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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2B4AC43217 for ; Mon, 17 Oct 2022 14:53:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EFA586B0074; Mon, 17 Oct 2022 10:53:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E82BD6B0075; Mon, 17 Oct 2022 10:53:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CFC9B6B0078; Mon, 17 Oct 2022 10:53:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id BE1B86B0074 for ; Mon, 17 Oct 2022 10:53:18 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 8FD75140F15 for ; Mon, 17 Oct 2022 14:53:18 +0000 (UTC) X-FDA: 80030734476.11.E61A8B0 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by imf23.hostedemail.com (Postfix) with ESMTP id 9FF60140037 for ; Mon, 17 Oct 2022 14:53:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1666018397; x=1697554397; h=date:from:to:cc:subject:message-id:reply-to:references: mime-version:in-reply-to; bh=I4wfniHW10JfPeprn5rTb+kTvRXkxXZTaEZmmRNpMCk=; b=Cks15SIxzGglhiUY65nLOEvPhj0VSj/p9eGaKppncS57YSvgVzzd7sR7 D8NMZejKag3YiZjVZ0DXDrwg1zyCYpW8mBmUxoyLxJo9+FKwrPDAhzRFS Tsv4cwyfsWuNw71JDc9uzbE213bZzDr+r8jwgQ+vxk/aM7N7aoucJaH7T i30Y7YO1jVZ+td7Ti+eB8ii3faGv59100ifWHvlZZD4PbzsC4ZQBO2zGX mrb0BUhcDuBIeyX1sQcaGUHJQTyUlr1LeqUwsRyxt5ip26kojop9EQCdj sl+P4AHdjz7FLaCaSiTfclCKEKrDbbtvsDlwSNbgVlfchBWhlgeN5+tP+ A==; X-IronPort-AV: E=McAfee;i="6500,9779,10503"; a="367838995" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="367838995" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2022 07:53:15 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10503"; a="691384101" X-IronPort-AV: E=Sophos;i="5.95,191,1661842800"; d="scan'208";a="691384101" Received: from chaop.bj.intel.com (HELO localhost) ([10.240.193.75]) by fmsmga008.fm.intel.com with ESMTP; 17 Oct 2022 07:53:06 -0700 Date: Mon, 17 Oct 2022 22:48:35 +0800 From: Chao Peng To: Sean Christopherson Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-doc@vger.kernel.org, qemu-devel@nongnu.org, Paolo Bonzini , Jonathan Corbet , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , Hugh Dickins , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Shuah Khan , Mike Rapoport , Steven Price , "Maciej S . Szmigiero" , Vlastimil Babka , Vishal Annapurve , Yu Zhang , "Kirill A . Shutemov" , luto@kernel.org, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com, aarcange@redhat.com, ddutile@redhat.com, dhildenb@redhat.com, Quentin Perret , Michael Roth , mhocko@suse.com, Muchun Song , wei.w.wang@intel.com Subject: Re: [PATCH v8 7/8] KVM: Handle page fault for private memory Message-ID: <20221017144835.GA3417432@chaop.bj.intel.com> Reply-To: Chao Peng References: <20220915142913.2213336-1-chao.p.peng@linux.intel.com> <20220915142913.2213336-8-chao.p.peng@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666018398; h=from:from:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=lX8VZgla5Wwn/UQH4Nrn3JPsMLFd75hoLnk+FaZa7Bg=; b=uojRNNy+CjuOlHEmya4Yv0unXv5HaqzGMu61Sml4mtIXjy7HYKsnZTSYb0x/wfHCEr/jhv mxCpAhEXaHUOS9Z4i1YNPJMTTQHsUysJRps1d8mQ9jEAs+wh7be48lZC3Qo3g0aRjIg0w4 iny1QldsHgJSnHND1N6Rr8+gjX7N1yI= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=Cks15SIx; spf=none (imf23.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.31) smtp.mailfrom=chao.p.peng@linux.intel.com; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none) ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666018398; a=rsa-sha256; cv=none; b=R6PcTGAseQKiC/R/idTqwgxT09aMq/LsqpSTCObCLkOtSeBmEPmSDsZk7hjBLLioby6daF m0w7yOb8O5JqjTg+2vbEBMN2uzdqPS0jOBOvfBlBWkuT8/JWnQ7N4jFD5XJFcrzJo/QnYN DdbaI+3GiDVw+yubaQfAS0MBUSzx6OY= X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 9FF60140037 X-Rspam-User: Authentication-Results: imf23.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=Cks15SIx; spf=none (imf23.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.31) smtp.mailfrom=chao.p.peng@linux.intel.com; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none) X-Stat-Signature: rxm9foeig7388fgq8qxk68quqyz5p38c X-HE-Tag: 1666018397-522065 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Oct 14, 2022 at 06:57:20PM +0000, Sean Christopherson wrote: > On Thu, Sep 15, 2022, Chao Peng wrote: > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > > index a0f198cede3d..81ab20003824 100644 > > --- a/arch/x86/kvm/mmu/mmu.c > > +++ b/arch/x86/kvm/mmu/mmu.c > > @@ -3028,6 +3028,9 @@ int kvm_mmu_max_mapping_level(struct kvm *kvm, > > break; > > } > > > > + if (kvm_mem_is_private(kvm, gfn)) > > Rather than reload the Xarray info, which is unnecessary overhead, pass in > @is_private. The caller must hold mmu_lock, i.e. invalidations from > private<->shared conversions will be stalled and will zap the new SPTE if the > state is changed. Make sense. TDX/SEV should be easy to query that. Chao > > E.g. > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index d68944f07b4b..44eea47697d8 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c > @@ -3072,8 +3072,8 @@ void kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault > * Enforce the iTLB multihit workaround after capturing the requested > * level, which will be used to do precise, accurate accounting. > */ > - fault->req_level = kvm_mmu_max_mapping_level(vcpu->kvm, slot, > - fault->gfn, fault->max_level); > + fault->req_level = kvm_mmu_max_mapping_level(vcpu->kvm, slot, fault->gfn, > + fault->max_level, fault->is_private); > if (fault->req_level == PG_LEVEL_4K || fault->huge_page_disallowed) > return; > > @@ -6460,7 +6460,7 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm, > */ > if (sp->role.direct && > sp->role.level < kvm_mmu_max_mapping_level(kvm, slot, sp->gfn, > - PG_LEVEL_NUM)) { > + PG_LEVEL_NUM, false)) { > kvm_zap_one_rmap_spte(kvm, rmap_head, sptep); > > if (kvm_available_flush_tlb_with_range()) > diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h > index 7670c13ce251..9acdf72537ce 100644 > --- a/arch/x86/kvm/mmu/spte.h > +++ b/arch/x86/kvm/mmu/spte.h > @@ -315,6 +315,12 @@ static inline bool is_dirty_spte(u64 spte) > return dirty_mask ? spte & dirty_mask : spte & PT_WRITABLE_MASK; > } > > +static inline bool is_private_spte(u64 spte) > +{ > + /* FIXME: Query C-bit/S-bit for SEV/TDX. */ > + return false; > +} > + > static inline u64 get_rsvd_bits(struct rsvd_bits_validate *rsvd_check, u64 pte, > int level) > { > diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c > index 672f0432d777..69ba00157e90 100644 > --- a/arch/x86/kvm/mmu/tdp_mmu.c > +++ b/arch/x86/kvm/mmu/tdp_mmu.c > @@ -1767,8 +1767,9 @@ static void zap_collapsible_spte_range(struct kvm *kvm, > if (iter.gfn < start || iter.gfn >= end) > continue; > > - max_mapping_level = kvm_mmu_max_mapping_level(kvm, slot, > - iter.gfn, PG_LEVEL_NUM); > + max_mapping_level = kvm_mmu_max_mapping_level(kvm, slot, iter.gfn, > + PG_LEVEL_NUM, > + is_private_spte(iter.old_spte)); > if (max_mapping_level < iter.level) > continue; >