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=-13.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 E7641C433DF for ; Wed, 5 Aug 2020 19:51:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4FFC20842 for ; Wed, 5 Aug 2020 19:51:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="GxS+vZ2k" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729120AbgHETve (ORCPT ); Wed, 5 Aug 2020 15:51:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728212AbgHEQwU (ORCPT ); Wed, 5 Aug 2020 12:52:20 -0400 Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 58109C0A893B; Wed, 5 Aug 2020 07:12:31 -0700 (PDT) Received: by mail-pl1-x644.google.com with SMTP id r4so14687781pls.2; Wed, 05 Aug 2020 07:12:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=ubR+1U/66cwEoUeTJMc9atQb7+ROgmCea2NvMPQs8PQ=; b=GxS+vZ2kVfbNjb07AZMVexUY0voxfkHVoEXsmMZImY7zdHxjqEqIk93rbwZ1Y2upMe iacdMzNeIUNZxaskLbQugw+oEvKagukI3WviguHLiY+BPthHNnn51BVYQtJV5+lnsmpb qUfHuAti9HoDFFnGk1nOlUKdSbj7KlQDPPnRh+JzvyRUgkfh5nlpXho1ilUoNrmVj87d X/jK5c6fFchj/PKd990jxwDPZed3+iBMy6cxPzms6XR3Jwd/NBknzE6y0Fici3z72d7a YYksm3vRqLGxcdeIxog9DquthiKVRs0BpfaaQh0quVFLMjqyLu4+79mfW/dtkvC/h1ny SGqg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=ubR+1U/66cwEoUeTJMc9atQb7+ROgmCea2NvMPQs8PQ=; b=hOGQ9tpfKXXOmTxIgAa9JqGe4/hM9+uXW0hOeUzeVicZdIkAMiiv0H79FqCRaUF/5P qkHadqLrR6RVSSlZ6QUk79c/dCJ9kDomvs0l5lZl2wTQjiGrixoEtX371VAD9ztt8gxx EvK72aix1ufSFNAhzl11LErgbfCKdBaqEMrZpaD6BWfoOnQV+C1pw4OWfHtP5flI8nJm 1xqVFsK4x8mNucQY2OwDvmYEDnx+Dq+Rh3GaJbidLOh6DF0MaZ0CEMv/uOFg/jMXb7yp WcRY0f6nzTlvHBnaF7HvpJjUAGUavV1+sIop7O7l4zLKbfHBmH1n4KP5MUe69N29sbmM hPVA== X-Gm-Message-State: AOAM530CFNlgYWN+LuQpBwX9D/YWvEkZEfNRgrsHB2GOIa+0n8O9czCj 6RpjxEAeEIcoF0AZiRh+28I= X-Google-Smtp-Source: ABdhPJwvn3rF3guqUVD0j8h0EFW39vmETXxaXwHQFfjOtTy0pj72nVixtwJD0JIxQcE/AVhbQg8p1A== X-Received: by 2002:a17:90a:b88b:: with SMTP id o11mr3527448pjr.58.1596636750850; Wed, 05 Aug 2020 07:12:30 -0700 (PDT) Received: from localhost.localdomain ([203.205.141.62]) by smtp.gmail.com with ESMTPSA id l17sm4156287pff.126.2020.08.05.07.12.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Aug 2020 07:12:30 -0700 (PDT) From: Yulei Zhang To: pbonzini@redhat.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, sean.j.christopherson@intel.com, jmattson@google.com, vkuznets@redhat.com, xiaoguangrong.eric@gmail.com, kernellwp@gmail.com, lihaiwei.kernel@gmail.com, Yulei Zhang Subject: [RFC 3/9] Introduce page table remove function for direct build EPT feature Date: Wed, 5 Aug 2020 22:13:20 +0800 Message-Id: <20200805141320.8941-1-yulei.kernel@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yulei Zhang During guest boots up it will modify the memory slots multiple times, so add page table remove function to free pre-pinned memory according to the the memory slot changes. Signed-off-by: Yulei Zhang --- arch/x86/kvm/mmu/mmu.c | 56 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 1609012be67d..539974183653 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -6454,6 +6454,62 @@ int kvm_direct_tdp_populate_page_table(struct kvm *kvm, struct kvm_memory_slot * return 0; } +static int __kvm_remove_spte(struct kvm *kvm, u64 *addr, gfn_t gfn, int level) +{ + int i; + int ret = level; + bool present = false; + kvm_pfn_t pfn; + u64 *sptep = (u64 *)__va((*addr) & PT64_BASE_ADDR_MASK); + unsigned index = SHADOW_PT_INDEX(gfn << PAGE_SHIFT, level); + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + if (is_shadow_present_pte(sptep[i])) { + if (i == index) { + if (!is_last_spte(sptep[i], level)) { + ret = __kvm_remove_spte(kvm, &sptep[i], gfn, level - 1); + if (is_shadow_present_pte(sptep[i])) + return ret; + } else { + pfn = spte_to_pfn(sptep[i]); + mmu_spte_clear_track_bits(&sptep[i]); + kvm_release_pfn_clean(pfn); + if (present) + return ret; + } + } else { + if (i > index) + return ret; + else + present = true; + } + } + } + + if (!present) { + pfn = spte_to_pfn(*addr); + mmu_spte_clear_track_bits(addr); + kvm_release_pfn_clean(pfn); + } + return ret; +} + +void kvm_direct_tdp_remove_page_table(struct kvm *kvm, struct kvm_memory_slot *slot) +{ + gfn_t gfn = slot->base_gfn; + int host_level; + + if (!kvm->arch.global_root_hpa) + return; + + for (gfn = slot->base_gfn; + gfn < slot->base_gfn + slot->npages; + gfn += KVM_PAGES_PER_HPAGE(host_level)) + host_level = __kvm_remove_spte(kvm, &(kvm->arch.global_root_hpa), gfn, PT64_ROOT_4LEVEL); + + kvm_flush_remote_tlbs(kvm); +} + /* * Calculate mmu pages needed for kvm. */ -- 2.17.1