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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C76B4C43219 for ; Tue, 30 Apr 2019 17:33:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 982B42147A for ; Tue, 30 Apr 2019 17:33:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726155AbfD3Rdb (ORCPT ); Tue, 30 Apr 2019 13:33:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52750 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725930AbfD3Rdb (ORCPT ); Tue, 30 Apr 2019 13:33:31 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 01AFC3087945; Tue, 30 Apr 2019 17:33:31 +0000 (UTC) Received: from vitty.brq.redhat.com (ovpn-204-104.brq.redhat.com [10.40.204.104]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 69A8662926; Tue, 30 Apr 2019 17:33:29 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Sean Christopherson Subject: [PATCH] x86/kvm/mmu: reset MMU context when 32-bit guest switches PAE Date: Tue, 30 Apr 2019 19:33:26 +0200 Message-Id: <20190430173326.1956-1-vkuznets@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Tue, 30 Apr 2019 17:33:31 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 47c42e6b4192 ("KVM: x86: fix handling of role.cr4_pae and rename it to 'gpte_size'") introduced a regression: 32-bit PAE guests stopped working. The issue appears to be: when guest switches (enables) PAE we need to re-initialize MMU context (set context->root_level, do reset_rsvds_bits_mask(), ...) but init_kvm_tdp_mmu() doesn't do that because we threw away is_pae(vcpu) flag from mmu role. Restore it to kvm_mmu_extended_role (as we now don't need it in base role) to fix the issue. Fixes: 47c42e6b4192 ("KVM: x86: fix handling of role.cr4_pae and rename it to 'gpte_size'") Signed-off-by: Vitaly Kuznetsov --- - RFC: it was proven multiple times that mmu code is more complex than it appears (at least to me) :-) --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index a9d03af34030..c79abe7ca093 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -295,6 +295,7 @@ union kvm_mmu_extended_role { unsigned int valid:1; unsigned int execonly:1; unsigned int cr0_pg:1; + unsigned int cr4_pae:1; unsigned int cr4_pse:1; unsigned int cr4_pke:1; unsigned int cr4_smap:1; diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index e10962dfc203..d9c7b45d231f 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4781,6 +4781,7 @@ static union kvm_mmu_extended_role kvm_calc_mmu_role_ext(struct kvm_vcpu *vcpu) union kvm_mmu_extended_role ext = {0}; ext.cr0_pg = !!is_paging(vcpu); + ext.cr4_pae = !!is_pae(vcpu); ext.cr4_smep = !!kvm_read_cr4_bits(vcpu, X86_CR4_SMEP); ext.cr4_smap = !!kvm_read_cr4_bits(vcpu, X86_CR4_SMAP); ext.cr4_pse = !!is_pse(vcpu); -- 2.20.1