lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220221162243.683208-24-pbonzini@redhat.com>
Date:   Mon, 21 Feb 2022 11:22:41 -0500
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:     dmatlack@...gle.com, seanjc@...gle.com
Subject: [PATCH v2 23/25] KVM: x86/mmu: replace direct_map with root_role.direct

direct_map is always equal to the direct field of the root page's role:

- for shadow paging, direct_map is true if CR0.PG=0 and root_role.direct is
copied from cpu_mode.base.direct

- for TDP, it is always true and root_role.direct is also always true

- for shadow EPT, it is always false and root_role.direct is also always
false

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/include/asm/kvm_host.h |  1 -
 arch/x86/kvm/mmu/mmu.c          | 27 ++++++++++++---------------
 arch/x86/kvm/x86.c              | 12 ++++++------
 3 files changed, 18 insertions(+), 22 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ec89b1a488c5..af90d0653139 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -431,7 +431,6 @@ struct kvm_mmu {
 	struct kvm_mmu_root_info root;
 	union kvm_mmu_paging_mode cpu_mode;
 	union kvm_mmu_page_role root_role;
-	bool direct_map;
 	struct kvm_mmu_root_info prev_roots[KVM_MMU_NUM_PREV_ROOTS];
 
 	/*
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 0c88d4206715..8eb2c0373309 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2029,7 +2029,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
 					     int direct,
 					     unsigned int access)
 {
-	bool direct_mmu = vcpu->arch.mmu->direct_map;
+	bool direct_mmu = vcpu->arch.mmu->root_role.direct;
 	union kvm_mmu_page_role role;
 	struct hlist_head *sp_list;
 	unsigned quadrant;
@@ -2131,7 +2131,7 @@ static void shadow_walk_init_using_root(struct kvm_shadow_walk_iterator *iterato
 
 	if (iterator->level >= PT64_ROOT_4LEVEL &&
 	    vcpu->arch.mmu->cpu_mode.base.level < PT64_ROOT_4LEVEL &&
-	    !vcpu->arch.mmu->direct_map)
+	    !vcpu->arch.mmu->root_role.direct)
 		iterator->level = PT32E_ROOT_LEVEL;
 
 	if (iterator->level == PT32E_ROOT_LEVEL) {
@@ -2507,7 +2507,7 @@ static int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
 	gpa_t gpa;
 	int r;
 
-	if (vcpu->arch.mmu->direct_map)
+	if (vcpu->arch.mmu->root_role.direct)
 		return 0;
 
 	gpa = kvm_mmu_gva_to_gpa_read(vcpu, gva, NULL);
@@ -3545,7 +3545,8 @@ static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
 	 * equivalent level in the guest's NPT to shadow.  Allocate the tables
 	 * on demand, as running a 32-bit L1 VMM on 64-bit KVM is very rare.
 	 */
-	if (mmu->direct_map || mmu->cpu_mode.base.level >= PT64_ROOT_4LEVEL ||
+	if (mmu->root_role.direct ||
+	    mmu->cpu_mode.base.level >= PT64_ROOT_4LEVEL ||
 	    mmu->root_role.level < PT64_ROOT_4LEVEL)
 		return 0;
 
@@ -3634,7 +3635,7 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu)
 	int i;
 	struct kvm_mmu_page *sp;
 
-	if (vcpu->arch.mmu->direct_map)
+	if (vcpu->arch.mmu->root_role.direct)
 		return;
 
 	if (!VALID_PAGE(vcpu->arch.mmu->root.hpa))
@@ -3854,7 +3855,7 @@ static bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 
 	arch.token = (vcpu->arch.apf.id++ << 12) | vcpu->vcpu_id;
 	arch.gfn = gfn;
-	arch.direct_map = mmu->direct_map;
+	arch.direct_map = mmu->root_role.direct;
 	arch.cr3 = kvm_mmu_get_guest_pgd(vcpu, mmu);
 
 	return kvm_setup_async_pf(vcpu, cr2_or_gpa,
@@ -4072,7 +4073,6 @@ static void nonpaging_init_context(struct kvm_mmu *context)
 	context->gva_to_gpa = nonpaging_gva_to_gpa;
 	context->sync_page = nonpaging_sync_page;
 	context->invlpg = NULL;
-	context->direct_map = true;
 }
 
 static inline bool is_root_usable(struct kvm_mmu_root_info *root, gpa_t pgd,
@@ -4654,7 +4654,6 @@ static void paging64_init_context(struct kvm_mmu *context)
 	context->gva_to_gpa = paging64_gva_to_gpa;
 	context->sync_page = paging64_sync_page;
 	context->invlpg = paging64_invlpg;
-	context->direct_map = false;
 }
 
 static void paging32_init_context(struct kvm_mmu *context)
@@ -4663,7 +4662,6 @@ static void paging32_init_context(struct kvm_mmu *context)
 	context->gva_to_gpa = paging32_gva_to_gpa;
 	context->sync_page = paging32_sync_page;
 	context->invlpg = paging32_invlpg;
-	context->direct_map = false;
 }
 
 static union kvm_mmu_paging_mode
@@ -4748,7 +4746,6 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu, union kvm_mmu_paging_mode cp
 	context->page_fault = kvm_tdp_page_fault;
 	context->sync_page = nonpaging_sync_page;
 	context->invlpg = NULL;
-	context->direct_map = true;
 	context->get_guest_pgd = kvm_get_guest_cr3;
 	context->get_pdptr = kvm_pdptr_read;
 	context->inject_page_fault = kvm_inject_page_fault;
@@ -4872,7 +4869,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly,
 		context->gva_to_gpa = ept_gva_to_gpa;
 		context->sync_page = ept_sync_page;
 		context->invlpg = ept_invlpg;
-		context->direct_map = false;
+
 		update_permission_bitmask(context, true);
 		context->pkru_mask = 0;
 		reset_rsvds_bits_mask_ept(vcpu, context, execonly, huge_page_level);
@@ -4987,13 +4984,13 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
 {
 	int r;
 
-	r = mmu_topup_memory_caches(vcpu, !vcpu->arch.mmu->direct_map);
+	r = mmu_topup_memory_caches(vcpu, !vcpu->arch.mmu->root_role.direct);
 	if (r)
 		goto out;
 	r = mmu_alloc_special_roots(vcpu);
 	if (r)
 		goto out;
-	if (vcpu->arch.mmu->direct_map)
+	if (vcpu->arch.mmu->root_role.direct)
 		r = mmu_alloc_direct_roots(vcpu);
 	else
 		r = mmu_alloc_shadow_roots(vcpu);
@@ -5197,7 +5194,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
 		       void *insn, int insn_len)
 {
 	int r, emulation_type = EMULTYPE_PF;
-	bool direct = vcpu->arch.mmu->direct_map;
+	bool direct = vcpu->arch.mmu->root_role.direct;
 
 	if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root.hpa)))
 		return RET_PF_RETRY;
@@ -5228,7 +5225,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
 	 * paging in both guests. If true, we simply unprotect the page
 	 * and resume the guest.
 	 */
-	if (vcpu->arch.mmu->direct_map &&
+	if (vcpu->arch.mmu->root_role.direct &&
 	    (error_code & PFERR_NESTED_GUEST_PAGE) == PFERR_NESTED_GUEST_PAGE) {
 		kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(cr2_or_gpa));
 		return 1;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1546a25a9307..53730e81ceb5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8016,7 +8016,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 	    WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF)))
 		return false;
 
-	if (!vcpu->arch.mmu->direct_map) {
+	if (!vcpu->arch.mmu->root_role.direct) {
 		/*
 		 * Write permission should be allowed since only
 		 * write access need to be emulated.
@@ -8049,7 +8049,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 	kvm_release_pfn_clean(pfn);
 
 	/* The instructions are well-emulated on direct mmu. */
-	if (vcpu->arch.mmu->direct_map) {
+	if (vcpu->arch.mmu->root_role.direct) {
 		unsigned int indirect_shadow_pages;
 
 		write_lock(&vcpu->kvm->mmu_lock);
@@ -8117,7 +8117,7 @@ static bool retry_instruction(struct x86_emulate_ctxt *ctxt,
 	vcpu->arch.last_retry_eip = ctxt->eip;
 	vcpu->arch.last_retry_addr = cr2_or_gpa;
 
-	if (!vcpu->arch.mmu->direct_map)
+	if (!vcpu->arch.mmu->root_role.direct)
 		gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2_or_gpa, NULL);
 
 	kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
@@ -8397,7 +8397,7 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
 		ctxt->exception.address = cr2_or_gpa;
 
 		/* With shadow page tables, cr2 contains a GVA or nGPA. */
-		if (vcpu->arch.mmu->direct_map) {
+		if (vcpu->arch.mmu->root_role.direct) {
 			ctxt->gpa_available = true;
 			ctxt->gpa_val = cr2_or_gpa;
 		}
@@ -12198,7 +12198,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
 {
 	int r;
 
-	if ((vcpu->arch.mmu->direct_map != work->arch.direct_map) ||
+	if ((vcpu->arch.mmu->root_role.direct != work->arch.direct_map) ||
 	      work->wakeup_all)
 		return;
 
@@ -12206,7 +12206,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
 	if (unlikely(r))
 		return;
 
-	if (!vcpu->arch.mmu->direct_map &&
+	if (!vcpu->arch.mmu->root_role.direct &&
 	      work->arch.cr3 != kvm_mmu_get_guest_pgd(vcpu, vcpu->arch.mmu))
 		return;
 
-- 
2.31.1


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ