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 24C92C54EBD for ; Sun, 8 Jan 2023 14:26:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233044AbjAHOZ4 (ORCPT ); Sun, 8 Jan 2023 09:25:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60546 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231295AbjAHOZx (ORCPT ); Sun, 8 Jan 2023 09:25:53 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C34FFAC4 for ; Sun, 8 Jan 2023 06:25:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673187905; 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=ksiCTFiq5acBPWOANtiLHvB+WxH84jzu0HNhRmaLORc=; b=LdQj2i78B3aMDuv7490Bs232YR7seWopaPYFlGWI7rWquxoH9SA/dSCFR95WzBi5Rt9Qy6 7BCr74ezk1QZRYwXNsIGoqxFPUlWnWac3tKEc7ivPmz59KFCiqp4QwhVZ3C4/Ra5VO2yew 4medSYgupIAu5JfiBuAyzl+SvFjz4Pg= Received: from mail-ej1-f70.google.com (mail-ej1-f70.google.com [209.85.218.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-659-pchQpAJ1PZaKxLnGmjNf-A-1; Sun, 08 Jan 2023 09:25:04 -0500 X-MC-Unique: pchQpAJ1PZaKxLnGmjNf-A-1 Received: by mail-ej1-f70.google.com with SMTP id xh12-20020a170906da8c00b007413144e87fso3889670ejb.14 for ; Sun, 08 Jan 2023 06:25:03 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:user-agent:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=ksiCTFiq5acBPWOANtiLHvB+WxH84jzu0HNhRmaLORc=; b=fN+Ai8xrA0kqzNXON1P9LIB4eKqrVLS05O8ZzowyPFX5r+zdgWAi/8pWer5YTeuBV8 dnCA0OoqmdusbBBPFqg3UZi7KhUYDBni/EljxSBx0/12PY403eJbUpK+GN2GTAs8ONSj g9XY63qnjbdT/0XDElDK8kiHPUhvQs9Fz5Ejezbq+o9+t/M4OPxnbUbLGKzw/5+mik83 J7XdTgHKwj6m//JgLwkau1gAY6ux8I50aJ0mc/aNf6/k4qNjvOxBiK6aGSJpI9MGYszU 2eiudj+3zDwlByPGWndIQXk53S03vUjBOCToaiMp9lcTz6oC3zJmPRvN8QyhOgKe8RoY O/cQ== X-Gm-Message-State: AFqh2kq/b+nShybGzafPwpJtC5WAvBYr+DPTV1M/Jr73ubQDiZuI+W+d JQr11e3E2lpOOmaq4vhk+uqQcBiMim3O6RbBVL/6mn2VBgwQD624MYpPuu2OUGHZP8BB1qWCkIs 2KeV1TY/JC3M/AScXnPy71xdO X-Received: by 2002:a17:907:c71b:b0:7c1:67ca:56f5 with SMTP id ty27-20020a170907c71b00b007c167ca56f5mr58723209ejc.15.1673187903070; Sun, 08 Jan 2023 06:25:03 -0800 (PST) X-Google-Smtp-Source: AMrXdXuSOtqdC4idlnrW13cj2BA8d1/Io1UUTNfkqZjvpPpxfSYnUWJWJLNJVX1E+OmlahEQx9AuMw== X-Received: by 2002:a17:907:c71b:b0:7c1:67ca:56f5 with SMTP id ty27-20020a170907c71b00b007c167ca56f5mr58723202ejc.15.1673187902915; Sun, 08 Jan 2023 06:25:02 -0800 (PST) Received: from starship ([89.237.103.62]) by smtp.gmail.com with ESMTPSA id n12-20020a1709062bcc00b007ae38d837c5sm2563068ejg.174.2023.01.08.06.25.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Jan 2023 06:25:02 -0800 (PST) Message-ID: <85f6ece15147bac18468662c411f266374365ed3.camel@redhat.com> Subject: Re: [PATCH v5 03/33] KVM: SVM: Flush the "current" TLB when activating AVIC From: Maxim Levitsky To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Alejandro Jimenez , Suravee Suthikulpanit , Li RongQing , Greg Edwards Date: Sun, 08 Jan 2023 16:25:00 +0200 In-Reply-To: <20230106011306.85230-4-seanjc@google.com> References: <20230106011306.85230-1-seanjc@google.com> <20230106011306.85230-4-seanjc@google.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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2023-01-06 at 01:12 +0000, Sean Christopherson wrote: > Flush the TLB when activating AVIC as the CPU can insert into the TLB > while AVIC is "locally" disabled. KVM doesn't treat "APIC hardware > disabled" as VM-wide AVIC inhibition, and so when a vCPU has its APIC > hardware disabled, AVIC is not guaranteed to be inhibited. As a result, > KVM may create a valid NPT mapping for the APIC base, which the CPU can > cache as a non-AVIC translation. > > Note, Intel handles this in vmx_set_virtual_apic_mode(). > > Reviewed-by: Paolo Bonzini > Cc: stable@vger.kernel.org > Signed-off-by: Sean Christopherson > --- > arch/x86/kvm/svm/avic.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c > index 6919dee69f18..712330b80891 100644 > --- a/arch/x86/kvm/svm/avic.c > +++ b/arch/x86/kvm/svm/avic.c > @@ -86,6 +86,12 @@ static void avic_activate_vmcb(struct vcpu_svm *svm) > /* Disabling MSR intercept for x2APIC registers */ > svm_set_x2apic_msr_interception(svm, false); > } else { > + /* > + * Flush the TLB, the guest may have inserted a non-APIC > + * mapping into the TLB while AVIC was disabled. > + */ > + kvm_make_request(KVM_REQ_TLB_FLUSH_CURRENT, &svm->vcpu); > + > /* For xAVIC and hybrid-xAVIC modes */ > vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID; > /* Enabling MSR intercept for x2APIC registers */ Reviewed-by: Maxim Levitsky Best regards, Maxim Levitsky