Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - selftests improvements
   - large PUD support for HugeTLB
   - single-stepping fixes
   - improved tracing
   - various timer and vGIC fixes

  x86:
   - Processor Tracing virtualization
   - STIBP support
   - some correctness fixes
   - refactorings and splitting of vmx.c
   - use the Hyper-V range TLB flush hypercall
   - reduce order of vcpu struct
   - WBNOINVD support
   - do not use -ftrace for __noclone functions
   - nested guest support for PAUSE filtering on AMD
   - more Hyper-V enlightenments (direct mode for synthetic timers)

  PPC:
   -  nested VFIO

  s390:
   - bugfixes only this time"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits)
  KVM: x86: Add CPUID support for new instruction WBNOINVD
  kvm: selftests: ucall: fix exit mmio address guessing
  Revert "compiler-gcc: disable -ftracer for __noclone functions"
  KVM: VMX: Move VM-Enter + VM-Exit handling to non-inline sub-routines
  KVM: VMX: Explicitly reference RCX as the vmx_vcpu pointer in asm blobs
  KVM: x86: Use jmp to invoke kvm_spurious_fault() from .fixup
  MAINTAINERS: Add arch/x86/kvm sub-directories to existing KVM/x86 entry
  KVM/x86: Use SVM assembly instruction mnemonics instead of .byte streams
  KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()
  KVM/MMU: Flush tlb directly in kvm_set_pte_rmapp()
  KVM/MMU: Move tlb flush in kvm_set_pte_rmapp() to kvm_mmu_notifier_change_pte()
  KVM: Make kvm_set_spte_hva() return int
  KVM: Replace old tlb flush function with new one to flush a specified range.
  KVM/MMU: Add tlb flush with range helper function
  KVM/VMX: Add hv tlb range flush support
  x86/hyper-v: Add HvFlushGuestAddressList hypercall support
  KVM: Add tlb_remote_flush_with_range callback in kvm_x86_ops
  KVM: x86: Disable Intel PT when VMXON in L1 guest
  KVM: x86: Set intercept for Intel PT MSRs read/write
  KVM: x86: Implement Intel PT MSRs read/write emulation
  ...

virt/kvm/arm/arch_timer.c

@@ -70,11 +70,9 @@ static void soft_timer_start(struct hrtimer *hrt, u64 ns)
 		      HRTIMER_MODE_ABS);
 }
 
-static void soft_timer_cancel(struct hrtimer *hrt, struct work_struct *work)
+static void soft_timer_cancel(struct hrtimer *hrt)
 {
 	hrtimer_cancel(hrt);
-	if (work)
-		cancel_work_sync(work);
 }
 
 static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
@@ -102,23 +100,6 @@ static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-/*
- * Work function for handling the backup timer that we schedule when a vcpu is
- * no longer running, but had a timer programmed to fire in the future.
- */
-static void kvm_timer_inject_irq_work(struct work_struct *work)
-{
-	struct kvm_vcpu *vcpu;
-
-	vcpu = container_of(work, struct kvm_vcpu, arch.timer_cpu.expired);
-
-	/*
-	 * If the vcpu is blocked we want to wake it up so that it will see
-	 * the timer has expired when entering the guest.
-	 */
-	kvm_vcpu_wake_up(vcpu);
-}
-
 static u64 kvm_timer_compute_delta(struct arch_timer_context *timer_ctx)
 {
 	u64 cval, now;
@@ -188,7 +169,7 @@ static enum hrtimer_restart kvm_bg_timer_expire(struct hrtimer *hrt)
 		return HRTIMER_RESTART;
 	}
 
-	schedule_work(&timer->expired);
+	kvm_vcpu_wake_up(vcpu);
 	return HRTIMER_NORESTART;
 }
 
@@ -300,7 +281,7 @@ static void phys_timer_emulate(struct kvm_vcpu *vcpu)
 	 * then we also don't need a soft timer.
 	 */
 	if (kvm_timer_should_fire(ptimer) || !kvm_timer_irq_can_fire(ptimer)) {
-		soft_timer_cancel(&timer->phys_timer, NULL);
+		soft_timer_cancel(&timer->phys_timer);
 		return;
 	}
 
@@ -426,7 +407,7 @@ void kvm_timer_unschedule(struct kvm_vcpu *vcpu)
 
 	vtimer_restore_state(vcpu);
 
-	soft_timer_cancel(&timer->bg_timer, &timer->expired);
+	soft_timer_cancel(&timer->bg_timer);
 }
 
 static void set_cntvoff(u64 cntvoff)
@@ -544,7 +525,7 @@ void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
 	 * In any case, we re-schedule the hrtimer for the physical timer when
 	 * coming back to the VCPU thread in kvm_timer_vcpu_load().
 	 */
-	soft_timer_cancel(&timer->phys_timer, NULL);
+	soft_timer_cancel(&timer->phys_timer);
 
 	/*
 	 * The kernel may decide to run userspace after calling vcpu_put, so
@@ -637,7 +618,6 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
 	update_vtimer_cntvoff(vcpu, kvm_phys_timer_read());
 	vcpu_ptimer(vcpu)->cntvoff = 0;
 
-	INIT_WORK(&timer->expired, kvm_timer_inject_irq_work);
 	hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 	timer->bg_timer.function = kvm_bg_timer_expire;
 
@@ -792,11 +772,8 @@ out_free_irq:
 void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
 {
 	struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
-	struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
 
-	soft_timer_cancel(&timer->bg_timer, &timer->expired);
-	soft_timer_cancel(&timer->phys_timer, NULL);
-	kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq);
+	soft_timer_cancel(&timer->bg_timer);
 }
 
 static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)

virt/kvm/arm/arm.c

@@ -66,7 +66,7 @@ static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu);
 static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
 static u32 kvm_next_vmid;
 static unsigned int kvm_vmid_bits __read_mostly;
-static DEFINE_RWLOCK(kvm_vmid_lock);
+static DEFINE_SPINLOCK(kvm_vmid_lock);
 
 static bool vgic_present;
 
@@ -484,7 +484,9 @@ void force_vm_exit(const cpumask_t *mask)
  */
 static bool need_new_vmid_gen(struct kvm *kvm)
 {
-	return unlikely(kvm->arch.vmid_gen != atomic64_read(&kvm_vmid_gen));
+	u64 current_vmid_gen = atomic64_read(&kvm_vmid_gen);
+	smp_rmb(); /* Orders read of kvm_vmid_gen and kvm->arch.vmid */
+	return unlikely(READ_ONCE(kvm->arch.vmid_gen) != current_vmid_gen);
 }
 
 /**
@@ -499,16 +501,11 @@ static void update_vttbr(struct kvm *kvm)
 {
 	phys_addr_t pgd_phys;
 	u64 vmid, cnp = kvm_cpu_has_cnp() ? VTTBR_CNP_BIT : 0;
-	bool new_gen;
 
-	read_lock(&kvm_vmid_lock);
-	new_gen = need_new_vmid_gen(kvm);
-	read_unlock(&kvm_vmid_lock);
-
-	if (!new_gen)
+	if (!need_new_vmid_gen(kvm))
 		return;
 
-	write_lock(&kvm_vmid_lock);
+	spin_lock(&kvm_vmid_lock);
 
 	/*
 	 * We need to re-check the vmid_gen here to ensure that if another vcpu
@@ -516,7 +513,7 @@ static void update_vttbr(struct kvm *kvm)
 	 * use the same vmid.
 	 */
 	if (!need_new_vmid_gen(kvm)) {
-		write_unlock(&kvm_vmid_lock);
+		spin_unlock(&kvm_vmid_lock);
 		return;
 	}
 
@@ -539,7 +536,6 @@ static void update_vttbr(struct kvm *kvm)
 		kvm_call_hyp(__kvm_flush_vm_context);
 	}
 
-	kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen);
 	kvm->arch.vmid = kvm_next_vmid;
 	kvm_next_vmid++;
 	kvm_next_vmid &= (1 << kvm_vmid_bits) - 1;
@@ -550,7 +546,10 @@ static void update_vttbr(struct kvm *kvm)
 	vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK(kvm_vmid_bits);
 	kvm->arch.vttbr = kvm_phys_to_vttbr(pgd_phys) | vmid | cnp;
 
-	write_unlock(&kvm_vmid_lock);
+	smp_wmb();
+	WRITE_ONCE(kvm->arch.vmid_gen, atomic64_read(&kvm_vmid_gen));
+
+	spin_unlock(&kvm_vmid_lock);
 }
 
 static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
@@ -674,8 +673,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		ret = kvm_handle_mmio_return(vcpu, vcpu->run);
 		if (ret)
 			return ret;
-		if (kvm_arm_handle_step_debug(vcpu, vcpu->run))
-			return 0;
 	}
 
 	if (run->immediate_exit)
@@ -1205,14 +1202,30 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
  */
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
 {
-	bool is_dirty = false;
+	bool flush = false;
 	int r;
 
 	mutex_lock(&kvm->slots_lock);
 
-	r = kvm_get_dirty_log_protect(kvm, log, &is_dirty);
+	r = kvm_get_dirty_log_protect(kvm, log, &flush);
 
-	if (is_dirty)
+	if (flush)
+		kvm_flush_remote_tlbs(kvm);
+
+	mutex_unlock(&kvm->slots_lock);
+	return r;
+}
+
+int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, struct kvm_clear_dirty_log *log)
+{
+	bool flush = false;
+	int r;
+
+	mutex_lock(&kvm->slots_lock);
+
+	r = kvm_clear_dirty_log_protect(kvm, log, &flush);
+
+	if (flush)
 		kvm_flush_remote_tlbs(kvm);
 
 	mutex_unlock(&kvm->slots_lock);

virt/kvm/arm/hyp/vgic-v3-sr.c

@@ -1012,8 +1012,10 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
 
 	esr = kvm_vcpu_get_hsr(vcpu);
 	if (vcpu_mode_is_32bit(vcpu)) {
-		if (!kvm_condition_valid(vcpu))
+		if (!kvm_condition_valid(vcpu)) {
+			__kvm_skip_instr(vcpu);
 			return 1;
+		}
 
 		sysreg = esr_cp15_to_sysreg(esr);
 	} else {
@@ -1123,6 +1125,8 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
 	rt = kvm_vcpu_sys_get_rt(vcpu);
 	fn(vcpu, vmcr, rt);
 
+	__kvm_skip_instr(vcpu);
+
 	return 1;
 }
 

virt/kvm/arm/mmio.c

@@ -117,6 +117,12 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		vcpu_set_reg(vcpu, vcpu->arch.mmio_decode.rt, data);
 	}
 
+	/*
+	 * The MMIO instruction is emulated and should not be re-executed
+	 * in the guest.
+	 */
+	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+
 	return 0;
 }
 
@@ -144,11 +150,6 @@ static int decode_hsr(struct kvm_vcpu *vcpu, bool *is_write, int *len)
 	vcpu->arch.mmio_decode.sign_extend = sign_extend;
 	vcpu->arch.mmio_decode.rt = rt;
 
-	/*
-	 * The MMIO instruction is emulated and should not be re-executed
-	 * in the guest.
-	 */
-	kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
 	return 0;
 }
 

virt/kvm/arm/mmu.c

@@ -115,6 +115,25 @@ static void stage2_dissolve_pmd(struct kvm *kvm, phys_addr_t addr, pmd_t *pmd)
 	put_page(virt_to_page(pmd));
 }
 
+/**
+ * stage2_dissolve_pud() - clear and flush huge PUD entry
+ * @kvm:	pointer to kvm structure.
+ * @addr:	IPA
+ * @pud:	pud pointer for IPA
+ *
+ * Function clears a PUD entry, flushes addr 1st and 2nd stage TLBs. Marks all
+ * pages in the range dirty.
+ */
+static void stage2_dissolve_pud(struct kvm *kvm, phys_addr_t addr, pud_t *pudp)
+{
+	if (!stage2_pud_huge(kvm, *pudp))
+		return;
+
+	stage2_pud_clear(kvm, pudp);
+	kvm_tlb_flush_vmid_ipa(kvm, addr);
+	put_page(virt_to_page(pudp));
+}
+
 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
 				  int min, int max)
 {
@@ -607,7 +626,7 @@ static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
 	addr = start;
 	do {
 		pte = pte_offset_kernel(pmd, addr);
-		kvm_set_pte(pte, pfn_pte(pfn, prot));
+		kvm_set_pte(pte, kvm_pfn_pte(pfn, prot));
 		get_page(virt_to_page(pte));
 		pfn++;
 	} while (addr += PAGE_SIZE, addr != end);
@@ -1022,7 +1041,7 @@ static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache
 	pmd_t *pmd;
 
 	pud = stage2_get_pud(kvm, cache, addr);
-	if (!pud)
+	if (!pud || stage2_pud_huge(kvm, *pud))
 		return NULL;
 
 	if (stage2_pud_none(kvm, *pud)) {
@@ -1083,29 +1102,103 @@ static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
 	return 0;
 }
 
-static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr)
+static int stage2_set_pud_huge(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
+			       phys_addr_t addr, const pud_t *new_pudp)
 {
+	pud_t *pudp, old_pud;
+
+	pudp = stage2_get_pud(kvm, cache, addr);
+	VM_BUG_ON(!pudp);
+
+	old_pud = *pudp;
+
+	/*
+	 * A large number of vcpus faulting on the same stage 2 entry,
+	 * can lead to a refault due to the
+	 * stage2_pud_clear()/tlb_flush(). Skip updating the page
+	 * tables if there is no change.
+	 */
+	if (pud_val(old_pud) == pud_val(*new_pudp))
+		return 0;
+
+	if (stage2_pud_present(kvm, old_pud)) {
+		stage2_pud_clear(kvm, pudp);
+		kvm_tlb_flush_vmid_ipa(kvm, addr);
+	} else {
+		get_page(virt_to_page(pudp));
+	}
+
+	kvm_set_pud(pudp, *new_pudp);
+	return 0;
+}
+
+/*
+ * stage2_get_leaf_entry - walk the stage2 VM page tables and return
+ * true if a valid and present leaf-entry is found. A pointer to the
+ * leaf-entry is returned in the appropriate level variable - pudpp,
+ * pmdpp, ptepp.
+ */
+static bool stage2_get_leaf_entry(struct kvm *kvm, phys_addr_t addr,
+				  pud_t **pudpp, pmd_t **pmdpp, pte_t **ptepp)
+{
+	pud_t *pudp;
 	pmd_t *pmdp;
 	pte_t *ptep;
 
-	pmdp = stage2_get_pmd(kvm, NULL, addr);
+	*pudpp = NULL;
+	*pmdpp = NULL;
+	*ptepp = NULL;
+
+	pudp = stage2_get_pud(kvm, NULL, addr);
+	if (!pudp || stage2_pud_none(kvm, *pudp) || !stage2_pud_present(kvm, *pudp))
+		return false;
+
+	if (stage2_pud_huge(kvm, *pudp)) {
+		*pudpp = pudp;
+		return true;
+	}
+
+	pmdp = stage2_pmd_offset(kvm, pudp, addr);
 	if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp))
 		return false;
 
-	if (pmd_thp_or_huge(*pmdp))
-		return kvm_s2pmd_exec(pmdp);
+	if (pmd_thp_or_huge(*pmdp)) {
+		*pmdpp = pmdp;
+		return true;
+	}
 
 	ptep = pte_offset_kernel(pmdp, addr);
 	if (!ptep || pte_none(*ptep) || !pte_present(*ptep))
 		return false;
 
-	return kvm_s2pte_exec(ptep);
+	*ptepp = ptep;
+	return true;
+}
+
+static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr)
+{
+	pud_t *pudp;
+	pmd_t *pmdp;
+	pte_t *ptep;
+	bool found;
+
+	found = stage2_get_leaf_entry(kvm, addr, &pudp, &pmdp, &ptep);
+	if (!found)
+		return false;
+
+	if (pudp)
+		return kvm_s2pud_exec(pudp);
+	else if (pmdp)
+		return kvm_s2pmd_exec(pmdp);
+	else
+		return kvm_s2pte_exec(ptep);
 }
 
 static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
 			  phys_addr_t addr, const pte_t *new_pte,
 			  unsigned long flags)
 {
+	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte, old_pte;
 	bool iomap = flags & KVM_S2PTE_FLAG_IS_IOMAP;
@@ -1114,7 +1207,31 @@ static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
 	VM_BUG_ON(logging_active && !cache);
 
 	/* Create stage-2 page table mapping - Levels 0 and 1 */
-	pmd = stage2_get_pmd(kvm, cache, addr);
+	pud = stage2_get_pud(kvm, cache, addr);
+	if (!pud) {
+		/*
+		 * Ignore calls from kvm_set_spte_hva for unallocated
+		 * address ranges.
+		 */
+		return 0;
+	}
+
+	/*
+	 * While dirty page logging - dissolve huge PUD, then continue
+	 * on to allocate page.
+	 */
+	if (logging_active)
+		stage2_dissolve_pud(kvm, addr, pud);
+
+	if (stage2_pud_none(kvm, *pud)) {
+		if (!cache)
+			return 0; /* ignore calls from kvm_set_spte_hva */
+		pmd = mmu_memory_cache_alloc(cache);
+		stage2_pud_populate(kvm, pud, pmd);
+		get_page(virt_to_page(pud));
+	}
+
+	pmd = stage2_pmd_offset(kvm, pud, addr);
 	if (!pmd) {
 		/*
 		 * Ignore calls from kvm_set_spte_hva for unallocated
@@ -1182,6 +1299,11 @@ static int stage2_pmdp_test_and_clear_young(pmd_t *pmd)
 	return stage2_ptep_test_and_clear_young((pte_t *)pmd);
 }
 
+static int stage2_pudp_test_and_clear_young(pud_t *pud)
+{
+	return stage2_ptep_test_and_clear_young((pte_t *)pud);
+}
+
 /**
  * kvm_phys_addr_ioremap - map a device range to guest IPA
  *
@@ -1202,7 +1324,7 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
 	pfn = __phys_to_pfn(pa);
 
 	for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
-		pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE);
+		pte_t pte = kvm_pfn_pte(pfn, PAGE_S2_DEVICE);
 
 		if (writable)
 			pte = kvm_s2pte_mkwrite(pte);
@@ -1234,7 +1356,7 @@ static bool transparent_hugepage_adjust(kvm_pfn_t *pfnp, phys_addr_t *ipap)
 	struct page *page = pfn_to_page(pfn);
 
 	/*
-	 * PageTransCompoungMap() returns true for THP and
+	 * PageTransCompoundMap() returns true for THP and
 	 * hugetlbfs. Make sure the adjustment is done only for THP
 	 * pages.
 	 */
@@ -1347,9 +1469,12 @@ static void  stage2_wp_puds(struct kvm *kvm, pgd_t *pgd,
 	do {
 		next = stage2_pud_addr_end(kvm, addr, end);
 		if (!stage2_pud_none(kvm, *pud)) {
-			/* TODO:PUD not supported, revisit later if supported */
-			BUG_ON(stage2_pud_huge(kvm, *pud));
-			stage2_wp_pmds(kvm, pud, addr, next);
+			if (stage2_pud_huge(kvm, *pud)) {
+				if (!kvm_s2pud_readonly(pud))
+					kvm_set_s2pud_readonly(pud);
+			} else {
+				stage2_wp_pmds(kvm, pud, addr, next);
+			}
 		}
 	} while (pud++, addr = next, addr != end);
 }
@@ -1392,7 +1517,7 @@ static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
  *
  * Called to start logging dirty pages after memory region
  * KVM_MEM_LOG_DIRTY_PAGES operation is called. After this function returns
- * all present PMD and PTEs are write protected in the memory region.
+ * all present PUD, PMD and PTEs are write protected in the memory region.
  * Afterwards read of dirty page log can be called.
  *
  * Acquires kvm_mmu_lock. Called with kvm->slots_lock mutex acquired,
@@ -1470,12 +1595,70 @@ static void kvm_send_hwpoison_signal(unsigned long address,
 	send_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, lsb, current);
 }
 
+static bool fault_supports_stage2_pmd_mappings(struct kvm_memory_slot *memslot,
+					       unsigned long hva)
+{
+	gpa_t gpa_start, gpa_end;
+	hva_t uaddr_start, uaddr_end;
+	size_t size;
+
+	size = memslot->npages * PAGE_SIZE;
+
+	gpa_start = memslot->base_gfn << PAGE_SHIFT;
+	gpa_end = gpa_start + size;
+
+	uaddr_start = memslot->userspace_addr;
+	uaddr_end = uaddr_start + size;
+
+	/*
+	 * Pages belonging to memslots that don't have the same alignment
+	 * within a PMD for userspace and IPA cannot be mapped with stage-2
+	 * PMD entries, because we'll end up mapping the wrong pages.
+	 *
+	 * Consider a layout like the following:
+	 *
+	 *    memslot->userspace_addr:
+	 *    +-----+--------------------+--------------------+---+
+	 *    |abcde|fgh  Stage-1 PMD    |    Stage-1 PMD   tv|xyz|
+	 *    +-----+--------------------+--------------------+---+
+	 *
+	 *    memslot->base_gfn << PAGE_SIZE:
+	 *      +---+--------------------+--------------------+-----+
+	 *      |abc|def  Stage-2 PMD    |    Stage-2 PMD     |tvxyz|
+	 *      +---+--------------------+--------------------+-----+
+	 *
+	 * If we create those stage-2 PMDs, we'll end up with this incorrect
+	 * mapping:
+	 *   d -> f
+	 *   e -> g
+	 *   f -> h
+	 */
+	if ((gpa_start & ~S2_PMD_MASK) != (uaddr_start & ~S2_PMD_MASK))
+		return false;
+
+	/*
+	 * Next, let's make sure we're not trying to map anything not covered
+	 * by the memslot. This means we have to prohibit PMD size mappings
+	 * for the beginning and end of a non-PMD aligned and non-PMD sized
+	 * memory slot (illustrated by the head and tail parts of the
+	 * userspace view above containing pages 'abcde' and 'xyz',
+	 * respectively).
+	 *
+	 * Note that it doesn't matter if we do the check using the
+	 * userspace_addr or the base_gfn, as both are equally aligned (per
+	 * the check above) and equally sized.
+	 */
+	return (hva & S2_PMD_MASK) >= uaddr_start &&
+	       (hva & S2_PMD_MASK) + S2_PMD_SIZE <= uaddr_end;
+}
+
 static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 			  struct kvm_memory_slot *memslot, unsigned long hva,
 			  unsigned long fault_status)
 {
 	int ret;
-	bool write_fault, exec_fault, writable, hugetlb = false, force_pte = false;
+	bool write_fault, writable, force_pte = false;
+	bool exec_fault, needs_exec;
 	unsigned long mmu_seq;
 	gfn_t gfn = fault_ipa >> PAGE_SHIFT;
 	struct kvm *kvm = vcpu->kvm;
@@ -1484,7 +1667,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	kvm_pfn_t pfn;
 	pgprot_t mem_type = PAGE_S2;
 	bool logging_active = memslot_is_logging(memslot);
-	unsigned long flags = 0;
+	unsigned long vma_pagesize, flags = 0;
 
 	write_fault = kvm_is_write_fault(vcpu);
 	exec_fault = kvm_vcpu_trap_is_iabt(vcpu);
@@ -1495,6 +1678,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 		return -EFAULT;
 	}
 
+	if (!fault_supports_stage2_pmd_mappings(memslot, hva))
+		force_pte = true;
+
+	if (logging_active)
+		force_pte = true;
+
 	/* Let's check if we will get back a huge page backed by hugetlbfs */
 	down_read(&current->mm->mmap_sem);
 	vma = find_vma_intersection(current->mm, hva, hva + 1);
@@ -1504,22 +1693,15 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 		return -EFAULT;
 	}
 
-	if (vma_kernel_pagesize(vma) == PMD_SIZE && !logging_active) {
-		hugetlb = true;
-		gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT;
-	} else {
-		/*
-		 * Pages belonging to memslots that don't have the same
-		 * alignment for userspace and IPA cannot be mapped using
-		 * block descriptors even if the pages belong to a THP for
-		 * the process, because the stage-2 block descriptor will
-		 * cover more than a single THP and we loose atomicity for
-		 * unmapping, updates, and splits of the THP or other pages
-		 * in the stage-2 block range.
-		 */
-		if ((memslot->userspace_addr & ~PMD_MASK) !=
-		    ((memslot->base_gfn << PAGE_SHIFT) & ~PMD_MASK))
-			force_pte = true;
+	vma_pagesize = vma_kernel_pagesize(vma);
+	/*
+	 * PUD level may not exist for a VM but PMD is guaranteed to
+	 * exist.
+	 */
+	if ((vma_pagesize == PMD_SIZE ||
+	     (vma_pagesize == PUD_SIZE && kvm_stage2_has_pud(kvm))) &&
+	    !force_pte) {
+		gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT;
 	}
 	up_read(&current->mm->mmap_sem);
 
@@ -1558,7 +1740,6 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 		 * should not be mapped with huge pages (it introduces churn
 		 * and performance degradation), so force a pte mapping.
 		 */
-		force_pte = true;
 		flags |= KVM_S2_FLAG_LOGGING_ACTIVE;
 
 		/*
@@ -1573,50 +1754,69 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	if (mmu_notifier_retry(kvm, mmu_seq))
 		goto out_unlock;
 
-	if (!hugetlb && !force_pte)
-		hugetlb = transparent_hugepage_adjust(&pfn, &fault_ipa);
+	if (vma_pagesize == PAGE_SIZE && !force_pte) {
+		/*
+		 * Only PMD_SIZE transparent hugepages(THP) are
+		 * currently supported. This code will need to be
+		 * updated to support other THP sizes.
+		 */
+		if (transparent_hugepage_adjust(&pfn, &fault_ipa))
+			vma_pagesize = PMD_SIZE;
+	}
 
-	if (hugetlb) {
-		pmd_t new_pmd = pfn_pmd(pfn, mem_type);
-		new_pmd = pmd_mkhuge(new_pmd);
-		if (writable) {
+	if (writable)
+		kvm_set_pfn_dirty(pfn);
+
+	if (fault_status != FSC_PERM)
+		clean_dcache_guest_page(pfn, vma_pagesize);
+
+	if (exec_fault)
+		invalidate_icache_guest_page(pfn, vma_pagesize);
+
+	/*
+	 * If we took an execution fault we have made the
+	 * icache/dcache coherent above and should now let the s2
+	 * mapping be executable.
+	 *
+	 * Write faults (!exec_fault && FSC_PERM) are orthogonal to
+	 * execute permissions, and we preserve whatever we have.
+	 */
+	needs_exec = exec_fault ||
+		(fault_status == FSC_PERM && stage2_is_exec(kvm, fault_ipa));
+
+	if (vma_pagesize == PUD_SIZE) {
+		pud_t new_pud = kvm_pfn_pud(pfn, mem_type);
+
+		new_pud = kvm_pud_mkhuge(new_pud);
+		if (writable)
+			new_pud = kvm_s2pud_mkwrite(new_pud);
+
+		if (needs_exec)
+			new_pud = kvm_s2pud_mkexec(new_pud);
+
+		ret = stage2_set_pud_huge(kvm, memcache, fault_ipa, &new_pud);
+	} else if (vma_pagesize == PMD_SIZE) {
+		pmd_t new_pmd = kvm_pfn_pmd(pfn, mem_type);
+
+		new_pmd = kvm_pmd_mkhuge(new_pmd);
+
+		if (writable)
 			new_pmd = kvm_s2pmd_mkwrite(new_pmd);
-			kvm_set_pfn_dirty(pfn);
-		}
 
-		if (fault_status != FSC_PERM)
-			clean_dcache_guest_page(pfn, PMD_SIZE);
-
-		if (exec_fault) {
+		if (needs_exec)
 			new_pmd = kvm_s2pmd_mkexec(new_pmd);
-			invalidate_icache_guest_page(pfn, PMD_SIZE);
-		} else if (fault_status == FSC_PERM) {
-			/* Preserve execute if XN was already cleared */
-			if (stage2_is_exec(kvm, fault_ipa))
-				new_pmd = kvm_s2pmd_mkexec(new_pmd);
-		}
 
 		ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd);
 	} else {
-		pte_t new_pte = pfn_pte(pfn, mem_type);
+		pte_t new_pte = kvm_pfn_pte(pfn, mem_type);
 
 		if (writable) {
 			new_pte = kvm_s2pte_mkwrite(new_pte);
-			kvm_set_pfn_dirty(pfn);
 			mark_page_dirty(kvm, gfn);
 		}
 
-		if (fault_status != FSC_PERM)
-			clean_dcache_guest_page(pfn, PAGE_SIZE);
-
-		if (exec_fault) {
+		if (needs_exec)
 			new_pte = kvm_s2pte_mkexec(new_pte);
-			invalidate_icache_guest_page(pfn, PAGE_SIZE);
-		} else if (fault_status == FSC_PERM) {
-			/* Preserve execute if XN was already cleared */
-			if (stage2_is_exec(kvm, fault_ipa))
-				new_pte = kvm_s2pte_mkexec(new_pte);
-		}
 
 		ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, flags);
 	}
@@ -1637,6 +1837,7 @@ out_unlock:
  */
 static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
 {
+	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte;
 	kvm_pfn_t pfn;
@@ -1646,24 +1847,23 @@ static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
 
 	spin_lock(&vcpu->kvm->mmu_lock);
 
-	pmd = stage2_get_pmd(vcpu->kvm, NULL, fault_ipa);
-	if (!pmd || pmd_none(*pmd))	/* Nothing there */
+	if (!stage2_get_leaf_entry(vcpu->kvm, fault_ipa, &pud, &pmd, &pte))
 		goto out;
 
-	if (pmd_thp_or_huge(*pmd)) {	/* THP, HugeTLB */
+	if (pud) {		/* HugeTLB */
+		*pud = kvm_s2pud_mkyoung(*pud);
+		pfn = kvm_pud_pfn(*pud);
+		pfn_valid = true;
+	} else	if (pmd) {	/* THP, HugeTLB */
 		*pmd = pmd_mkyoung(*pmd);
 		pfn = pmd_pfn(*pmd);
 		pfn_valid = true;
-		goto out;
+	} else {
+		*pte = pte_mkyoung(*pte);	/* Just a page... */
+		pfn = pte_pfn(*pte);
+		pfn_valid = true;
 	}
 
-	pte = pte_offset_kernel(pmd, fault_ipa);
-	if (pte_none(*pte))		/* Nothing there either */
-		goto out;
-
-	*pte = pte_mkyoung(*pte);	/* Just a page... */
-	pfn = pte_pfn(*pte);
-	pfn_valid = true;
 out:
 	spin_unlock(&vcpu->kvm->mmu_lock);
 	if (pfn_valid)
@@ -1849,14 +2049,14 @@ static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data
 }
 
 
-void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
+int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
 {
 	unsigned long end = hva + PAGE_SIZE;
 	kvm_pfn_t pfn = pte_pfn(pte);
 	pte_t stage2_pte;
 
 	if (!kvm->arch.pgd)
-		return;
+		return 0;
 
 	trace_kvm_set_spte_hva(hva);
 
@@ -1865,48 +2065,46 @@ void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
 	 * just like a translation fault and clean the cache to the PoC.
 	 */
 	clean_dcache_guest_page(pfn, PAGE_SIZE);
-	stage2_pte = pfn_pte(pfn, PAGE_S2);
+	stage2_pte = kvm_pfn_pte(pfn, PAGE_S2);
 	handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
+
+	return 0;
 }
 
 static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
 {
+	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte;
 
-	WARN_ON(size != PAGE_SIZE && size != PMD_SIZE);
-	pmd = stage2_get_pmd(kvm, NULL, gpa);
-	if (!pmd || pmd_none(*pmd))	/* Nothing there */
+	WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE);
+	if (!stage2_get_leaf_entry(kvm, gpa, &pud, &pmd, &pte))
 		return 0;
 
-	if (pmd_thp_or_huge(*pmd))	/* THP, HugeTLB */
+	if (pud)
+		return stage2_pudp_test_and_clear_young(pud);
+	else if (pmd)
 		return stage2_pmdp_test_and_clear_young(pmd);
-
-	pte = pte_offset_kernel(pmd, gpa);
-	if (pte_none(*pte))
-		return 0;
-
-	return stage2_ptep_test_and_clear_young(pte);
+	else
+		return stage2_ptep_test_and_clear_young(pte);
 }
 
 static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
 {
+	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte;
 
-	WARN_ON(size != PAGE_SIZE && size != PMD_SIZE);
-	pmd = stage2_get_pmd(kvm, NULL, gpa);
-	if (!pmd || pmd_none(*pmd))	/* Nothing there */
+	WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE);
+	if (!stage2_get_leaf_entry(kvm, gpa, &pud, &pmd, &pte))
 		return 0;
 
-	if (pmd_thp_or_huge(*pmd))		/* THP, HugeTLB */
+	if (pud)
+		return kvm_s2pud_young(*pud);
+	else if (pmd)
 		return pmd_young(*pmd);
-
-	pte = pte_offset_kernel(pmd, gpa);
-	if (!pte_none(*pte))		/* Just a page... */
+	else
 		return pte_young(*pte);
-
-	return 0;
 }
 
 int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)

virt/kvm/arm/trace.h

@@ -26,25 +26,25 @@ TRACE_EVENT(kvm_entry,
 );
 
 TRACE_EVENT(kvm_exit,
-	TP_PROTO(int idx, unsigned int exit_reason, unsigned long vcpu_pc),
-	TP_ARGS(idx, exit_reason, vcpu_pc),
+	TP_PROTO(int ret, unsigned int esr_ec, unsigned long vcpu_pc),
+	TP_ARGS(ret, esr_ec, vcpu_pc),
 
 	TP_STRUCT__entry(
-		__field(	int,		idx		)
-		__field(	unsigned int,	exit_reason	)
+		__field(	int,		ret		)
+		__field(	unsigned int,	esr_ec		)
 		__field(	unsigned long,	vcpu_pc		)
 	),
 
 	TP_fast_assign(
-		__entry->idx			= idx;
-		__entry->exit_reason		= exit_reason;
+		__entry->ret			= ARM_EXCEPTION_CODE(ret);
+		__entry->esr_ec = ARM_EXCEPTION_IS_TRAP(ret) ? esr_ec : 0;
 		__entry->vcpu_pc		= vcpu_pc;
 	),
 
 	TP_printk("%s: HSR_EC: 0x%04x (%s), PC: 0x%08lx",
-		  __print_symbolic(__entry->idx, kvm_arm_exception_type),
-		  __entry->exit_reason,
-		  __print_symbolic(__entry->exit_reason, kvm_arm_exception_class),
+		  __print_symbolic(__entry->ret, kvm_arm_exception_type),
+		  __entry->esr_ec,
+		  __print_symbolic(__entry->esr_ec, kvm_arm_exception_class),
 		  __entry->vcpu_pc)
 );
 

virt/kvm/arm/vgic/vgic-mmio.c

@@ -313,36 +313,30 @@ static void vgic_mmio_change_active(struct kvm_vcpu *vcpu, struct vgic_irq *irq,
 
 	spin_lock_irqsave(&irq->irq_lock, flags);
 
-	/*
-	 * If this virtual IRQ was written into a list register, we
-	 * have to make sure the CPU that runs the VCPU thread has
-	 * synced back the LR state to the struct vgic_irq.
-	 *
-	 * As long as the conditions below are true, we know the VCPU thread
-	 * may be on its way back from the guest (we kicked the VCPU thread in
-	 * vgic_change_active_prepare)  and still has to sync back this IRQ,
-	 * so we release and re-acquire the spin_lock to let the other thread
-	 * sync back the IRQ.
-	 *
-	 * When accessing VGIC state from user space, requester_vcpu is
-	 * NULL, which is fine, because we guarantee that no VCPUs are running
-	 * when accessing VGIC state from user space so irq->vcpu->cpu is
-	 * always -1.
-	 */
-	while (irq->vcpu && /* IRQ may have state in an LR somewhere */
-	       irq->vcpu != requester_vcpu && /* Current thread is not the VCPU thread */
-	       irq->vcpu->cpu != -1) /* VCPU thread is running */
-		cond_resched_lock(&irq->irq_lock);
-
 	if (irq->hw) {
 		vgic_hw_irq_change_active(vcpu, irq, active, !requester_vcpu);
 	} else {
 		u32 model = vcpu->kvm->arch.vgic.vgic_model;
+		u8 active_source;
 
 		irq->active = active;
+
+		/*
+		 * The GICv2 architecture indicates that the source CPUID for
+		 * an SGI should be provided during an EOI which implies that
+		 * the active state is stored somewhere, but at the same time
+		 * this state is not architecturally exposed anywhere and we
+		 * have no way of knowing the right source.
+		 *
+		 * This may lead to a VCPU not being able to receive
+		 * additional instances of a particular SGI after migration
+		 * for a GICv2 VM on some GIC implementations.  Oh well.
+		 */
+		active_source = (requester_vcpu) ? requester_vcpu->vcpu_id : 0;
+
 		if (model == KVM_DEV_TYPE_ARM_VGIC_V2 &&
 		    active && vgic_irq_is_sgi(irq->intid))
-			irq->active_source = requester_vcpu->vcpu_id;
+			irq->active_source = active_source;
 	}
 
 	if (irq->active)
@@ -368,14 +362,16 @@ static void vgic_mmio_change_active(struct kvm_vcpu *vcpu, struct vgic_irq *irq,
  */
 static void vgic_change_active_prepare(struct kvm_vcpu *vcpu, u32 intid)
 {
-	if (intid > VGIC_NR_PRIVATE_IRQS)
+	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3 ||
+	    intid > VGIC_NR_PRIVATE_IRQS)
 		kvm_arm_halt_guest(vcpu->kvm);
 }
 
 /* See vgic_change_active_prepare */
 static void vgic_change_active_finish(struct kvm_vcpu *vcpu, u32 intid)
 {
-	if (intid > VGIC_NR_PRIVATE_IRQS)
+	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3 ||
+	    intid > VGIC_NR_PRIVATE_IRQS)
 		kvm_arm_resume_guest(vcpu->kvm);
 }
 

virt/kvm/arm/vgic/vgic.c

@@ -103,13 +103,13 @@ struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
 {
 	/* SGIs and PPIs */
 	if (intid <= VGIC_MAX_PRIVATE) {
-		intid = array_index_nospec(intid, VGIC_MAX_PRIVATE);
+		intid = array_index_nospec(intid, VGIC_MAX_PRIVATE + 1);
 		return &vcpu->arch.vgic_cpu.private_irqs[intid];
 	}
 
 	/* SPIs */
-	if (intid <= VGIC_MAX_SPI) {
-		intid = array_index_nospec(intid, VGIC_MAX_SPI);
+	if (intid < (kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS)) {
+		intid = array_index_nospec(intid, kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS);
 		return &kvm->arch.vgic.spis[intid - VGIC_NR_PRIVATE_IRQS];
 	}
 
@@ -908,6 +908,7 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 	struct vgic_irq *irq;
 	bool pending = false;
 	unsigned long flags;
+	struct vgic_vmcr vmcr;
 
 	if (!vcpu->kvm->arch.vgic.enabled)
 		return false;
@@ -915,11 +916,15 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 	if (vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last)
 		return true;
 
+	vgic_get_vmcr(vcpu, &vmcr);
+
 	spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags);
 
 	list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) {
 		spin_lock(&irq->irq_lock);
-		pending = irq_is_pending(irq) && irq->enabled;
+		pending = irq_is_pending(irq) && irq->enabled &&
+			  !irq->active &&
+			  irq->priority < vmcr.pmr;
 		spin_unlock(&irq->irq_lock);
 
 		if (pending)

virt/kvm/async_pf.c

@@ -82,7 +82,7 @@ static void async_pf_execute(struct work_struct *work)
 	might_sleep();
 
 	/*
-	 * This work is run asynchromously to the task which owns
+	 * This work is run asynchronously to the task which owns
 	 * mm and might be done in another context, so we must
 	 * access remotely.
 	 */

virt/kvm/kvm_main.c

@@ -354,7 +354,10 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
 	idx = srcu_read_lock(&kvm->srcu);
 	spin_lock(&kvm->mmu_lock);
 	kvm->mmu_notifier_seq++;
-	kvm_set_spte_hva(kvm, address, pte);
+
+	if (kvm_set_spte_hva(kvm, address, pte))
+		kvm_flush_remote_tlbs(kvm);
+
 	spin_unlock(&kvm->mmu_lock);
 	srcu_read_unlock(&kvm->srcu, idx);
 }
@@ -1133,7 +1136,7 @@ EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
 /**
  * kvm_get_dirty_log_protect - get a snapshot of dirty pages, and if any pages
- *	are dirty write protect them for next write.
+ *	and reenable dirty page tracking for the corresponding pages.
  * @kvm:	pointer to kvm instance
  * @log:	slot id and address to which we copy the log
  * @is_dirty:	flag set if any page is dirty
@@ -1154,7 +1157,7 @@ EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
  *
  */
 int kvm_get_dirty_log_protect(struct kvm *kvm,
-			struct kvm_dirty_log *log, bool *is_dirty)
+			struct kvm_dirty_log *log, bool *flush)
 {
 	struct kvm_memslots *slots;
 	struct kvm_memory_slot *memslot;
@@ -1176,37 +1179,114 @@ int kvm_get_dirty_log_protect(struct kvm *kvm,
 		return -ENOENT;
 
 	n = kvm_dirty_bitmap_bytes(memslot);
+	*flush = false;
+	if (kvm->manual_dirty_log_protect) {
+		/*
+		 * Unlike kvm_get_dirty_log, we always return false in *flush,
+		 * because no flush is needed until KVM_CLEAR_DIRTY_LOG.  There
+		 * is some code duplication between this function and
+		 * kvm_get_dirty_log, but hopefully all architecture
+		 * transition to kvm_get_dirty_log_protect and kvm_get_dirty_log
+		 * can be eliminated.
+		 */
+		dirty_bitmap_buffer = dirty_bitmap;
+	} else {
+		dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
+		memset(dirty_bitmap_buffer, 0, n);
 
-	dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
-	memset(dirty_bitmap_buffer, 0, n);
+		spin_lock(&kvm->mmu_lock);
+		for (i = 0; i < n / sizeof(long); i++) {
+			unsigned long mask;
+			gfn_t offset;
 
-	spin_lock(&kvm->mmu_lock);
-	*is_dirty = false;
-	for (i = 0; i < n / sizeof(long); i++) {
-		unsigned long mask;
-		gfn_t offset;
+			if (!dirty_bitmap[i])
+				continue;
 
-		if (!dirty_bitmap[i])
-			continue;
+			*flush = true;
+			mask = xchg(&dirty_bitmap[i], 0);
+			dirty_bitmap_buffer[i] = mask;
 
-		*is_dirty = true;
-
-		mask = xchg(&dirty_bitmap[i], 0);
-		dirty_bitmap_buffer[i] = mask;
-
-		if (mask) {
-			offset = i * BITS_PER_LONG;
-			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
-								offset, mask);
+			if (mask) {
+				offset = i * BITS_PER_LONG;
+				kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
+									offset, mask);
+			}
 		}
+		spin_unlock(&kvm->mmu_lock);
 	}
 
-	spin_unlock(&kvm->mmu_lock);
 	if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
 		return -EFAULT;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);
+
+/**
+ * kvm_clear_dirty_log_protect - clear dirty bits in the bitmap
+ *	and reenable dirty page tracking for the corresponding pages.
+ * @kvm:	pointer to kvm instance
+ * @log:	slot id and address from which to fetch the bitmap of dirty pages
+ */
+int kvm_clear_dirty_log_protect(struct kvm *kvm,
+				struct kvm_clear_dirty_log *log, bool *flush)
+{
+	struct kvm_memslots *slots;
+	struct kvm_memory_slot *memslot;
+	int as_id, id, n;
+	gfn_t offset;
+	unsigned long i;
+	unsigned long *dirty_bitmap;
+	unsigned long *dirty_bitmap_buffer;
+
+	as_id = log->slot >> 16;
+	id = (u16)log->slot;
+	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
+		return -EINVAL;
+
+	if ((log->first_page & 63) || (log->num_pages & 63))
+		return -EINVAL;
+
+	slots = __kvm_memslots(kvm, as_id);
+	memslot = id_to_memslot(slots, id);
+
+	dirty_bitmap = memslot->dirty_bitmap;
+	if (!dirty_bitmap)
+		return -ENOENT;
+
+	n = kvm_dirty_bitmap_bytes(memslot);
+	*flush = false;
+	dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
+	if (copy_from_user(dirty_bitmap_buffer, log->dirty_bitmap, n))
+		return -EFAULT;
+
+	spin_lock(&kvm->mmu_lock);
+	for (offset = log->first_page,
+	     i = offset / BITS_PER_LONG, n = log->num_pages / BITS_PER_LONG; n--;
+	     i++, offset += BITS_PER_LONG) {
+		unsigned long mask = *dirty_bitmap_buffer++;
+		atomic_long_t *p = (atomic_long_t *) &dirty_bitmap[i];
+		if (!mask)
+			continue;
+
+		mask &= atomic_long_fetch_andnot(mask, p);
+
+		/*
+		 * mask contains the bits that really have been cleared.  This
+		 * never includes any bits beyond the length of the memslot (if
+		 * the length is not aligned to 64 pages), therefore it is not
+		 * a problem if userspace sets them in log->dirty_bitmap.
+		*/
+		if (mask) {
+			*flush = true;
+			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
+								offset, mask);
+		}
+	}
+	spin_unlock(&kvm->mmu_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_clear_dirty_log_protect);
 #endif
 
 bool kvm_largepages_enabled(void)
@@ -1928,32 +2008,33 @@ static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots,
 	gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
 	gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
 	gfn_t nr_pages_avail;
+	int r = start_gfn <= end_gfn ? 0 : -EINVAL;
 
 	ghc->gpa = gpa;
 	ghc->generation = slots->generation;
 	ghc->len = len;
-	ghc->memslot = __gfn_to_memslot(slots, start_gfn);
-	ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, NULL);
-	if (!kvm_is_error_hva(ghc->hva) && nr_pages_needed <= 1) {
-		ghc->hva += offset;
-	} else {
-		/*
-		 * If the requested region crosses two memslots, we still
-		 * verify that the entire region is valid here.
-		 */
-		while (start_gfn <= end_gfn) {
-			nr_pages_avail = 0;
-			ghc->memslot = __gfn_to_memslot(slots, start_gfn);
-			ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
-						   &nr_pages_avail);
-			if (kvm_is_error_hva(ghc->hva))
-				return -EFAULT;
-			start_gfn += nr_pages_avail;
-		}
-		/* Use the slow path for cross page reads and writes. */
-		ghc->memslot = NULL;
+	ghc->hva = KVM_HVA_ERR_BAD;
+
+	/*
+	 * If the requested region crosses two memslots, we still
+	 * verify that the entire region is valid here.
+	 */
+	while (!r && start_gfn <= end_gfn) {
+		ghc->memslot = __gfn_to_memslot(slots, start_gfn);
+		ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
+					   &nr_pages_avail);
+		if (kvm_is_error_hva(ghc->hva))
+			r = -EFAULT;
+		start_gfn += nr_pages_avail;
 	}
-	return 0;
+
+	/* Use the slow path for cross page reads and writes. */
+	if (!r && nr_pages_needed == 1)
+		ghc->hva += offset;
+	else
+		ghc->memslot = NULL;
+
+	return r;
 }
 
 int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
@@ -1965,7 +2046,8 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
 
 int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
-			   void *data, int offset, unsigned long len)
+				  void *data, unsigned int offset,
+				  unsigned long len)
 {
 	struct kvm_memslots *slots = kvm_memslots(kvm);
 	int r;
@@ -2948,6 +3030,10 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 #endif
 	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
 	case KVM_CAP_CHECK_EXTENSION_VM:
+	case KVM_CAP_ENABLE_CAP_VM:
+#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
+	case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT:
+#endif
 		return 1;
 #ifdef CONFIG_KVM_MMIO
 	case KVM_CAP_COALESCED_MMIO:
@@ -2971,6 +3057,28 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 	return kvm_vm_ioctl_check_extension(kvm, arg);
 }
 
+int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+						  struct kvm_enable_cap *cap)
+{
+	return -EINVAL;
+}
+
+static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
+					   struct kvm_enable_cap *cap)
+{
+	switch (cap->cap) {
+#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
+	case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT:
+		if (cap->flags || (cap->args[0] & ~1))
+			return -EINVAL;
+		kvm->manual_dirty_log_protect = cap->args[0];
+		return 0;
+#endif
+	default:
+		return kvm_vm_ioctl_enable_cap(kvm, cap);
+	}
+}
+
 static long kvm_vm_ioctl(struct file *filp,
 			   unsigned int ioctl, unsigned long arg)
 {
@@ -2984,6 +3092,15 @@ static long kvm_vm_ioctl(struct file *filp,
 	case KVM_CREATE_VCPU:
 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 		break;
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			goto out;
+		r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
+		break;
+	}
 	case KVM_SET_USER_MEMORY_REGION: {
 		struct kvm_userspace_memory_region kvm_userspace_mem;
 
@@ -3004,6 +3121,17 @@ static long kvm_vm_ioctl(struct file *filp,
 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
 		break;
 	}
+#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
+	case KVM_CLEAR_DIRTY_LOG: {
+		struct kvm_clear_dirty_log log;
+
+		r = -EFAULT;
+		if (copy_from_user(&log, argp, sizeof(log)))
+			goto out;
+		r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
+		break;
+	}
+#endif
 #ifdef CONFIG_KVM_MMIO
 	case KVM_REGISTER_COALESCED_MMIO: {
 		struct kvm_coalesced_mmio_zone zone;