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 0AB22C0015E for ; Wed, 5 Jul 2023 14:17:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232291AbjGEORj (ORCPT ); Wed, 5 Jul 2023 10:17:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34960 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231815AbjGEORe (ORCPT ); Wed, 5 Jul 2023 10:17:34 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A328ACF; Wed, 5 Jul 2023 07:17:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1688566653; x=1720102653; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=dxaLcFyIX6B15hyemUTtg4E+16m6duFMnhi44AUxrxk=; b=aa7cDsX5UbUuummWdbY055EtQEHtGMh65yQUfcuRSzhSlPt1rxts1wP2 bNlhjxDv7hd8o8VzzteflO1ezzrG3QnOWIiIejRhXqL4CPM5dD7ax6lY3 e/e1fqb0vC3eUTE5BzI5V9z25fvlZXRFcWjFIuQdGRcBy8DuaI/LbJgYf rJQwAbGlI1c83nlp3fdDma+qPEcRygi93zBJyjIlVMfae1NQZPwMKhVcp vHrGbXz51LGIZsOZwAr++lqucHt07iGdm+MSDdjleNCowe+mSWIfekDru E8wXbecyjVHWdbOAonID90mXoFLeVJUt6Cze6l7VcXcUytA8HcVMAMYnb w==; X-IronPort-AV: E=McAfee;i="6600,9927,10762"; a="362218766" X-IronPort-AV: E=Sophos;i="6.01,183,1684825200"; d="scan'208";a="362218766" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2023 07:17:31 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10762"; a="965848045" X-IronPort-AV: E=Sophos;i="6.01,183,1684825200"; d="scan'208";a="965848045" Received: from jialinji-mobl4.ccr.corp.intel.com (HELO localhost) ([10.255.30.200]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2023 07:17:27 -0700 Date: Wed, 5 Jul 2023 22:17:42 +0800 From: Yu Zhang To: David Stevens Cc: Sean Christopherson , Marc Zyngier , Michael Ellerman , Peter Xu , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org Subject: Re: [PATCH v7 5/8] KVM: x86/mmu: Don't pass FOLL_GET to __kvm_follow_pfn Message-ID: <20230705141741.xqvjddsoo5qgax63@linux.intel.com> References: <20230704075054.3344915-1-stevensd@google.com> <20230704075054.3344915-6-stevensd@google.com> <20230705101800.ut4c6topn6ylwczs@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230705101800.ut4c6topn6ylwczs@linux.intel.com> User-Agent: NeoMutt/20171215 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > @@ -883,7 +884,7 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, > > */ > > static int FNAME(sync_spte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, int i) > > { > > - bool host_writable; > > + bool host_writable, is_refcounted; > > gpa_t first_pte_gpa; > > u64 *sptep, spte; > > struct kvm_memory_slot *slot; > > @@ -940,10 +941,12 @@ static int FNAME(sync_spte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, int > > sptep = &sp->spt[i]; > > spte = *sptep; > > host_writable = spte & shadow_host_writable_mask; > > + // TODO: is this correct? > > + is_refcounted = spte & SPTE_MMU_PAGE_REFCOUNTED; > > slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); > > make_spte(vcpu, sp, slot, pte_access, gfn, > > spte_to_pfn(spte), spte, true, false, > > - host_writable, &spte); > > + host_writable, is_refcounted, &spte); > > Could we restrict that a non-refcounted page shall not be used as shadow page? Oh, sorry. It's not about shadow page. It's about guest page being mapped as not refcounted. Silly me... B.R. Yu