAX_PHYSICAL_ID)) > return NULL; I would probably like to ask to move this check to a function, but I see that avic_get_physical_id_entry is only used in avic_handle_apic_id_update in addition to avic_init_backing_page which has this check, and I will sooner or later remove the anywat broken avic_handle_apic_id_update and inline the avic_get_physical_id_entry probably so no need to do this. > > avic_physical_id_table = page_address(kvm_svm->avic_physical_id_table_page); > @@ -245,7 +246,8 @@ static int avic_init_backing_page(struct kvm_vcpu *vcpu) > int id = vcpu->vcpu_id; > struct vcpu_svm *svm = to_svm(vcpu); > > - if (id >= AVIC_MAX_PHYSICAL_ID_COUNT) > + if ((avic_mode == AVIC_MODE_X1 && id > AVIC_MAX_PHYSICAL_ID) || > + (avic_mode == AVIC_MODE_X2 && id > X2AVIC_MAX_PHYSICAL_ID)) > return -EINVAL; > > if (!vcpu->arch.apic->regs) So except the off-by-one error in AVIC_MAX_PHYSICAL_ID_COUNT: Reviewed-by: Maxim Levitsky Best regards, Maxim Levitsky