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 C3138C433FE for ; Thu, 17 Nov 2022 19:31:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239737AbiKQTbd (ORCPT ); Thu, 17 Nov 2022 14:31:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234614AbiKQTbb (ORCPT ); Thu, 17 Nov 2022 14:31:31 -0500 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFF246D4B5; Thu, 17 Nov 2022 11:31:29 -0800 (PST) Received: by mail-pj1-x102f.google.com with SMTP id h14so2531910pjv.4; Thu, 17 Nov 2022 11:31:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=WiuxoynRLz+oGeIJ5rNZguwfh42cRexnDNgABpAnrbw=; b=PJeHgBlScQNvwpsB8VT37+K2TGOelG8LHVzzRuMeJyeMCV/S9FqNeSVwMQveoF0ML4 u2Scd+LtFRYOkDMrjDA1HOGQrhYSWigFlybH9405+JFSSyGvezGyH5M9Yr49JBVh/MTY IyYsvkK8cVOKooUix+vei4DlcNQMx+9Pvx+FnX8zXe1LadV2SbDvzuK3mnZbMYpczq0v PIC2e1xlZCEnIl6JT6NqkotFq+59M7yvObvtpGtblwIBDsVoUlhIQhVug0KcZPWnN0oP OihVkPuVmQCWFI17lfGT+BezGi73W9l/IJejQyY10EOCJtRPMwxLEeVesdBhu2DPcVXt zviA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=WiuxoynRLz+oGeIJ5rNZguwfh42cRexnDNgABpAnrbw=; b=AexlF0CMMp2UCFBgGuOd0V0S96J5NALyFkNpMb05u5L7fFoRA3mH7Rj9l4G4YjXrAI XQOHK9cZ5b9edEIp6bGEYi/gpRoeHmgYvtzR3rHTnvR7EVHshFWcA57vkF5Z5d/vAspD VWVPpcRUvJLgW56uL0VrfV3GRqVgkem/NHXubBXXVHiY7enc1g6tzhP5AUWFWZ5+GV6Z AT5cHt2PWm2a/pxHjGczClxnma0NrnKLAZeMvVO0iZMOd7Qcm+HsOOUp1Js0jGM/tLT9 izt1uZKnBF9//DnXasQjq9g+6+aDreYgjkrfCRrDBbz9PJ+Xo9vBDKhY1Fp9qCF2bgh3 vxQA== X-Gm-Message-State: ANoB5plzaONFdolY8EoY+GXHrslV8ffFW5t7mDtoCS5Yhjq3jFbFLzsZ 84Xjhz9tzW+j/TDkn615JQA= X-Google-Smtp-Source: AA0mqf5Wm5P2UM7qzuJWksEsRxlb1kn2Q/c2TQSh8oDstt7T5T8nA8qsxzBctPj/g5aU5NmMxp3hXg== X-Received: by 2002:a17:903:228c:b0:186:8930:20e6 with SMTP id b12-20020a170903228c00b00186893020e6mr4203389plh.64.1668713489442; Thu, 17 Nov 2022 11:31:29 -0800 (PST) Received: from localhost ([192.55.54.55]) by smtp.gmail.com with ESMTPSA id s2-20020a170902a50200b00187022627d7sm1788648plq.36.2022.11.17.11.31.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Nov 2022 11:31:29 -0800 (PST) Date: Thu, 17 Nov 2022 11:31:27 -0800 From: Isaku Yamahata To: "Huang, Kai" Cc: "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Yamahata, Isaku" , "pbonzini@redhat.com" , "Shahar, Sagi" , "Aktas, Erdem" , "isaku.yamahata@gmail.com" , "dmatlack@google.com" , "Christopherson,, Sean" Subject: Re: [PATCH v10 049/108] KVM: x86/tdp_mmu: Support TDX private mapping for TDP MMU Message-ID: <20221117193127.GN2350331@ls.amr.corp.intel.com> References: <9d5595dfe1b5ab77bcb5650bc4d940dd977b0a32.1667110240.git.isaku.yamahata@intel.com> <26a3508e4f57f6104abecd90192f12375fe04ecc.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <26a3508e4f57f6104abecd90192f12375fe04ecc.camel@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 16, 2022 at 11:58:46AM +0000, "Huang, Kai" wrote: > > > > > +static inline int kvm_alloc_private_spt_for_split(struct kvm_mmu_page *sp, gfp_t gfp) > > +{ > > + gfp &= ~__GFP_ZERO; > > + sp->private_spt = (void *)__get_free_page(gfp); > > + if (!sp->private_spt) > > + return -ENOMEM; > > + return 0; > > +} > > + > > > [...] > > > @@ -1238,6 +1408,12 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) > > is_large_pte(iter.old_spte)) { > > if (tdp_mmu_zap_spte_atomic(vcpu->kvm, &iter)) > > break; > > + /* > > + * TODO: large page support. > > + * Doesn't support large page for TDX now > > + */ > > + KVM_BUG_ON(is_private_sptep(iter.sptep), vcpu->kvm); > > + > > > > So large page is not supported for private page, ... > > > /* > > * The iter must explicitly re-read the spte here > > @@ -1480,6 +1656,12 @@ static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp, union kvm_mm > > > > sp->role = role; > > sp->spt = (void *)__get_free_page(gfp); > > + if (kvm_mmu_page_role_is_private(role)) { > > + if (kvm_alloc_private_spt_for_split(sp, gfp)) { > > + free_page((unsigned long)sp->spt); > > + sp->spt = NULL; > > + } > > + } > > ... then I don't think eager splitting could happen for private mapping? > > If so, should we just KVM_BUG_ON() if role is private? Right, will remove this part from this patch series and move it to large page support series. -- Isaku Yamahata