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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E3D3EC5B570 for ; Mon, 10 Aug 2026 20:52:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=2lUDCeHA9FlDMq90kbiv10fUnpuw5bEWKTS/5Opyf00=; b=Y9jsjVkpqvq6oO3AK1mBZd4Vbi hQjqX0tOZWuidEImWydXf/Z5EnjRI4oO2unVFSMYqBrLdLn9BGBCgxiDwnR4f2cCn6oPgO9benyMJ /z3PFVkuCwWunWFwtMN3VCNfz64i7VuX9tLc4PJ2jx9PtP+7U+Ul7VkC4CXnk9rtSHb2gfUComDfQ RgEPk8lGgMu5unDiN/4BWhrmAsykKz2wp3a6Vfpw10XJAkgRWJSBpgyRAuregqnqJ8Nij2CQ4j7DS CdEM3uM0cuN+e4Bb5qJc1DmVZVbU1UrH8kUoX9DbK5o0zEdjtvBojvt8rwoCCZleOHbq9MK2Hukqw yXwNqROw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wtWyX-0000000Cqym-2R62; Mon, 10 Aug 2026 20:52:01 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wtWyT-0000000Cqvk-2KLH for linux-arm-kernel@lists.infradead.org; Mon, 10 Aug 2026 20:51:58 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C44791516; Mon, 10 Aug 2026 13:51:51 -0700 (PDT) Received: from workstation-e142269.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D2BB83F673; Mon, 10 Aug 2026 13:51:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1786395115; bh=hN26P/A7fPLce60cNx8etfOGz+xdHCZDDJNeNaHZn5U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KbEWoXiadmbBfT9ixd2GAFqz9FXrmRXiuqzsMnN8bAxCWDoVW6zt/ngneh3o/bRl/ iiU2+MKQwB7mp2sWun5HX2a8rX4ayUV2qiXc5tjRvFsyMsbsHBT6KPnWdl17LJPWKx 5ZcQ0YdIG1LXmBJVJS1W66ODjqJ+8QjTwdqrxUVs= From: Wei-Lin Chang To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Cc: Marc Zyngier , Oliver Upton , Fuad Tabba , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Lorenzo Stoakes , Itaru Kitayama , Wei-Lin Chang Subject: [PATCH v5 3/6] KVM: arm64: nv: Track guest stage-2 mapping creation Date: Mon, 10 Aug 2026 21:50:35 +0100 Message-ID: <20260810205038.118843-4-weilin.chang@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260810205038.118843-1-weilin.chang@arm.com> References: <20260810205038.118843-1-weilin.chang@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260810_135157_681740_B915A29B X-CRM114-Status: GOOD ( 16.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org During shadow stage-2 faults, in addition to creating mappings in the shadow page tables, also allocate kvm_guest_s2_mapping objects, record the mapping ranges, and insert them into the canonical and nested mmu's guest_s2_mappings tree. Note that because we allow parallel faulting, the interval trees could store mappings that are not live in the shadow page tables. Storing a superset of the live mappings is fine because we will only over-unmap when we use this information later to do the targeted MMU notifier unmap. Signed-off-by: Wei-Lin Chang --- arch/arm64/include/asm/kvm_nested.h | 3 +++ arch/arm64/kvm/mmu.c | 29 +++++++++++++++++++++++++++++ arch/arm64/kvm/nested.c | 25 +++++++++++++++++++++++++ 3 files changed, 57 insertions(+) diff --git a/arch/arm64/include/asm/kvm_nested.h b/arch/arm64/include/asm/kvm_nested.h index 012d711034d1..560b78b3f5ff 100644 --- a/arch/arm64/include/asm/kvm_nested.h +++ b/arch/arm64/include/asm/kvm_nested.h @@ -77,6 +77,9 @@ extern void kvm_s2_mmu_iterate_by_vmid(struct kvm *kvm, u16 vmid, const union tlbi_info *info, void (*)(struct kvm_s2_mmu *, const union tlbi_info *)); +extern void kvm_record_guest_s2_mapping(struct kvm_s2_mmu *mmu, gpa_t canonical_ipa, + gpa_t nested_ipa, size_t map_size, + struct kvm_guest_s2_mapping *mapping); extern void kvm_vcpu_load_hw_mmu(struct kvm_vcpu *vcpu); extern void kvm_vcpu_put_hw_mmu(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 59b4f583240e..cea968921041 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1642,6 +1642,7 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) enum kvm_pgtable_walk_flags flags = KVM_PGTABLE_WALK_SHARED; enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R; struct kvm_pgtable *pgt = s2fd->vcpu->arch.hw_mmu->pgt; + struct kvm_guest_s2_mapping *mapping = NULL; unsigned long mmu_seq; struct page *page; struct kvm *kvm = s2fd->vcpu->kvm; @@ -1655,6 +1656,11 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) ret = topup_mmu_memcache(s2fd->vcpu, memcache); if (ret) return ret; + if (kvm_is_nested_s2_mmu(kvm, pgt->mmu)) { + mapping = kmalloc_obj(struct kvm_guest_s2_mapping, GFP_KERNEL_ACCOUNT); + if (!mapping) + return -ENOMEM; + } } if (s2fd->nested) @@ -1675,6 +1681,7 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) if (ret) { kvm_prepare_memory_fault_exit(s2fd->vcpu, s2fd->fault_ipa, PAGE_SIZE, write_fault, exec_fault, false); + kfree(mapping); return ret; } @@ -1708,11 +1715,17 @@ static int gmem_abort(const struct kvm_s2_fault_desc *s2fd) ret = KVM_PGT_FN(kvm_pgtable_stage2_map)(pgt, s2fd->fault_ipa, PAGE_SIZE, __pfn_to_phys(pfn), prot, memcache, flags); + if (!ret && kvm_is_nested_s2_mmu(kvm, pgt->mmu)) { + kvm_record_guest_s2_mapping(pgt->mmu, gfn << PAGE_SHIFT, + s2fd->fault_ipa, PAGE_SIZE, mapping); + mapping = NULL; + } } out_unlock: kvm_release_faultin_page(kvm, page, !!ret, prot & KVM_PGTABLE_PROT_W); kvm_fault_unlock(kvm); + kfree(mapping); if ((prot & KVM_PGTABLE_PROT_W) && !ret) mark_page_dirty_in_slot(kvm, s2fd->memslot, gfn); @@ -2049,6 +2062,7 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, void *memcache) { enum kvm_pgtable_walk_flags flags = KVM_PGTABLE_WALK_SHARED; + struct kvm_guest_s2_mapping *mapping = NULL; bool writable = prot & KVM_PGTABLE_PROT_W; struct kvm *kvm = s2fd->vcpu->kvm; phys_addr_t canonical_ipa; @@ -2059,6 +2073,15 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, gfn_t gfn; int ret; + if (kvm_is_nested_s2_mmu(kvm, s2fd->vcpu->arch.hw_mmu)) { + mapping = kmalloc_obj(struct kvm_guest_s2_mapping, + GFP_KERNEL_ACCOUNT); + if (!mapping) { + kvm_release_page_unused(s2vi->page); + return -ENOMEM; + } + } + kvm_fault_lock(kvm); pgt = s2fd->vcpu->arch.hw_mmu->pgt; ret = -EAGAIN; @@ -2112,11 +2135,17 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, ret = KVM_PGT_FN(kvm_pgtable_stage2_map)(pgt, gfn_to_gpa(gfn), mapping_size, __pfn_to_phys(pfn), prot, memcache, flags); + if (!ret && kvm_is_nested_s2_mmu(kvm, pgt->mmu)) { + kvm_record_guest_s2_mapping(pgt->mmu, canonical_ipa, + gfn_to_gpa(gfn), mapping_size, mapping); + mapping = NULL; + } } out_unlock: kvm_release_faultin_page(kvm, s2vi->page, !!ret, writable); kvm_fault_unlock(kvm); + kfree(mapping); /* * Mark the page dirty only if the fault is handled successfully, diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c index 744aacba61ae..646b628bba17 100644 --- a/arch/arm64/kvm/nested.c +++ b/arch/arm64/kvm/nested.c @@ -5,6 +5,7 @@ */ #include +#include #include #include @@ -852,6 +853,30 @@ static struct kvm_s2_mmu *get_s2_mmu_nested(struct kvm_vcpu *vcpu) return s2_mmu; } +void kvm_record_guest_s2_mapping(struct kvm_s2_mmu *mmu, gpa_t canonical_ipa, + gpa_t nested_ipa, size_t map_size, + struct kvm_guest_s2_mapping *mapping) +{ + struct kvm *kvm = kvm_s2_mmu_to_kvm(mmu); + + lockdep_assert_held_read(&kvm->mmu_lock); + + if (WARN_ON(!IS_ALIGNED(canonical_ipa, map_size))) + canonical_ipa = ALIGN_DOWN(canonical_ipa, map_size); + + mapping->canonical.start = canonical_ipa; + mapping->canonical.last = canonical_ipa + map_size - 1; + + mapping->nested.start = nested_ipa; + mapping->nested.last = nested_ipa + map_size - 1; + + mapping->nested_mmu = mmu; + + guard(spinlock)(&kvm->arch.guest_s2_tracking_lock); + interval_tree_insert(&mapping->nested, &mmu->guest_s2_mappings); + interval_tree_insert(&mapping->canonical, &kvm->arch.mmu.guest_s2_mappings); +} + void kvm_init_nested_s2_mmu(struct kvm_s2_mmu *mmu) { /* CnP being set denotes an invalid entry */ -- 2.43.0