From nobody Sat Apr 11 21:17:16 2026 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 8F8EDC19F2A for ; Sun, 7 Aug 2022 22:32:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242441AbiHGWcs (ORCPT ); Sun, 7 Aug 2022 18:32:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242290AbiHGWbk (ORCPT ); Sun, 7 Aug 2022 18:31:40 -0400 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BAAA91836E; Sun, 7 Aug 2022 15:18:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1659910732; x=1691446732; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vpSLndbfs6RqeobMkXPOe0+TrlAhD95ZYYobrsGmqRk=; b=gn8LeKaOUkE35m8TWsHu8qzlPVV0wTswctvdWp6KiB5FBonCZs/YOSve TzsKPBauYKqi5JnwL8Qkuj+nQR3S5SPUt3ieqcKVIcdQRWzFLzsYrefDn TmqxTwg0newHLHfYE5q5eRwxhoAzFt3af7ncpWODibqaGVXpKflpIRDMQ AxEVeucARptk38FZBeTxs/Pmmt+SyBH5GmNbsjLSHuNhdkDCVI32nPULm PrY0WYvp+6l2hZ1kpNEGfg+VNEffAqklGl034eljytNXG6aZvKVHih6aB Na/kgwRe7STn/BNB1I+VpdDjy7VJNxkunJUYwv3otA4AKy3dIqC3x+aVy Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10432"; a="270852841" X-IronPort-AV: E=Sophos;i="5.93,221,1654585200"; d="scan'208";a="270852841" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Aug 2022 15:18:52 -0700 X-IronPort-AV: E=Sophos;i="5.93,221,1654585200"; d="scan'208";a="632642339" Received: from ls.sc.intel.com (HELO localhost) ([143.183.96.54]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Aug 2022 15:18:51 -0700 From: isaku.yamahata@intel.com To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com, Paolo Bonzini , erdemaktas@google.com, Sean Christopherson , Sagi Shahar Subject: [RFC PATCH 11/13] KVM: TDP_MMU: Split the large page when zap leaf Date: Sun, 7 Aug 2022 15:18:44 -0700 Message-Id: X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Xiaoyao Li When TDX enabled, a large page cannot be zapped if it contains mixed pages. In this case, it has to split the large page. Signed-off-by: Xiaoyao Li --- arch/x86/kvm/mmu/tdp_mmu.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index faf278e0c740..e5d31242677a 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1033,6 +1033,14 @@ bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_= mmu_page *sp) return true; } =20 + +static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_split(struct kvm *kvm, + struct tdp_iter *iter, + bool shared); + +static int tdp_mmu_split_huge_page(struct kvm *kvm, struct tdp_iter *iter, + struct kvm_mmu_page *sp, bool shared); + /* * If can_yield is true, will release the MMU lock and reschedule if the * scheduler needs the CPU or there is contention on the MMU lock. If this @@ -1075,6 +1083,24 @@ static bool tdp_mmu_zap_leafs(struct kvm *kvm, struc= t kvm_mmu_page *root, !is_last_spte(iter.old_spte, iter.level)) continue; =20 + if (kvm_gfn_shared_mask(kvm) && is_large_pte(iter.old_spte)) { + gfn_t gfn =3D iter.gfn & ~kvm_gfn_shared_mask(kvm); + gfn_t mask =3D KVM_PAGES_PER_HPAGE(iter.level) - 1; + struct kvm_memory_slot *slot; + struct kvm_mmu_page *sp; + + slot =3D gfn_to_memslot(kvm, gfn); + if (kvm_mem_attr_is_mixed(slot, gfn, iter.level) || + (gfn & mask) < start || + end < (gfn & mask) + KVM_PAGES_PER_HPAGE(iter.level)) { + sp =3D tdp_mmu_alloc_sp_for_split(kvm, &iter, false); + WARN_ON(!sp); + + tdp_mmu_split_huge_page(kvm, &iter, sp, false); + continue; + } + } + tdp_mmu_set_spte(kvm, &iter, SHADOW_NONPRESENT_VALUE); flush =3D true; } @@ -1642,8 +1668,6 @@ static struct kvm_mmu_page *tdp_mmu_alloc_sp_for_spli= t(struct kvm *kvm, =20 WARN_ON(kvm_mmu_page_role_is_private(role) !=3D is_private_sptep(iter->sptep)); - /* TODO: Large page isn't supported for private SPTE yet. */ - WARN_ON(kvm_mmu_page_role_is_private(role)); =20 /* * Since we are allocating while under the MMU lock we have to be --=20 2.25.1