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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 B1199C35247 for ; Thu, 6 Feb 2020 23:07:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8200E214AF for ; Thu, 6 Feb 2020 23:07:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727524AbgBFXHb (ORCPT ); Thu, 6 Feb 2020 18:07:31 -0500 Received: from mga02.intel.com ([134.134.136.20]:34047 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726509AbgBFXHb (ORCPT ); Thu, 6 Feb 2020 18:07:31 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Feb 2020 15:07:30 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,411,1574150400"; d="scan'208";a="225391166" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by fmsmga007.fm.intel.com with ESMTP; 06 Feb 2020 15:07:30 -0800 Date: Thu, 6 Feb 2020 15:07:30 -0800 From: Sean Christopherson To: Paolo Bonzini Cc: Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/7] KVM: x86/mmu: Fix struct guest_walker arrays for 5-level paging Message-ID: <20200206230730.GA24556@linux.intel.com> References: <20200206220836.22743-1-sean.j.christopherson@intel.com> <20200206220836.22743-3-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200206220836.22743-3-sean.j.christopherson@intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 06, 2020 at 02:08:31PM -0800, Sean Christopherson wrote: > Define PT_MAX_FULL_LEVELS as PT64_ROOT_MAX_LEVEL, i.e. 5, to fix shadow > paging for 5-level guest page tables. PT_MAX_FULL_LEVELS is used to > size the arrays that track guest pages table information, i.e. using a > "max levels" of 4 causes KVM to access garbage beyond the end of an > array when querying state for level 5 entries. E.g. FNAME(gpte_changed) > will read garbage and most likely return %true for a level 5 entry, > soft-hanging the guest because FNAME(fetch) will restart the guest > instead of creating SPTEs because it thinks the guest PTE has changed. > > Fixes: 855feb673640 ("KVM: MMU: Add 5 level EPT & Shadow page table support.") > Cc: stable@vger.kernel.org > Signed-off-by: Sean Christopherson > --- > arch/x86/kvm/mmu/paging_tmpl.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h > index 4e1ef0473663..6b15b58f3ecc 100644 > --- a/arch/x86/kvm/mmu/paging_tmpl.h > +++ b/arch/x86/kvm/mmu/paging_tmpl.h > @@ -33,7 +33,7 @@ > #define PT_GUEST_ACCESSED_SHIFT PT_ACCESSED_SHIFT > #define PT_HAVE_ACCESSED_DIRTY(mmu) true > #ifdef CONFIG_X86_64 > - #define PT_MAX_FULL_LEVELS 4 > + #define PT_MAX_FULL_LEVELS PT64_ROOT_MAX_LEVEL > #define CMPXCHG cmpxchg > #else > #define CMPXCHG cmpxchg64 > @@ -66,7 +66,7 @@ > #define PT_GUEST_ACCESSED_SHIFT 8 > #define PT_HAVE_ACCESSED_DIRTY(mmu) ((mmu)->ept_ad) > #define CMPXCHG cmpxchg64 > - #define PT_MAX_FULL_LEVELS 4 > + #define PT_MAX_FULL_LEVELS PT64_ROOT_MAX_LEVEL Doh, the nested EPT change belongs in the next patch. I'll retest tomorrow and send a v2 when by brain is less mushy. > #else > #error Invalid PTTYPE value > #endif > -- > 2.24.1 >