1 files changed, 171 insertions, 392 deletions

diff --git a/linux/x86/paging_tmpl.h b/linux/x86/paging_tmpl.h
index 6bccc24..81eab9a 100644
--- a/linux/x86/paging_tmpl.h
+++ b/linux/x86/paging_tmpl.h
@@ -7,7 +7,6 @@
  * MMU support
  *
  * Copyright (C) 2006 Qumranet, Inc.
- * Copyright 2010 Red Hat, Inc. and/or its affiliates.
  *
  * Authors:
  *   Yaniv Kamay  <yaniv@qumranet.com>
@@ -67,12 +66,11 @@ struct guest_walker {
 	int level;
 	gfn_t table_gfn[PT_MAX_FULL_LEVELS];
 	pt_element_t ptes[PT_MAX_FULL_LEVELS];
-	pt_element_t prefetch_ptes[PTE_PREFETCH_NUM];
 	gpa_t pte_gpa[PT_MAX_FULL_LEVELS];
 	unsigned pt_access;
 	unsigned pte_access;
 	gfn_t gfn;
-	struct x86_exception fault;
+	u32 error_code;
 };
 
 static gfn_t gpte_to_gfn_lvl(pt_element_t gpte, int lvl)
@@ -105,7 +103,7 @@ static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte)
 
 	access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK;
 #if PTTYPE == 64
-	if (vcpu->arch.mmu.nx)
+	if (is_nx(vcpu))
 		access &= ~(gpte >> PT64_NX_SHIFT);
 #endif
 	return access;
@@ -114,42 +112,32 @@ static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte)
 /*
  * Fetch a guest pte for a guest virtual address
  */
-static int FNAME(walk_addr_generic)(struct guest_walker *walker,
-				    struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-				    gva_t addr, u32 access)
+static int FNAME(walk_addr)(struct guest_walker *walker,
+			    struct kvm_vcpu *vcpu, gva_t addr,
+			    int write_fault, int user_fault, int fetch_fault)
 {
 	pt_element_t pte;
 	gfn_t table_gfn;
-	unsigned index, pt_access, uninitialized_var(pte_access);
+	unsigned index, pt_access, pte_access;
 	gpa_t pte_gpa;
-	bool eperm, present, rsvd_fault;
-	int offset, write_fault, user_fault, fetch_fault;
-
-	write_fault = access & PFERR_WRITE_MASK;
-	user_fault = access & PFERR_USER_MASK;
-	fetch_fault = access & PFERR_FETCH_MASK;
+	int rsvd_fault = 0;
 
 	trace_kvm_mmu_pagetable_walk(addr, write_fault, user_fault,
 				     fetch_fault);
 walk:
-	present = true;
-	eperm = rsvd_fault = false;
-	walker->level = mmu->root_level;
-	pte           = mmu->get_cr3(vcpu);
-
+	walker->level = vcpu->arch.mmu.root_level;
+	pte = vcpu->arch.cr3;
 #if PTTYPE == 64
-	if (walker->level == PT32E_ROOT_LEVEL) {
-		pte = kvm_pdptr_read_mmu(vcpu, mmu, (addr >> 30) & 3);
+	if (!is_long_mode(vcpu)) {
+		pte = kvm_pdptr_read(vcpu, (addr >> 30) & 3);
 		trace_kvm_mmu_paging_element(pte, walker->level);
-		if (!is_present_gpte(pte)) {
-			present = false;
-			goto error;
-		}
+		if (!is_present_gpte(pte))
+			goto not_present;
 		--walker->level;
 	}
 #endif
 	ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) ||
-	       (mmu->get_cr3(vcpu) & CR3_NONPAE_RESERVED_BITS) == 0);
+	       (vcpu->arch.cr3 & CR3_NONPAE_RESERVED_BITS) == 0);
 
 	pt_access = ACC_ALL;
 
@@ -157,49 +145,42 @@ walk:
 		index = PT_INDEX(addr, walker->level);
 
 		table_gfn = gpte_to_gfn(pte);
-		offset    = index * sizeof(pt_element_t);
-		pte_gpa   = gfn_to_gpa(table_gfn) + offset;
+		pte_gpa = gfn_to_gpa(table_gfn);
+		pte_gpa += index * sizeof(pt_element_t);
 		walker->table_gfn[walker->level - 1] = table_gfn;
 		walker->pte_gpa[walker->level - 1] = pte_gpa;
 
-		if (kvm_read_guest_page_mmu(vcpu, mmu, table_gfn, &pte,
-					    offset, sizeof(pte),
-					    PFERR_USER_MASK|PFERR_WRITE_MASK)) {
-			present = false;
-			break;
-		}
+		if (kvm_read_guest(vcpu->kvm, pte_gpa, &pte, sizeof(pte)))
+			goto not_present;
 
 		trace_kvm_mmu_paging_element(pte, walker->level);
 
-		if (!is_present_gpte(pte)) {
-			present = false;
-			break;
-		}
+		if (!is_present_gpte(pte))
+			goto not_present;
 
-		if (is_rsvd_bits_set(&vcpu->arch.mmu, pte, walker->level)) {
-			rsvd_fault = true;
-			break;
-		}
+		rsvd_fault = is_rsvd_bits_set(vcpu, pte, walker->level);
+		if (rsvd_fault)
+			goto access_error;
 
 		if (write_fault && !is_writable_pte(pte))
 			if (user_fault || is_write_protection(vcpu))
-				eperm = true;
+				goto access_error;
 
 		if (user_fault && !(pte & PT_USER_MASK))
-			eperm = true;
+			goto access_error;
 
 #if PTTYPE == 64
-		if (fetch_fault && (pte & PT64_NX_MASK))
-			eperm = true;
+		if (fetch_fault && is_nx(vcpu) && (pte & PT64_NX_MASK))
+			goto access_error;
 #endif
 
-		if (!eperm && !rsvd_fault && !(pte & PT_ACCESSED_MASK)) {
+		if (!(pte & PT_ACCESSED_MASK)) {
 			trace_kvm_mmu_set_accessed_bit(table_gfn, index,
 						       sizeof(pte));
+			mark_page_dirty(vcpu->kvm, table_gfn);
 			if (FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn,
 			    index, pte, pte|PT_ACCESSED_MASK))
 				goto walk;
-			mark_page_dirty(vcpu->kvm, table_gfn);
 			pte |= PT_ACCESSED_MASK;
 		}
 
@@ -209,32 +190,21 @@ walk:
 
 		if ((walker->level == PT_PAGE_TABLE_LEVEL) ||
 		    ((walker->level == PT_DIRECTORY_LEVEL) &&
-				is_large_pte(pte) &&
+				(pte & PT_PAGE_SIZE_MASK)  &&
 				(PTTYPE == 64 || is_pse(vcpu))) ||
 		    ((walker->level == PT_PDPE_LEVEL) &&
-				is_large_pte(pte) &&
-				mmu->root_level == PT64_ROOT_LEVEL)) {
+				(pte & PT_PAGE_SIZE_MASK)  &&
+				is_long_mode(vcpu))) {
 			int lvl = walker->level;
-			gpa_t real_gpa;
-			gfn_t gfn;
-			u32 ac;
 
-			gfn = gpte_to_gfn_lvl(pte, lvl);
-			gfn += (addr & PT_LVL_OFFSET_MASK(lvl)) >> PAGE_SHIFT;
+			walker->gfn = gpte_to_gfn_lvl(pte, lvl);
+			walker->gfn += (addr & PT_LVL_OFFSET_MASK(lvl))
+					>> PAGE_SHIFT;
 
 			if (PTTYPE == 32 &&
 			    walker->level == PT_DIRECTORY_LEVEL &&
 			    is_cpuid_PSE36())
-				gfn += pse36_gfn_delta(pte);
-
-			ac = write_fault | fetch_fault | user_fault;
-
-			real_gpa = mmu->translate_gpa(vcpu, gfn_to_gpa(gfn),
-						      ac);
-			if (real_gpa == UNMAPPED_GVA)
-				return 0;
-
-			walker->gfn = real_gpa >> PAGE_SHIFT;
+				walker->gfn += pse36_gfn_delta(pte);
 
 			break;
 		}
@@ -243,18 +213,15 @@ walk:
 		--walker->level;
 	}
 
-	if (!present || eperm || rsvd_fault)
-		goto error;
-
 	if (write_fault && !is_dirty_gpte(pte)) {
 		bool ret;
 
 		trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte));
+		mark_page_dirty(vcpu->kvm, table_gfn);
 		ret = FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, index, pte,
 			    pte|PT_DIRTY_MASK);
 		if (ret)
 			goto walk;
-		mark_page_dirty(vcpu->kvm, table_gfn);
 		pte |= PT_DIRTY_MASK;
 		walker->ptes[walker->level - 1] = pte;
 	}
@@ -262,71 +229,30 @@ walk:
 	walker->pt_access = pt_access;
 	walker->pte_access = pte_access;
 	pgprintk("%s: pte %llx pte_access %x pt_access %x\n",
-		 __func__, (u64)pte, pte_access, pt_access);
+		 __func__, (u64)pte, pt_access, pte_access);
 	return 1;
 
-error:
-	walker->fault.vector = PF_VECTOR;
-	walker->fault.error_code_valid = true;
-	walker->fault.error_code = 0;
-	if (present)
-		walker->fault.error_code |= PFERR_PRESENT_MASK;
+not_present:
+	walker->error_code = 0;
+	goto err;
 
-	walker->fault.error_code |= write_fault | user_fault;
+access_error:
+	walker->error_code = PFERR_PRESENT_MASK;
 
-	if (fetch_fault && mmu->nx)
-		walker->fault.error_code |= PFERR_FETCH_MASK;
+err:
+	if (write_fault)
+		walker->error_code |= PFERR_WRITE_MASK;
+	if (user_fault)
+		walker->error_code |= PFERR_USER_MASK;
+	if (fetch_fault)
+		walker->error_code |= PFERR_FETCH_MASK;
 	if (rsvd_fault)
-		walker->fault.error_code |= PFERR_RSVD_MASK;
-
-	walker->fault.address = addr;
-	walker->fault.nested_page_fault = mmu != vcpu->arch.walk_mmu;
-
-	trace_kvm_mmu_walker_error(walker->fault.error_code);
+		walker->error_code |= PFERR_RSVD_MASK;
+	trace_kvm_mmu_walker_error(walker->error_code);
 	return 0;
 }
 
-static int FNAME(walk_addr)(struct guest_walker *walker,
-			    struct kvm_vcpu *vcpu, gva_t addr, u32 access)
-{
-	return FNAME(walk_addr_generic)(walker, vcpu, &vcpu->arch.mmu, addr,
-					access);
-}
-
-static int FNAME(walk_addr_nested)(struct guest_walker *walker,
-				   struct kvm_vcpu *vcpu, gva_t addr,
-				   u32 access)
-{
-	return FNAME(walk_addr_generic)(walker, vcpu, &vcpu->arch.nested_mmu,
-					addr, access);
-}
-
-static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu,
-				    struct kvm_mmu_page *sp, u64 *spte,
-				    pt_element_t gpte)
-{
-	u64 nonpresent = shadow_trap_nonpresent_pte;
-
-	if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL))
-		goto no_present;
-
-	if (!is_present_gpte(gpte)) {
-		if (!sp->unsync)
-			nonpresent = shadow_notrap_nonpresent_pte;
-		goto no_present;
-	}
-
-	if (!(gpte & PT_ACCESSED_MASK))
-		goto no_present;
-
-	return false;
-
-no_present:
-	drop_spte(vcpu->kvm, spte, nonpresent);
-	return true;
-}
-
-static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
+static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
 			      u64 *spte, const void *pte)
 {
 	pt_element_t gpte;
@@ -334,11 +260,13 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
 	pfn_t pfn;
 
 	gpte = *(const pt_element_t *)pte;
-	if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte))
+	if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {
+		if (!is_present_gpte(gpte))
+			__set_spte(spte, shadow_notrap_nonpresent_pte);
 		return;
-
+	}
 	pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte);
-	pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
+	pte_access = page->role.access & FNAME(gpte_access)(vcpu, gpte);
 	if (gpte_to_gfn(gpte) != vcpu->arch.update_pte.gfn)
 		return;
 	pfn = vcpu->arch.update_pte.pfn;
@@ -348,181 +276,91 @@ static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
 		return;
 	kvm_get_pfn(pfn);
 	/*
-	 * we call mmu_set_spte() with host_writable = true beacuse that
+	 * we call mmu_set_spte() with reset_host_protection = true beacuse that
 	 * vcpu->arch.update_pte.pfn was fetched from get_user_pages(write = 1).
 	 */
-	mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0,
-		     is_dirty_gpte(gpte), NULL, PT_PAGE_TABLE_LEVEL,
+	mmu_set_spte(vcpu, spte, page->role.access, pte_access, 0, 0,
+		     gpte & PT_DIRTY_MASK, NULL, PT_PAGE_TABLE_LEVEL,
 		     gpte_to_gfn(gpte), pfn, true, true);
 }
 
-static bool FNAME(gpte_changed)(struct kvm_vcpu *vcpu,
-				struct guest_walker *gw, int level)
-{
-	pt_element_t curr_pte;
-	gpa_t base_gpa, pte_gpa = gw->pte_gpa[level - 1];
-	u64 mask;
-	int r, index;
-
-	if (level == PT_PAGE_TABLE_LEVEL) {
-		mask = PTE_PREFETCH_NUM * sizeof(pt_element_t) - 1;
-		base_gpa = pte_gpa & ~mask;
-		index = (pte_gpa - base_gpa) / sizeof(pt_element_t);
-
-		r = kvm_read_guest_atomic(vcpu->kvm, base_gpa,
-				gw->prefetch_ptes, sizeof(gw->prefetch_ptes));
-		curr_pte = gw->prefetch_ptes[index];
-	} else
-		r = kvm_read_guest_atomic(vcpu->kvm, pte_gpa,
-				  &curr_pte, sizeof(curr_pte));
-
-	return r || curr_pte != gw->ptes[level - 1];
-}
-
-static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw,
-				u64 *sptep)
-{
-	struct kvm_mmu_page *sp;
-	pt_element_t *gptep = gw->prefetch_ptes;
-	u64 *spte;
-	int i;
-
-	sp = page_header(__pa(sptep));
-
-	if (sp->role.level > PT_PAGE_TABLE_LEVEL)
-		return;
-
-	if (sp->role.direct)
-		return __direct_pte_prefetch(vcpu, sp, sptep);
-
-	i = (sptep - sp->spt) & ~(PTE_PREFETCH_NUM - 1);
-	spte = sp->spt + i;
-
-	for (i = 0; i < PTE_PREFETCH_NUM; i++, spte++) {
-		pt_element_t gpte;
-		unsigned pte_access;
-		gfn_t gfn;
-		pfn_t pfn;
-		bool dirty;
-
-		if (spte == sptep)
-			continue;
-
-		if (*spte != shadow_trap_nonpresent_pte)
-			continue;
-
-		gpte = gptep[i];
-
-		if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte))
-			continue;
-
-		pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
-		gfn = gpte_to_gfn(gpte);
-		dirty = is_dirty_gpte(gpte);
-		pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn,
-				      (pte_access & ACC_WRITE_MASK) && dirty);
-		if (is_error_pfn(pfn)) {
-			kvm_release_pfn_clean(pfn);
-			break;
-		}
-
-		mmu_set_spte(vcpu, spte, sp->role.access, pte_access, 0, 0,
-			     dirty, NULL, PT_PAGE_TABLE_LEVEL, gfn,
-			     pfn, true, true);
-	}
-}
-
 /*
  * Fetch a shadow pte for a specific level in the paging hierarchy.
  */
 static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 			 struct guest_walker *gw,
 			 int user_fault, int write_fault, int hlevel,
-			 int *ptwrite, pfn_t pfn, bool map_writable,
-			 bool prefault)
+			 int *ptwrite, pfn_t pfn)
 {
 	unsigned access = gw->pt_access;
-	struct kvm_mmu_page *sp = NULL;
-	bool dirty = is_dirty_gpte(gw->ptes[gw->level - 1]);
-	int top_level;
-	unsigned direct_access;
-	struct kvm_shadow_walk_iterator it;
+	struct kvm_mmu_page *shadow_page;
+	u64 spte, *sptep = NULL;
+	int direct;
+	gfn_t table_gfn;
+	int r;
+	int level;
+	pt_element_t curr_pte;
+	struct kvm_shadow_walk_iterator iterator;
 
 	if (!is_present_gpte(gw->ptes[gw->level - 1]))
 		return NULL;
 
-	direct_access = gw->pt_access & gw->pte_access;
-	if (!dirty)
-		direct_access &= ~ACC_WRITE_MASK;
-
-	top_level = vcpu->arch.mmu.root_level;
-	if (top_level == PT32E_ROOT_LEVEL)
-		top_level = PT32_ROOT_LEVEL;
-	/*
-	 * Verify that the top-level gpte is still there.  Since the page
-	 * is a root page, it is either write protected (and cannot be
-	 * changed from now on) or it is invalid (in which case, we don't
-	 * really care if it changes underneath us after this point).
-	 */
-	if (FNAME(gpte_changed)(vcpu, gw, top_level))
-		goto out_gpte_changed;
-
-	for (shadow_walk_init(&it, vcpu, addr);
-	     shadow_walk_okay(&it) && it.level > gw->level;
-	     shadow_walk_next(&it)) {
-		gfn_t table_gfn;
-
-		drop_large_spte(vcpu, it.sptep);
-
-		sp = NULL;
-		if (!is_shadow_present_pte(*it.sptep)) {
-			table_gfn = gw->table_gfn[it.level - 2];
-			sp = kvm_mmu_get_page(vcpu, table_gfn, addr, it.level-1,
-					      false, access, it.sptep);
+	for_each_shadow_entry(vcpu, addr, iterator) {
+		level = iterator.level;
+		sptep = iterator.sptep;
+		if (iterator.level == hlevel) {
+			mmu_set_spte(vcpu, sptep, access,
+				     gw->pte_access & access,
+				     user_fault, write_fault,
+				     gw->ptes[gw->level-1] & PT_DIRTY_MASK,
+				     ptwrite, level,
+				     gw->gfn, pfn, false, true);
+			break;
 		}
 
-		/*
-		 * Verify that the gpte in the page we've just write
-		 * protected is still there.
-		 */
-		if (FNAME(gpte_changed)(vcpu, gw, it.level - 1))
-			goto out_gpte_changed;
-
-		if (sp)
-			link_shadow_page(it.sptep, sp);
-	}
-
-	for (;
-	     shadow_walk_okay(&it) && it.level > hlevel;
-	     shadow_walk_next(&it)) {
-		gfn_t direct_gfn;
-
-		validate_direct_spte(vcpu, it.sptep, direct_access);
-
-		drop_large_spte(vcpu, it.sptep);
-
-		if (is_shadow_present_pte(*it.sptep))
+		if (is_shadow_present_pte(*sptep) && !is_large_pte(*sptep))
 			continue;
 
-		direct_gfn = gw->gfn & ~(KVM_PAGES_PER_HPAGE(it.level) - 1);
-
-		sp = kvm_mmu_get_page(vcpu, direct_gfn, addr, it.level-1,
-				      true, direct_access, it.sptep);
-		link_shadow_page(it.sptep, sp);
-	}
+		if (is_large_pte(*sptep)) {
+			rmap_remove(vcpu->kvm, sptep);
+			__set_spte(sptep, shadow_trap_nonpresent_pte);
+			kvm_flush_remote_tlbs(vcpu->kvm);
+		}
 
-	mmu_set_spte(vcpu, it.sptep, access, gw->pte_access & access,
-		     user_fault, write_fault, dirty, ptwrite, it.level,
-		     gw->gfn, pfn, prefault, map_writable);
-	FNAME(pte_prefetch)(vcpu, gw, it.sptep);
+		if (level <= gw->level) {
+			int delta = level - gw->level + 1;
+			direct = 1;
+			if (!is_dirty_gpte(gw->ptes[level - delta]))
+				access &= ~ACC_WRITE_MASK;
+			table_gfn = gpte_to_gfn(gw->ptes[level - delta]);
+			/* advance table_gfn when emulating 1gb pages with 4k */
+			if (delta == 0)
+				table_gfn += PT_INDEX(addr, level);
+		} else {
+			direct = 0;
+			table_gfn = gw->table_gfn[level - 2];
+		}
+		shadow_page = kvm_mmu_get_page(vcpu, table_gfn, addr, level-1,
+					       direct, access, sptep);
+		if (!direct) {
+			r = kvm_read_guest_atomic(vcpu->kvm,
+						  gw->pte_gpa[level - 2],
+						  &curr_pte, sizeof(curr_pte));
+			if (r || curr_pte != gw->ptes[level - 2]) {
+				kvm_mmu_put_page(shadow_page, sptep);
+				kvm_release_pfn_clean(pfn);
+				sptep = NULL;
+				break;
+			}
+		}
 
-	return it.sptep;
+		spte = __pa(shadow_page->spt)
+			| PT_PRESENT_MASK | PT_ACCESSED_MASK
+			| PT_WRITABLE_MASK | PT_USER_MASK;
+		*sptep = spte;
+	}
 
-out_gpte_changed:
-	if (sp)
-		kvm_mmu_put_page(sp, it.sptep);
-	kvm_release_pfn_clean(pfn);
-	return NULL;
+	return sptep;
 }
 
 /*
@@ -539,22 +377,22 @@ out_gpte_changed:
  *  Returns: 1 if we need to emulate the instruction, 0 otherwise, or
  *           a negative value on error.
  */
-static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
-			     bool prefault)
+static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
+			       u32 error_code)
 {
 	int write_fault = error_code & PFERR_WRITE_MASK;
 	int user_fault = error_code & PFERR_USER_MASK;
+	int fetch_fault = error_code & PFERR_FETCH_MASK;
 	struct guest_walker walker;
 	u64 *sptep;
 	int write_pt = 0;
 	int r;
 	pfn_t pfn;
 	int level = PT_PAGE_TABLE_LEVEL;
-	int force_pt_level;
 	unsigned long mmu_seq;
-	bool map_writable;
 
 	pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code);
+	kvm_mmu_audit(vcpu, "pre page fault");
 
 	r = mmu_topup_memory_caches(vcpu);
 	if (r)
@@ -563,52 +401,41 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 	/*
 	 * Look up the guest pte for the faulting address.
 	 */
-	r = FNAME(walk_addr)(&walker, vcpu, addr, error_code);
+	r = FNAME(walk_addr)(&walker, vcpu, addr, write_fault, user_fault,
+			     fetch_fault);
 
 	/*
 	 * The page is not mapped by the guest.  Let the guest handle it.
 	 */
 	if (!r) {
 		pgprintk("%s: guest page fault\n", __func__);
-		if (!prefault) {
-			inject_page_fault(vcpu, &walker.fault);
-			/* reset fork detector */
-			vcpu->arch.last_pt_write_count = 0;
-		}
+		inject_page_fault(vcpu, addr, walker.error_code);
+		vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
 		return 0;
 	}
 
-	if (walker.level >= PT_DIRECTORY_LEVEL)
-		force_pt_level = mapping_level_dirty_bitmap(vcpu, walker.gfn);
-	else
-		force_pt_level = 1;
-	if (!force_pt_level) {
+	if (walker.level >= PT_DIRECTORY_LEVEL) {
 		level = min(walker.level, mapping_level(vcpu, walker.gfn));
 		walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1);
 	}
 
 	mmu_seq = vcpu->kvm->mmu_notifier_seq;
 	smp_rmb();
-
-	if (try_async_pf(vcpu, prefault, walker.gfn, addr, &pfn, write_fault,
-			 &map_writable))
-		return 0;
+	pfn = gfn_to_pfn(vcpu->kvm, walker.gfn);
 
 	/* mmio */
-	if (is_error_pfn(pfn))
-		return kvm_handle_bad_page(vcpu->kvm, walker.gfn, pfn);
+	if (is_error_pfn(pfn)) {
+		pgprintk("gfn %lx is mmio\n", walker.gfn);
+		kvm_release_pfn_clean(pfn);
+		return 1;
+	}
 
 	spin_lock(&vcpu->kvm->mmu_lock);
 	if (mmu_notifier_retry(vcpu, mmu_seq))
 		goto out_unlock;
-
-	trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT);
 	kvm_mmu_free_some_pages(vcpu);
-	if (!force_pt_level)
-		transparent_hugepage_adjust(vcpu, &walker.gfn, &pfn, &level);
 	sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
-			     level, &write_pt, pfn, map_writable, prefault);
-	(void)sptep;
+			     level, &write_pt, pfn);
 	pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __func__,
 		 sptep, *sptep, write_pt);
 
@@ -616,7 +443,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code,
 		vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
 
 	++vcpu->stat.pf_fixed;
-	trace_kvm_mmu_audit(vcpu, AUDIT_POST_PAGE_FAULT);
+	kvm_mmu_audit(vcpu, "post page fault (fixed)");
 	spin_unlock(&vcpu->kvm->mmu_lock);
 
 	return write_pt;
@@ -630,8 +457,6 @@ out_unlock:
 static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
 {
 	struct kvm_shadow_walk_iterator iterator;
-	struct kvm_mmu_page *sp;
-	gpa_t pte_gpa = -1;
 	int level;
 	u64 *sptep;
 	int need_flush = 0;
@@ -642,83 +467,46 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva)
 		level = iterator.level;
 		sptep = iterator.sptep;
 
-		sp = page_header(__pa(sptep));
-		if (is_last_spte(*sptep, level)) {
-			int offset, shift;
-
-			if (!sp->unsync)
-				break;
-
-			shift = PAGE_SHIFT -
-				  (PT_LEVEL_BITS - PT64_LEVEL_BITS) * level;
-			offset = sp->role.quadrant << shift;
-
-			pte_gpa = (sp->gfn << PAGE_SHIFT) + offset;
-			pte_gpa += (sptep - sp->spt) * sizeof(pt_element_t);
+		if (level == PT_PAGE_TABLE_LEVEL  ||
+		    ((level == PT_DIRECTORY_LEVEL && is_large_pte(*sptep))) ||
+		    ((level == PT_PDPE_LEVEL && is_large_pte(*sptep)))) {
 
 			if (is_shadow_present_pte(*sptep)) {
+				rmap_remove(vcpu->kvm, sptep);
 				if (is_large_pte(*sptep))
 					--vcpu->kvm->stat.lpages;
-				drop_spte(vcpu->kvm, sptep,
-					  shadow_trap_nonpresent_pte);
 				need_flush = 1;
-			} else
-				__set_spte(sptep, shadow_trap_nonpresent_pte);
+			}
+			__set_spte(sptep, shadow_trap_nonpresent_pte);
 			break;
 		}
 
-		if (!is_shadow_present_pte(*sptep) || !sp->unsync_children)
+		if (!is_shadow_present_pte(*sptep))
 			break;
 	}
 
 	if (need_flush)
 		kvm_flush_remote_tlbs(vcpu->kvm);
-
-	atomic_inc(&vcpu->kvm->arch.invlpg_counter);
-
 	spin_unlock(&vcpu->kvm->mmu_lock);
-
-	if (pte_gpa == -1)
-		return;
-
-	if (mmu_topup_memory_caches(vcpu))
-		return;
-	kvm_mmu_pte_write(vcpu, pte_gpa, NULL, sizeof(pt_element_t), 0);
 }
 
 static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr, u32 access,
-			       struct x86_exception *exception)
+			       u32 *error)
 {
 	struct guest_walker walker;
 	gpa_t gpa = UNMAPPED_GVA;
 	int r;
 
-	r = FNAME(walk_addr)(&walker, vcpu, vaddr, access);
+	r = FNAME(walk_addr)(&walker, vcpu, vaddr,
+			     !!(access & PFERR_WRITE_MASK),
+			     !!(access & PFERR_USER_MASK),
+			     !!(access & PFERR_FETCH_MASK));
 
 	if (r) {
 		gpa = gfn_to_gpa(walker.gfn);
 		gpa |= vaddr & ~PAGE_MASK;
-	} else if (exception)
-		*exception = walker.fault;
-
-	return gpa;
-}
-
-static gpa_t FNAME(gva_to_gpa_nested)(struct kvm_vcpu *vcpu, gva_t vaddr,
-				      u32 access,
-				      struct x86_exception *exception)
-{
-	struct guest_walker walker;
-	gpa_t gpa = UNMAPPED_GVA;
-	int r;
-
-	r = FNAME(walk_addr_nested)(&walker, vcpu, vaddr, access);
-
-	if (r) {
-		gpa = gfn_to_gpa(walker.gfn);
-		gpa |= vaddr & ~PAGE_MASK;
-	} else if (exception)
-		*exception = walker.fault;
+	} else if (error)
+		*error = walker.error_code;
 
 	return gpa;
 }
@@ -757,68 +545,59 @@ static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
  * Using the cached information from sp->gfns is safe because:
  * - The spte has a reference to the struct page, so the pfn for a given gfn
  *   can't change unless all sptes pointing to it are nuked first.
- *
- * Note:
- *   We should flush all tlbs if spte is dropped even though guest is
- *   responsible for it. Since if we don't, kvm_mmu_notifier_invalidate_page
- *   and kvm_mmu_notifier_invalidate_range_start detect the mapping page isn't
- *   used by guest then tlbs are not flushed, so guest is allowed to access the
- *   freed pages.
- *   And we increase kvm->tlbs_dirty to delay tlbs flush in this case.
+ * - Alias changes zap the entire shadow cache.
  */
 static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 {
 	int i, offset, nr_present;
-	bool host_writable;
-	gpa_t first_pte_gpa;
+	bool reset_host_protection;
 
 	offset = nr_present = 0;
 
-	/* direct kvm_mmu_page can not be unsync. */
-	BUG_ON(sp->role.direct);
-
 	if (PTTYPE == 32)
 		offset = sp->role.quadrant << PT64_LEVEL_BITS;
 
-	first_pte_gpa = gfn_to_gpa(sp->gfn) + offset * sizeof(pt_element_t);
-
 	for (i = 0; i < PT64_ENT_PER_PAGE; i++) {
 		unsigned pte_access;
 		pt_element_t gpte;
 		gpa_t pte_gpa;
-		gfn_t gfn;
+		gfn_t gfn = sp->gfns[i];
 
 		if (!is_shadow_present_pte(sp->spt[i]))
 			continue;
 
-		pte_gpa = first_pte_gpa + i * sizeof(pt_element_t);
+		pte_gpa = gfn_to_gpa(sp->gfn);
+		pte_gpa += (i+offset) * sizeof(pt_element_t);
 
 		if (kvm_read_guest_atomic(vcpu->kvm, pte_gpa, &gpte,
 					  sizeof(pt_element_t)))
 			return -EINVAL;
 
-		gfn = gpte_to_gfn(gpte);
-
-		if (FNAME(prefetch_invalid_gpte)(vcpu, sp, &sp->spt[i], gpte)) {
-			vcpu->kvm->tlbs_dirty++;
-			continue;
-		}
+		if (gpte_to_gfn(gpte) != gfn || !is_present_gpte(gpte) ||
+		    !(gpte & PT_ACCESSED_MASK)) {
+			u64 nonpresent;
 
-		if (gfn != sp->gfns[i]) {
-			drop_spte(vcpu->kvm, &sp->spt[i],
-				      shadow_trap_nonpresent_pte);
-			vcpu->kvm->tlbs_dirty++;
+			rmap_remove(vcpu->kvm, &sp->spt[i]);
+			if (is_present_gpte(gpte))
+				nonpresent = shadow_trap_nonpresent_pte;
+			else
+				nonpresent = shadow_notrap_nonpresent_pte;
+			__set_spte(&sp->spt[i], nonpresent);
 			continue;
 		}
 
 		nr_present++;
 		pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
-		host_writable = sp->spt[i] & SPTE_HOST_WRITEABLE;
-
+		if (!(sp->spt[i] & SPTE_HOST_WRITEABLE)) {
+			pte_access &= ~ACC_WRITE_MASK;
+			reset_host_protection = 0;
+		} else {
+			reset_host_protection = 1;
+		}
 		set_spte(vcpu, &sp->spt[i], pte_access, 0, 0,
 			 is_dirty_gpte(gpte), PT_PAGE_TABLE_LEVEL, gfn,
 			 spte_to_pfn(sp->spt[i]), true, false,
-			 host_writable);
+			 reset_host_protection);
 	}
 
 	return !nr_present;