From nobody Wed Sep 17 06:28:22 2025 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 4F378C4167B for ; Fri, 23 Dec 2022 00:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235931AbiLWA7G (ORCPT ); Thu, 22 Dec 2022 19:59:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230298AbiLWA63 (ORCPT ); Thu, 22 Dec 2022 19:58:29 -0500 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 632A4220D3 for ; Thu, 22 Dec 2022 16:58:02 -0800 (PST) Received: by mail-pg1-x549.google.com with SMTP id f132-20020a636a8a000000b00473d0b600ebso1900253pgc.14 for ; Thu, 22 Dec 2022 16:58:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=ACcf4TIOY/KNCxT8YXaOwMosCx8LQofQdn0euCiCY4M=; b=TMBTtSKif9JQYrBRgC2Kk26Arhd33oSJssQxGXX/l24pjOtYOl3FvdMwZWJ1gMi8be fxmbPb0zXMsVCi1OjlfQel7xq87Va6mq6g/Ca3vzmLvdxVTKlW+1Q5rwQmDHpa7RT1bW 1UfbKAXIuJxp0UmFpoguv7JwOpet+rHaqILtSPjCBepdHWNxYgrzerCuDKGQ78gVYADM K3tr43AkqFOOIuSyw/7t7XKS2KzvT+E6FucHlxZOO89VrQsP8riSCpTQBRNvLE43KMjj MAMf3oEGVz8uxC39pSO9satkIJA10i4iFcEgNSKCfejQPAsa5QzyABTCtrSsCnD+cbDL x8qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=ACcf4TIOY/KNCxT8YXaOwMosCx8LQofQdn0euCiCY4M=; b=frV/BcveQiHintlm5op9jekrOmok5DsXouYoeDyLLgusqML4nhdS949LYvGadWiLWt bLwdK2M6HKipzx2tOanFqfXSl8vlHnRy0oRpP+oSBldTLRa3uqd5LHpoGzwQv/wrFPaY KiynyL3aK8Ld9g3KlCXtYZPqkdv1U6952RYEuEEFhkT/zWk7anvLpEzup3CO3ZMlL52F bQ28cTjA1n1qIJx8ScjNvwNvL4w1s6ofB7j73mRkYC0utSrOd3Qq49Wyz1N7c224OUMi 5Q2357BKmunIl2S5ThmSCn9qwygrnFKpwiGQBSVC2iQrp/FvHro+b1Xg+QC9dSwKOPnd zKGQ== X-Gm-Message-State: AFqh2kpFZcpfjCsZMouq0r9nqQ0l0jciRIB2+pY8jen28ADniWWoMARL RNPL4I+wjfr6xteW9+Uu2N4zPQ8HOAg= X-Google-Smtp-Source: AMrXdXuqqyTgcQHilI53SefEG/5sBcIEwh5xs70zEETtCu7A3Q44yDAHVNGxCdXtPPvHf1LR8O/lpRt7G1I= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:902:d4ca:b0:188:a51c:b570 with SMTP id o10-20020a170902d4ca00b00188a51cb570mr461459plg.7.1671757081979; Thu, 22 Dec 2022 16:58:01 -0800 (PST) Reply-To: Sean Christopherson Date: Fri, 23 Dec 2022 00:57:22 +0000 In-Reply-To: <20221223005739.1295925-1-seanjc@google.com> Mime-Version: 1.0 References: <20221223005739.1295925-1-seanjc@google.com> X-Mailer: git-send-email 2.39.0.314.g84b9a713c41-goog Message-ID: <20221223005739.1295925-11-seanjc@google.com> Subject: [PATCH 10/27] KVM: x86/mmu: Don't rely on page-track mechanism to flush on memslot change From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini , Zhenyu Wang , Zhi Wang Cc: kvm@vger.kernel.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, Yan Zhao , Ben Gardon Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Call kvm_mmu_zap_all_fast() directly when flushing a memslot instead of bounding through the page-track mechanism. KVM (unfortunately) needs to zap and flush all page tables on memslot DELETE/MOVE irrespective of whether KVM is shadowing guest page tables. This will allow changing KVM to register a page-track notifier on the first shadow root allocation, and will also allow deleting the misguided kvm_page_track_flush_slot() hook itself once KVM-GT also moves to a different method for reacting to memslot changes. No functional change intended. Cc: Yan Zhao Signed-off-by: Sean Christopherson Link: https://lore.kernel.org/r/20221110014821.1548347-2-seanjc@google.com --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu/mmu.c | 10 +--------- arch/x86/kvm/x86.c | 2 ++ 3 files changed, 4 insertions(+), 9 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_hos= t.h index aa4eb8cfcd7e..fcb042f971ee 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1798,6 +1798,7 @@ void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm, void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm, const struct kvm_memory_slot *memslot); void kvm_mmu_zap_all(struct kvm *kvm); +void kvm_mmu_zap_all_fast(struct kvm *kvm); void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm, u64 gen); void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned long kvm_nr_mmu_pa= ges); =20 diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index ca7428b68eba..8c3a453554ed 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -6009,7 +6009,7 @@ static void kvm_zap_obsolete_pages(struct kvm *kvm) * not use any resource of the being-deleted slot or all slots * after calling the function. */ -static void kvm_mmu_zap_all_fast(struct kvm *kvm) +void kvm_mmu_zap_all_fast(struct kvm *kvm) { lockdep_assert_held(&kvm->slots_lock); =20 @@ -6065,13 +6065,6 @@ static bool kvm_has_zapped_obsolete_pages(struct kvm= *kvm) return unlikely(!list_empty_careful(&kvm->arch.zapped_obsolete_pages)); } =20 -static void kvm_mmu_invalidate_zap_pages_in_memslot(struct kvm *kvm, - struct kvm_memory_slot *slot, - struct kvm_page_track_notifier_node *node) -{ - kvm_mmu_zap_all_fast(kvm); -} - int kvm_mmu_init_vm(struct kvm *kvm) { struct kvm_page_track_notifier_node *node =3D &kvm->arch.mmu_sp_tracker; @@ -6089,7 +6082,6 @@ int kvm_mmu_init_vm(struct kvm *kvm) } =20 node->track_write =3D kvm_mmu_pte_write; - node->track_flush_slot =3D kvm_mmu_invalidate_zap_pages_in_memslot; kvm_page_track_register_notifier(kvm, node); =20 kvm->arch.split_page_header_cache.kmem_cache =3D mmu_page_header_cache; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 312aea1854ae..af0d83e33bc4 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -12599,6 +12599,8 @@ void kvm_arch_flush_shadow_all(struct kvm *kvm) void kvm_arch_flush_shadow_memslot(struct kvm *kvm, struct kvm_memory_slot *slot) { + kvm_mmu_zap_all_fast(kvm); + kvm_page_track_flush_slot(kvm, slot); } =20 --=20 2.39.0.314.g84b9a713c41-goog