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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
4  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
5  */
6 
7 #include <linux/bug.h>
8 #include <linux/cpu_pm.h>
9 #include <linux/entry-kvm.h>
10 #include <linux/errno.h>
11 #include <linux/err.h>
12 #include <linux/kvm_host.h>
13 #include <linux/list.h>
14 #include <linux/module.h>
15 #include <linux/vmalloc.h>
16 #include <linux/fs.h>
17 #include <linux/mman.h>
18 #include <linux/sched.h>
19 #include <linux/kvm.h>
20 #include <linux/kvm_irqfd.h>
21 #include <linux/irqbypass.h>
22 #include <linux/sched/stat.h>
23 #include <linux/shrinker.h>
24 #include <linux/psci.h>
25 #include <trace/events/kvm.h>
26 
27 #define CREATE_TRACE_POINTS
28 #include "trace_arm.h"
29 #include "hyp_trace.h"
30 
31 #include <linux/uaccess.h>
32 #include <asm/archrandom.h>
33 #include <asm/ptrace.h>
34 #include <asm/mman.h>
35 #include <asm/tlbflush.h>
36 #include <asm/cacheflush.h>
37 #include <asm/cpufeature.h>
38 #include <asm/virt.h>
39 #include <asm/kvm_arm.h>
40 #include <asm/kvm_asm.h>
41 #include <asm/kvm_mmu.h>
42 #include <asm/kvm_nested.h>
43 #include <asm/kvm_pkvm.h>
44 #include <asm/kvm_emulate.h>
45 #include <asm/sections.h>
46 
47 #include <kvm/arm_hypercalls.h>
48 #include <kvm/arm_pmu.h>
49 #include <kvm/arm_psci.h>
50 
51 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
52 
53 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
54 
55 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_base);
56 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
57 DECLARE_KVM_NVHE_PER_CPU(int, hyp_cpu_number);
58 
59 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
60 
61 static bool vgic_present, kvm_arm_initialised;
62 
63 static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized);
64 DEFINE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
65 
is_kvm_arm_initialised(void)66 bool is_kvm_arm_initialised(void)
67 {
68 	return kvm_arm_initialised;
69 }
70 
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)71 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
72 {
73 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
74 }
75 
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)76 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
77 			    struct kvm_enable_cap *cap)
78 {
79 	int r;
80 	u64 new_cap;
81 
82 	/* Capabilities with flags */
83 	switch (cap->cap) {
84 	case KVM_CAP_ARM_PROTECTED_VM:
85 		return pkvm_vm_ioctl_enable_cap(kvm, cap);
86 	default:
87 		if (cap->flags)
88 			return -EINVAL;
89 	}
90 
91 	/* Capabilities without flags */
92 	switch (cap->cap) {
93 	case KVM_CAP_ARM_NISV_TO_USER:
94 		if (kvm_vm_is_protected(kvm)) {
95 			r = -EINVAL;
96 		} else {
97 			r = 0;
98 			set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
99 				&kvm->arch.flags);
100 		}
101 		break;
102 	case KVM_CAP_ARM_MTE:
103 		mutex_lock(&kvm->lock);
104 		if (!system_supports_mte() ||
105 		    kvm_vm_is_protected(kvm) ||
106 		    kvm->created_vcpus) {
107 			r = -EINVAL;
108 		} else {
109 			r = 0;
110 			set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
111 		}
112 		mutex_unlock(&kvm->lock);
113 		break;
114 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
115 		r = 0;
116 		set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
117 		break;
118 	case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
119 		new_cap = cap->args[0];
120 
121 		mutex_lock(&kvm->slots_lock);
122 		/*
123 		 * To keep things simple, allow changing the chunk
124 		 * size only when no memory slots have been created.
125 		 */
126 		if (!kvm_are_all_memslots_empty(kvm)) {
127 			r = -EINVAL;
128 		} else if (new_cap && !kvm_is_block_size_supported(new_cap)) {
129 			r = -EINVAL;
130 		} else {
131 			r = 0;
132 			kvm->arch.mmu.split_page_chunk_size = new_cap;
133 		}
134 		mutex_unlock(&kvm->slots_lock);
135 		break;
136 	default:
137 		r = -EINVAL;
138 		break;
139 	}
140 
141 	return r;
142 }
143 
kvm_arm_default_max_vcpus(void)144 static int kvm_arm_default_max_vcpus(void)
145 {
146 	return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
147 }
148 
149 /**
150  * kvm_arch_init_vm - initializes a VM data structure
151  * @kvm:	pointer to the KVM struct
152  */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)153 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
154 {
155 	int ret;
156 
157 	if (type & ~KVM_VM_TYPE_MASK)
158 		return -EINVAL;
159 
160 	mutex_init(&kvm->arch.config_lock);
161 
162 #ifdef CONFIG_LOCKDEP
163 	/* Clue in lockdep that the config_lock must be taken inside kvm->lock */
164 	mutex_lock(&kvm->lock);
165 	mutex_lock(&kvm->arch.config_lock);
166 	mutex_unlock(&kvm->arch.config_lock);
167 	mutex_unlock(&kvm->lock);
168 #endif
169 
170 	ret = kvm_share_hyp(kvm, kvm + 1);
171 	if (ret)
172 		return ret;
173 
174 	ret = pkvm_init_host_vm(kvm, type);
175 	if (ret)
176 		goto err_unshare_kvm;
177 
178 	if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) {
179 		ret = -ENOMEM;
180 		goto err_unshare_kvm;
181 	}
182 	cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
183 
184 	ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
185 	if (ret)
186 		goto err_free_cpumask;
187 
188 	kvm_vgic_early_init(kvm);
189 
190 	kvm_timer_init_vm(kvm);
191 
192 	/* The maximum number of VCPUs is limited by the host's GIC model */
193 	kvm->max_vcpus = kvm_arm_default_max_vcpus();
194 
195 	kvm_arm_init_hypercalls(kvm);
196 
197 	bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
198 
199 	return 0;
200 
201 err_free_cpumask:
202 	free_cpumask_var(kvm->arch.supported_cpus);
203 err_unshare_kvm:
204 	kvm_unshare_hyp(kvm, kvm + 1);
205 	return ret;
206 }
207 
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)208 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
209 {
210 	return VM_FAULT_SIGBUS;
211 }
212 
213 
214 /**
215  * kvm_arch_destroy_vm - destroy the VM data structure
216  * @kvm:	pointer to the KVM struct
217  */
kvm_arch_destroy_vm(struct kvm * kvm)218 void kvm_arch_destroy_vm(struct kvm *kvm)
219 {
220 	kvm_uninit_stage2_mmu(kvm);
221 	bitmap_free(kvm->arch.pmu_filter);
222 	free_cpumask_var(kvm->arch.supported_cpus);
223 
224 	kvm_vgic_destroy(kvm);
225 
226 	if (is_protected_kvm_enabled())
227 		pkvm_destroy_hyp_vm(kvm);
228 
229 	kvm_destroy_vcpus(kvm);
230 
231 	kvm_unshare_hyp(kvm, kvm + 1);
232 
233 	kvm_arm_teardown_hypercalls(kvm);
234 
235 	if (atomic64_read(&kvm->stat.protected_hyp_mem))
236 		kvm_err("%lluB of donations to the nVHE hyp are missing\n",
237 			atomic64_read(&kvm->stat.protected_hyp_mem));
238 }
239 
kvm_check_extension(struct kvm * kvm,long ext)240 static int kvm_check_extension(struct kvm *kvm, long ext)
241 {
242 	int r;
243 
244 	switch (ext) {
245 	case KVM_CAP_IRQCHIP:
246 		r = vgic_present;
247 		break;
248 	case KVM_CAP_IOEVENTFD:
249 	case KVM_CAP_DEVICE_CTRL:
250 	case KVM_CAP_USER_MEMORY:
251 	case KVM_CAP_SYNC_MMU:
252 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
253 	case KVM_CAP_ONE_REG:
254 	case KVM_CAP_ARM_PSCI:
255 	case KVM_CAP_ARM_PSCI_0_2:
256 	case KVM_CAP_READONLY_MEM:
257 	case KVM_CAP_MP_STATE:
258 	case KVM_CAP_IMMEDIATE_EXIT:
259 	case KVM_CAP_VCPU_EVENTS:
260 	case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
261 	case KVM_CAP_ARM_INJECT_EXT_DABT:
262 	case KVM_CAP_SET_GUEST_DEBUG:
263 	case KVM_CAP_VCPU_ATTRIBUTES:
264 	case KVM_CAP_PTP_KVM:
265 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
266 	case KVM_CAP_IRQFD_RESAMPLE:
267 	case KVM_CAP_COUNTER_OFFSET:
268 		r = 1;
269 		break;
270 	case KVM_CAP_ARM_NISV_TO_USER:
271 		r = !kvm || !kvm_vm_is_protected(kvm);
272 		break;
273 	case KVM_CAP_SET_GUEST_DEBUG2:
274 		return KVM_GUESTDBG_VALID_MASK;
275 	case KVM_CAP_ARM_SET_DEVICE_ADDR:
276 		r = 1;
277 		break;
278 	case KVM_CAP_NR_VCPUS:
279 		/*
280 		 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
281 		 * architectures, as it does not always bound it to
282 		 * KVM_CAP_MAX_VCPUS. It should not matter much because
283 		 * this is just an advisory value.
284 		 */
285 		r = min_t(unsigned int, num_online_cpus(),
286 			  kvm_arm_default_max_vcpus());
287 		break;
288 	case KVM_CAP_MAX_VCPUS:
289 	case KVM_CAP_MAX_VCPU_ID:
290 		if (kvm)
291 			r = kvm->max_vcpus;
292 		else
293 			r = kvm_arm_default_max_vcpus();
294 		break;
295 	case KVM_CAP_MSI_DEVID:
296 		if (!kvm)
297 			r = -EINVAL;
298 		else
299 			r = kvm->arch.vgic.msis_require_devid;
300 		break;
301 	case KVM_CAP_ARM_USER_IRQ:
302 		/*
303 		 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
304 		 * (bump this number if adding more devices)
305 		 */
306 		r = 1;
307 		break;
308 	case KVM_CAP_ARM_MTE:
309 		r = system_supports_mte();
310 		break;
311 	case KVM_CAP_STEAL_TIME:
312 		r = kvm_arm_pvtime_supported();
313 		break;
314 	case KVM_CAP_ARM_EL1_32BIT:
315 		r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1);
316 		break;
317 	case KVM_CAP_GUEST_DEBUG_HW_BPS:
318 		r = get_num_brps();
319 		break;
320 	case KVM_CAP_GUEST_DEBUG_HW_WPS:
321 		r = get_num_wrps();
322 		break;
323 	case KVM_CAP_ARM_PMU_V3:
324 		r = kvm_arm_support_pmu_v3();
325 		break;
326 	case KVM_CAP_ARM_INJECT_SERROR_ESR:
327 		r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
328 		break;
329 	case KVM_CAP_ARM_VM_IPA_SIZE:
330 		r = get_kvm_ipa_limit();
331 		break;
332 	case KVM_CAP_ARM_SVE:
333 		r = system_supports_sve();
334 		break;
335 	case KVM_CAP_ARM_PTRAUTH_ADDRESS:
336 	case KVM_CAP_ARM_PTRAUTH_GENERIC:
337 		r = system_has_full_ptr_auth();
338 		break;
339 	case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
340 		if (kvm)
341 			r = kvm->arch.mmu.split_page_chunk_size;
342 		else
343 			r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT;
344 		break;
345 	case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES:
346 		r = kvm_supported_block_sizes();
347 		break;
348 	default:
349 		r = 0;
350 	}
351 
352 	return r;
353 }
354 
355 /*
356  * Checks whether the extension specified in ext is supported in protected
357  * mode for the specified vm.
358  * The capabilities supported by kvm in general are passed in kvm_cap.
359  */
pkvm_check_extension(struct kvm * kvm,long ext,int kvm_cap)360 static int pkvm_check_extension(struct kvm *kvm, long ext, int kvm_cap)
361 {
362 	int r;
363 
364 	switch (ext) {
365 	case KVM_CAP_IRQCHIP:
366 	case KVM_CAP_ARM_PSCI:
367 	case KVM_CAP_ARM_PSCI_0_2:
368 	case KVM_CAP_NR_VCPUS:
369 	case KVM_CAP_MAX_VCPUS:
370 	case KVM_CAP_MAX_VCPU_ID:
371 	case KVM_CAP_MSI_DEVID:
372 	case KVM_CAP_ARM_VM_IPA_SIZE:
373 		r = kvm_cap;
374 		break;
375 	case KVM_CAP_GUEST_DEBUG_HW_BPS:
376 		r = min(kvm_cap, pkvm_get_max_brps());
377 		break;
378 	case KVM_CAP_GUEST_DEBUG_HW_WPS:
379 		r = min(kvm_cap, pkvm_get_max_wrps());
380 		break;
381 	case KVM_CAP_ARM_PMU_V3:
382 		r = kvm_cap && FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer),
383 					 PVM_ID_AA64DFR0_ALLOW);
384 		break;
385 	case KVM_CAP_ARM_SVE:
386 		r = kvm_cap && FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_SVE),
387 					 PVM_ID_AA64PFR0_ALLOW);
388 		break;
389 	case KVM_CAP_ARM_PTRAUTH_ADDRESS:
390 		r = kvm_cap &&
391 		    FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_API),
392 			      PVM_ID_AA64ISAR1_ALLOW) &&
393 		    FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_APA),
394 			      PVM_ID_AA64ISAR1_ALLOW);
395 		break;
396 	case KVM_CAP_ARM_PTRAUTH_GENERIC:
397 		r = kvm_cap &&
398 		    FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_GPI),
399 			      PVM_ID_AA64ISAR1_ALLOW) &&
400 		    FIELD_GET(ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_GPA),
401 			      PVM_ID_AA64ISAR1_ALLOW);
402 		break;
403 	case KVM_CAP_ARM_PROTECTED_VM:
404 		r = 1;
405 		break;
406 	default:
407 		r = 0;
408 		break;
409 	}
410 
411 	return r;
412 }
413 
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)414 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
415 {
416 	int r = kvm_check_extension(kvm, ext);
417 
418 	if (kvm && kvm_vm_is_protected(kvm))
419 		r = pkvm_check_extension(kvm, ext, r);
420 
421 	return r;
422 }
423 
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)424 long kvm_arch_dev_ioctl(struct file *filp,
425 			unsigned int ioctl, unsigned long arg)
426 {
427 	return -EINVAL;
428 }
429 
kvm_arch_alloc_vm(void)430 struct kvm *kvm_arch_alloc_vm(void)
431 {
432 	size_t sz = sizeof(struct kvm);
433 
434 	if (!has_vhe())
435 		return kzalloc(sz, GFP_KERNEL_ACCOUNT);
436 
437 	return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
438 }
439 
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)440 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
441 {
442 	if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
443 		return -EBUSY;
444 
445 	if (id >= kvm->max_vcpus)
446 		return -EINVAL;
447 
448 	return 0;
449 }
450 
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)451 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
452 {
453 	int err;
454 
455 	spin_lock_init(&vcpu->arch.mp_state_lock);
456 
457 #ifdef CONFIG_LOCKDEP
458 	/* Inform lockdep that the config_lock is acquired after vcpu->mutex */
459 	mutex_lock(&vcpu->mutex);
460 	mutex_lock(&vcpu->kvm->arch.config_lock);
461 	mutex_unlock(&vcpu->kvm->arch.config_lock);
462 	mutex_unlock(&vcpu->mutex);
463 #endif
464 
465 	/* Force users to call KVM_ARM_VCPU_INIT */
466 	vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
467 	bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
468 
469 	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
470 
471 	/*
472 	 * Default value for the FP state, will be overloaded at load
473 	 * time if we support FP (pretty likely)
474 	 */
475 	vcpu->arch.fp_state = FP_STATE_FREE;
476 
477 	/* Set up the timer */
478 	kvm_timer_vcpu_init(vcpu);
479 
480 	kvm_pmu_vcpu_init(vcpu);
481 
482 	kvm_arm_reset_debug_ptr(vcpu);
483 
484 	kvm_arm_pvtime_vcpu_init(&vcpu->arch);
485 
486 	vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
487 
488 	err = kvm_vgic_vcpu_init(vcpu);
489 	if (err)
490 		return err;
491 
492 	return kvm_share_hyp(vcpu, vcpu + 1);
493 }
494 
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)495 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
496 {
497 }
498 
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)499 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
500 {
501 	if (vcpu_has_run_once(vcpu) && unlikely(!irqchip_in_kernel(vcpu->kvm)))
502 		static_branch_dec(&userspace_irqchip_in_use);
503 
504 	if (is_protected_kvm_enabled()) {
505 		atomic64_sub(vcpu->arch.stage2_mc.nr_pages << PAGE_SHIFT,
506 			     &vcpu->kvm->stat.protected_hyp_mem);
507 		free_hyp_memcache(&vcpu->arch.stage2_mc);
508 	} else {
509 		kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
510 	}
511 
512 	kvm_timer_vcpu_terminate(vcpu);
513 	kvm_pmu_vcpu_destroy(vcpu);
514 	kvm_vgic_vcpu_destroy(vcpu);
515 	kvm_arm_vcpu_destroy(vcpu);
516 }
517 
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)518 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
519 {
520 
521 }
522 
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)523 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
524 {
525 
526 }
527 
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)528 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
529 {
530 	struct kvm_s2_mmu *mmu;
531 	int *last_ran;
532 
533 	if (is_protected_kvm_enabled())
534 		goto nommu;
535 
536 	mmu = vcpu->arch.hw_mmu;
537 	last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
538 
539 	/*
540 	 * We guarantee that both TLBs and I-cache are private to each
541 	 * vcpu. If detecting that a vcpu from the same VM has
542 	 * previously run on the same physical CPU, call into the
543 	 * hypervisor code to nuke the relevant contexts.
544 	 *
545 	 * We might get preempted before the vCPU actually runs, but
546 	 * over-invalidation doesn't affect correctness.
547 	 */
548 	if (*last_ran != vcpu->vcpu_id) {
549 		kvm_call_hyp(__kvm_flush_cpu_context, mmu);
550 		*last_ran = vcpu->vcpu_id;
551 	}
552 
553 nommu:
554 	vcpu->cpu = cpu;
555 
556 	kvm_vgic_load(vcpu);
557 	kvm_timer_vcpu_load(vcpu);
558 	if (has_vhe())
559 		kvm_vcpu_load_sysregs_vhe(vcpu);
560 	kvm_arch_vcpu_load_fp(vcpu);
561 	kvm_vcpu_pmu_restore_guest(vcpu);
562 	if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
563 		kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
564 
565 	if (single_task_running())
566 		vcpu_clear_wfx_traps(vcpu);
567 	else
568 		vcpu_set_wfx_traps(vcpu);
569 
570 	if (vcpu_has_ptrauth(vcpu))
571 		vcpu_ptrauth_disable(vcpu);
572 	kvm_arch_vcpu_load_debug_state_flags(vcpu);
573 
574 	if (is_protected_kvm_enabled()) {
575 		kvm_call_hyp_nvhe(__pkvm_vcpu_load,
576 				  vcpu->kvm->arch.pkvm.handle,
577 				  vcpu->vcpu_idx, vcpu->arch.hcr_el2);
578 		kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
579 			     &vcpu->arch.vgic_cpu.vgic_v3);
580 	}
581 
582 	if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
583 		vcpu_set_on_unsupported_cpu(vcpu);
584 }
585 
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)586 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
587 {
588 	if (is_protected_kvm_enabled()) {
589 		kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
590 			     &vcpu->arch.vgic_cpu.vgic_v3);
591 		kvm_call_hyp_nvhe(__pkvm_vcpu_put);
592 
593 		/* __pkvm_vcpu_put implies a sync of the state */
594 		if (!kvm_vm_is_protected(vcpu->kvm))
595 			vcpu_set_flag(vcpu, PKVM_HOST_STATE_DIRTY);
596 	}
597 
598 	kvm_arch_vcpu_put_debug_state_flags(vcpu);
599 	kvm_arch_vcpu_put_fp(vcpu);
600 	if (has_vhe())
601 		kvm_vcpu_put_sysregs_vhe(vcpu);
602 	kvm_timer_vcpu_put(vcpu);
603 	kvm_vgic_put(vcpu);
604 	kvm_vcpu_pmu_restore_host(vcpu);
605 	kvm_arm_vmid_clear_active();
606 
607 	vcpu_clear_on_unsupported_cpu(vcpu);
608 	vcpu->cpu = -1;
609 }
610 
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)611 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
612 {
613 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
614 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
615 	kvm_vcpu_kick(vcpu);
616 }
617 
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)618 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
619 {
620 	spin_lock(&vcpu->arch.mp_state_lock);
621 	__kvm_arm_vcpu_power_off(vcpu);
622 	spin_unlock(&vcpu->arch.mp_state_lock);
623 }
624 
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)625 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
626 {
627 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
628 }
629 
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)630 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
631 {
632 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
633 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
634 	kvm_vcpu_kick(vcpu);
635 }
636 
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)637 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
638 {
639 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
640 }
641 
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)642 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
643 				    struct kvm_mp_state *mp_state)
644 {
645 	*mp_state = READ_ONCE(vcpu->arch.mp_state);
646 
647 	return 0;
648 }
649 
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)650 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
651 				    struct kvm_mp_state *mp_state)
652 {
653 	int ret = 0;
654 
655 	spin_lock(&vcpu->arch.mp_state_lock);
656 
657 	switch (mp_state->mp_state) {
658 	case KVM_MP_STATE_RUNNABLE:
659 		WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
660 		break;
661 	case KVM_MP_STATE_STOPPED:
662 		__kvm_arm_vcpu_power_off(vcpu);
663 		break;
664 	case KVM_MP_STATE_SUSPENDED:
665 		kvm_arm_vcpu_suspend(vcpu);
666 		break;
667 	default:
668 		ret = -EINVAL;
669 	}
670 
671 	spin_unlock(&vcpu->arch.mp_state_lock);
672 
673 	return ret;
674 }
675 
676 /**
677  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
678  * @v:		The VCPU pointer
679  *
680  * If the guest CPU is not waiting for interrupts or an interrupt line is
681  * asserted, the CPU is by definition runnable.
682  */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)683 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
684 {
685 	bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
686 	return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
687 		&& !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
688 }
689 
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)690 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
691 {
692 	return vcpu_mode_priv(vcpu);
693 }
694 
695 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)696 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
697 {
698 	return *vcpu_pc(vcpu);
699 }
700 #endif
701 
kvm_vcpu_initialized(struct kvm_vcpu * vcpu)702 static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu)
703 {
704 	return vcpu_get_flag(vcpu, VCPU_INITIALIZED);
705 }
706 
707 /*
708  * Handle both the initialisation that is being done when the vcpu is
709  * run for the first time, as well as the updates that must be
710  * performed each time we get a new thread dealing with this vcpu.
711  */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)712 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
713 {
714 	struct kvm *kvm = vcpu->kvm;
715 	int ret;
716 
717 	if (!kvm_vcpu_initialized(vcpu))
718 		return -ENOEXEC;
719 
720 	if (!kvm_arm_vcpu_is_finalized(vcpu))
721 		return -EPERM;
722 
723 	ret = kvm_arch_vcpu_run_map_fp(vcpu);
724 	if (ret)
725 		return ret;
726 
727 	if (likely(vcpu_has_run_once(vcpu)))
728 		return 0;
729 
730 	kvm_arm_vcpu_init_debug(vcpu);
731 
732 	if (likely(irqchip_in_kernel(kvm))) {
733 		/*
734 		 * Map the VGIC hardware resources before running a vcpu the
735 		 * first time on this VM.
736 		 */
737 		ret = kvm_vgic_map_resources(kvm);
738 		if (ret)
739 			return ret;
740 	}
741 
742 	ret = kvm_timer_enable(vcpu);
743 	if (ret)
744 		return ret;
745 
746 	ret = kvm_arm_pmu_v3_enable(vcpu);
747 	if (ret)
748 		return ret;
749 
750 	if (is_protected_kvm_enabled()) {
751 		/* Start with the vcpu in a dirty state */
752 		if (!kvm_vm_is_protected(vcpu->kvm))
753 			vcpu_set_flag(vcpu, PKVM_HOST_STATE_DIRTY);
754 		ret = pkvm_create_hyp_vm(kvm);
755 		if (ret)
756 			return ret;
757 	}
758 
759 	if (!irqchip_in_kernel(kvm)) {
760 		/*
761 		 * Tell the rest of the code that there are userspace irqchip
762 		 * VMs in the wild.
763 		 */
764 		static_branch_inc(&userspace_irqchip_in_use);
765 	}
766 
767 	mutex_lock(&kvm->arch.config_lock);
768 	set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
769 	mutex_unlock(&kvm->arch.config_lock);
770 
771 	return ret;
772 }
773 
kvm_arch_intc_initialized(struct kvm * kvm)774 bool kvm_arch_intc_initialized(struct kvm *kvm)
775 {
776 	return vgic_initialized(kvm);
777 }
778 
kvm_arm_halt_guest(struct kvm * kvm)779 void kvm_arm_halt_guest(struct kvm *kvm)
780 {
781 	unsigned long i;
782 	struct kvm_vcpu *vcpu;
783 
784 	kvm_for_each_vcpu(i, vcpu, kvm)
785 		vcpu->arch.pause = true;
786 	kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
787 }
788 
kvm_arm_resume_guest(struct kvm * kvm)789 void kvm_arm_resume_guest(struct kvm *kvm)
790 {
791 	unsigned long i;
792 	struct kvm_vcpu *vcpu;
793 
794 	kvm_for_each_vcpu(i, vcpu, kvm) {
795 		vcpu->arch.pause = false;
796 		__kvm_vcpu_wake_up(vcpu);
797 	}
798 }
799 
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)800 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
801 {
802 	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
803 
804 	rcuwait_wait_event(wait,
805 			   (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
806 			   TASK_INTERRUPTIBLE);
807 
808 	if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
809 		/* Awaken to handle a signal, request we sleep again later. */
810 		kvm_make_request(KVM_REQ_SLEEP, vcpu);
811 	}
812 
813 	/*
814 	 * Make sure we will observe a potential reset request if we've
815 	 * observed a change to the power state. Pairs with the smp_wmb() in
816 	 * kvm_psci_vcpu_on().
817 	 */
818 	smp_rmb();
819 }
820 
821 /**
822  * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
823  * @vcpu:	The VCPU pointer
824  *
825  * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
826  * the vCPU is runnable.  The vCPU may or may not be scheduled out, depending
827  * on when a wake event arrives, e.g. there may already be a pending wake event.
828  */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)829 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
830 {
831 	/*
832 	 * Sync back the state of the GIC CPU interface so that we have
833 	 * the latest PMR and group enables. This ensures that
834 	 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
835 	 * we have pending interrupts, e.g. when determining if the
836 	 * vCPU should block.
837 	 *
838 	 * For the same reason, we want to tell GICv4 that we need
839 	 * doorbells to be signalled, should an interrupt become pending.
840 	 */
841 	preempt_disable();
842 	vcpu_set_flag(vcpu, IN_WFI);
843 	kvm_vgic_put(vcpu);
844 	preempt_enable();
845 
846 	kvm_vcpu_halt(vcpu);
847 	vcpu_clear_flag(vcpu, IN_WFIT);
848 
849 	preempt_disable();
850 	vcpu_clear_flag(vcpu, IN_WFI);
851 	kvm_vgic_load(vcpu);
852 	preempt_enable();
853 }
854 
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)855 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
856 {
857 	if (!kvm_arm_vcpu_suspended(vcpu))
858 		return 1;
859 
860 	kvm_vcpu_wfi(vcpu);
861 
862 	/*
863 	 * The suspend state is sticky; we do not leave it until userspace
864 	 * explicitly marks the vCPU as runnable. Request that we suspend again
865 	 * later.
866 	 */
867 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
868 
869 	/*
870 	 * Check to make sure the vCPU is actually runnable. If so, exit to
871 	 * userspace informing it of the wakeup condition.
872 	 */
873 	if (kvm_arch_vcpu_runnable(vcpu)) {
874 		memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
875 		vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
876 		vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
877 		return 0;
878 	}
879 
880 	/*
881 	 * Otherwise, we were unblocked to process a different event, such as a
882 	 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
883 	 * process the event.
884 	 */
885 	return 1;
886 }
887 
888 /**
889  * check_vcpu_requests - check and handle pending vCPU requests
890  * @vcpu:	the VCPU pointer
891  *
892  * Return: 1 if we should enter the guest
893  *	   0 if we should exit to userspace
894  *	   < 0 if we should exit to userspace, where the return value indicates
895  *	   an error
896  */
check_vcpu_requests(struct kvm_vcpu * vcpu)897 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
898 {
899 	if (kvm_request_pending(vcpu)) {
900 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
901 			kvm_vcpu_sleep(vcpu);
902 
903 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
904 			kvm_reset_vcpu(vcpu);
905 
906 		/*
907 		 * Clear IRQ_PENDING requests that were made to guarantee
908 		 * that a VCPU sees new virtual interrupts.
909 		 */
910 		kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
911 
912 		if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
913 			kvm_update_stolen_time(vcpu);
914 
915 		if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
916 			/* The distributor enable bits were changed */
917 			preempt_disable();
918 			vgic_v4_put(vcpu);
919 			vgic_v4_load(vcpu);
920 			preempt_enable();
921 		}
922 
923 		if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
924 			kvm_pmu_handle_pmcr(vcpu,
925 					    __vcpu_sys_reg(vcpu, PMCR_EL0));
926 
927 		if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
928 			kvm_vcpu_pmu_restore_guest(vcpu);
929 
930 		if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
931 			return kvm_vcpu_suspend(vcpu);
932 
933 		if (kvm_dirty_ring_check_request(vcpu))
934 			return 0;
935 	}
936 
937 	return 1;
938 }
939 
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)940 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
941 {
942 	if (likely(!vcpu_mode_is_32bit(vcpu)))
943 		return false;
944 
945 	if (vcpu_has_nv(vcpu))
946 		return true;
947 
948 	return !kvm_supports_32bit_el0();
949 }
950 
951 /**
952  * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
953  * @vcpu:	The VCPU pointer
954  * @ret:	Pointer to write optional return code
955  *
956  * Returns: true if the VCPU needs to return to a preemptible + interruptible
957  *	    and skip guest entry.
958  *
959  * This function disambiguates between two different types of exits: exits to a
960  * preemptible + interruptible kernel context and exits to userspace. For an
961  * exit to userspace, this function will write the return code to ret and return
962  * true. For an exit to preemptible + interruptible kernel context (i.e. check
963  * for pending work and re-enter), return true without writing to ret.
964  */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)965 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
966 {
967 	struct kvm_run *run = vcpu->run;
968 
969 	/*
970 	 * If we're using a userspace irqchip, then check if we need
971 	 * to tell a userspace irqchip about timer or PMU level
972 	 * changes and if so, exit to userspace (the actual level
973 	 * state gets updated in kvm_timer_update_run and
974 	 * kvm_pmu_update_run below).
975 	 */
976 	if (static_branch_unlikely(&userspace_irqchip_in_use)) {
977 		if (kvm_timer_should_notify_user(vcpu) ||
978 		    kvm_pmu_should_notify_user(vcpu)) {
979 			*ret = -EINTR;
980 			run->exit_reason = KVM_EXIT_INTR;
981 			return true;
982 		}
983 	}
984 
985 	if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
986 		run->exit_reason = KVM_EXIT_FAIL_ENTRY;
987 		run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
988 		run->fail_entry.cpu = smp_processor_id();
989 		*ret = 0;
990 		return true;
991 	}
992 
993 	return kvm_request_pending(vcpu) ||
994 			xfer_to_guest_mode_work_pending();
995 }
996 
997 /*
998  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
999  * the vCPU is running.
1000  *
1001  * This must be noinstr as instrumentation may make use of RCU, and this is not
1002  * safe during the EQS.
1003  */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1004 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1005 {
1006 	int ret;
1007 
1008 	guest_state_enter_irqoff();
1009 	ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1010 	guest_state_exit_irqoff();
1011 
1012 	return ret;
1013 }
1014 
1015 /**
1016  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1017  * @vcpu:	The VCPU pointer
1018  *
1019  * This function is called through the VCPU_RUN ioctl called from user space. It
1020  * will execute VM code in a loop until the time slice for the process is used
1021  * or some emulation is needed from user space in which case the function will
1022  * return with return value 0 and with the kvm_run structure filled in with the
1023  * required data for the requested emulation.
1024  */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1025 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1026 {
1027 	struct kvm_run *run = vcpu->run;
1028 	int ret;
1029 
1030 	if (run->exit_reason == KVM_EXIT_MMIO) {
1031 		ret = kvm_handle_mmio_return(vcpu);
1032 		if (ret)
1033 			return ret;
1034 	}
1035 
1036 	vcpu_load(vcpu);
1037 
1038 	if (run->immediate_exit) {
1039 		ret = -EINTR;
1040 		goto out;
1041 	}
1042 
1043 	kvm_sigset_activate(vcpu);
1044 
1045 	ret = 1;
1046 	run->exit_reason = KVM_EXIT_UNKNOWN;
1047 	run->flags = 0;
1048 	while (ret > 0) {
1049 		/*
1050 		 * Check conditions before entering the guest
1051 		 */
1052 		ret = xfer_to_guest_mode_handle_work(vcpu);
1053 		if (!ret)
1054 			ret = 1;
1055 
1056 		if (ret > 0)
1057 			ret = check_vcpu_requests(vcpu);
1058 
1059 		/*
1060 		 * Preparing the interrupts to be injected also
1061 		 * involves poking the GIC, which must be done in a
1062 		 * non-preemptible context.
1063 		 */
1064 		preempt_disable();
1065 
1066 		/*
1067 		 * The VMID allocator only tracks active VMIDs per
1068 		 * physical CPU, and therefore the VMID allocated may not be
1069 		 * preserved on VMID roll-over if the task was preempted,
1070 		 * making a thread's VMID inactive. So we need to call
1071 		 * kvm_arm_vmid_update() in non-premptible context.
1072 		 */
1073 		kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid);
1074 
1075 		kvm_pmu_flush_hwstate(vcpu);
1076 
1077 		local_irq_disable();
1078 
1079 		kvm_vgic_flush_hwstate(vcpu);
1080 
1081 		kvm_pmu_update_vcpu_events(vcpu);
1082 
1083 		/*
1084 		 * Ensure we set mode to IN_GUEST_MODE after we disable
1085 		 * interrupts and before the final VCPU requests check.
1086 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
1087 		 * Documentation/virt/kvm/vcpu-requests.rst
1088 		 */
1089 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1090 
1091 		if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1092 			vcpu->mode = OUTSIDE_GUEST_MODE;
1093 			isb(); /* Ensure work in x_flush_hwstate is committed */
1094 			kvm_pmu_sync_hwstate(vcpu);
1095 			if (static_branch_unlikely(&userspace_irqchip_in_use))
1096 				kvm_timer_sync_user(vcpu);
1097 			kvm_vgic_sync_hwstate(vcpu);
1098 			local_irq_enable();
1099 			preempt_enable();
1100 			continue;
1101 		}
1102 
1103 		kvm_arm_setup_debug(vcpu);
1104 		kvm_arch_vcpu_ctxflush_fp(vcpu);
1105 
1106 		/**************************************************************
1107 		 * Enter the guest
1108 		 */
1109 		trace_kvm_entry(*vcpu_pc(vcpu));
1110 		guest_timing_enter_irqoff();
1111 
1112 		ret = kvm_arm_vcpu_enter_exit(vcpu);
1113 
1114 		vcpu->mode = OUTSIDE_GUEST_MODE;
1115 		vcpu->stat.exits++;
1116 		/*
1117 		 * Back from guest
1118 		 *************************************************************/
1119 
1120 		kvm_arm_clear_debug(vcpu);
1121 
1122 		/*
1123 		 * We must sync the PMU state before the vgic state so
1124 		 * that the vgic can properly sample the updated state of the
1125 		 * interrupt line.
1126 		 */
1127 		kvm_pmu_sync_hwstate(vcpu);
1128 
1129 		/*
1130 		 * Sync the vgic state before syncing the timer state because
1131 		 * the timer code needs to know if the virtual timer
1132 		 * interrupts are active.
1133 		 */
1134 		kvm_vgic_sync_hwstate(vcpu);
1135 
1136 		/*
1137 		 * Sync the timer hardware state before enabling interrupts as
1138 		 * we don't want vtimer interrupts to race with syncing the
1139 		 * timer virtual interrupt state.
1140 		 */
1141 		if (static_branch_unlikely(&userspace_irqchip_in_use))
1142 			kvm_timer_sync_user(vcpu);
1143 
1144 		kvm_arch_vcpu_ctxsync_fp(vcpu);
1145 
1146 		/*
1147 		 * We must ensure that any pending interrupts are taken before
1148 		 * we exit guest timing so that timer ticks are accounted as
1149 		 * guest time. Transiently unmask interrupts so that any
1150 		 * pending interrupts are taken.
1151 		 *
1152 		 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1153 		 * context synchronization event) is necessary to ensure that
1154 		 * pending interrupts are taken.
1155 		 */
1156 		if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1157 			local_irq_enable();
1158 			isb();
1159 			local_irq_disable();
1160 		}
1161 
1162 		guest_timing_exit_irqoff();
1163 
1164 		local_irq_enable();
1165 
1166 		trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1167 
1168 		/* Exit types that need handling before we can be preempted */
1169 		handle_exit_early(vcpu, ret);
1170 
1171 		preempt_enable();
1172 
1173 		/*
1174 		 * The ARMv8 architecture doesn't give the hypervisor
1175 		 * a mechanism to prevent a guest from dropping to AArch32 EL0
1176 		 * if implemented by the CPU. If we spot the guest in such
1177 		 * state and that we decided it wasn't supposed to do so (like
1178 		 * with the asymmetric AArch32 case), return to userspace with
1179 		 * a fatal error.
1180 		 */
1181 		if (vcpu_mode_is_bad_32bit(vcpu)) {
1182 			/*
1183 			 * As we have caught the guest red-handed, decide that
1184 			 * it isn't fit for purpose anymore by making the vcpu
1185 			 * invalid. The VMM can try and fix it by issuing  a
1186 			 * KVM_ARM_VCPU_INIT if it really wants to.
1187 			 */
1188 			vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1189 			ret = ARM_EXCEPTION_IL;
1190 		}
1191 
1192 		ret = handle_exit(vcpu, ret);
1193 	}
1194 
1195 	/* Tell userspace about in-kernel device output levels */
1196 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1197 		kvm_timer_update_run(vcpu);
1198 		kvm_pmu_update_run(vcpu);
1199 	}
1200 
1201 	kvm_sigset_deactivate(vcpu);
1202 
1203 out:
1204 	/*
1205 	 * In the unlikely event that we are returning to userspace
1206 	 * with pending exceptions or PC adjustment, commit these
1207 	 * adjustments in order to give userspace a consistent view of
1208 	 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1209 	 * being preempt-safe on VHE.
1210 	 */
1211 	if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1212 		     vcpu_get_flag(vcpu, INCREMENT_PC)))
1213 		kvm_call_hyp(__kvm_adjust_pc, vcpu);
1214 
1215 	vcpu_put(vcpu);
1216 	return ret;
1217 }
1218 
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1219 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1220 {
1221 	int bit_index;
1222 	bool set;
1223 	unsigned long *hcr;
1224 
1225 	if (number == KVM_ARM_IRQ_CPU_IRQ)
1226 		bit_index = __ffs(HCR_VI);
1227 	else /* KVM_ARM_IRQ_CPU_FIQ */
1228 		bit_index = __ffs(HCR_VF);
1229 
1230 	hcr = vcpu_hcr(vcpu);
1231 	if (level)
1232 		set = test_and_set_bit(bit_index, hcr);
1233 	else
1234 		set = test_and_clear_bit(bit_index, hcr);
1235 
1236 	/*
1237 	 * If we didn't change anything, no need to wake up or kick other CPUs
1238 	 */
1239 	if (set == level)
1240 		return 0;
1241 
1242 	/*
1243 	 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1244 	 * trigger a world-switch round on the running physical CPU to set the
1245 	 * virtual IRQ/FIQ fields in the HCR appropriately.
1246 	 */
1247 	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1248 	kvm_vcpu_kick(vcpu);
1249 
1250 	return 0;
1251 }
1252 
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1253 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1254 			  bool line_status)
1255 {
1256 	u32 irq = irq_level->irq;
1257 	unsigned int irq_type, vcpu_idx, irq_num;
1258 	int nrcpus = atomic_read(&kvm->online_vcpus);
1259 	struct kvm_vcpu *vcpu = NULL;
1260 	bool level = irq_level->level;
1261 
1262 	irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1263 	vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1264 	vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1265 	irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1266 
1267 	trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
1268 
1269 	switch (irq_type) {
1270 	case KVM_ARM_IRQ_TYPE_CPU:
1271 		if (irqchip_in_kernel(kvm))
1272 			return -ENXIO;
1273 
1274 		if (vcpu_idx >= nrcpus)
1275 			return -EINVAL;
1276 
1277 		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1278 		if (!vcpu)
1279 			return -EINVAL;
1280 
1281 		if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1282 			return -EINVAL;
1283 
1284 		return vcpu_interrupt_line(vcpu, irq_num, level);
1285 	case KVM_ARM_IRQ_TYPE_PPI:
1286 		if (!irqchip_in_kernel(kvm))
1287 			return -ENXIO;
1288 
1289 		if (vcpu_idx >= nrcpus)
1290 			return -EINVAL;
1291 
1292 		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
1293 		if (!vcpu)
1294 			return -EINVAL;
1295 
1296 		if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1297 			return -EINVAL;
1298 
1299 		return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
1300 	case KVM_ARM_IRQ_TYPE_SPI:
1301 		if (!irqchip_in_kernel(kvm))
1302 			return -ENXIO;
1303 
1304 		if (irq_num < VGIC_NR_PRIVATE_IRQS)
1305 			return -EINVAL;
1306 
1307 		return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
1308 	}
1309 
1310 	return -EINVAL;
1311 }
1312 
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1313 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1314 					const struct kvm_vcpu_init *init)
1315 {
1316 	unsigned long features = init->features[0];
1317 	int i;
1318 
1319 	if (features & ~KVM_VCPU_VALID_FEATURES)
1320 		return -ENOENT;
1321 
1322 	for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1323 		if (init->features[i])
1324 			return -ENOENT;
1325 	}
1326 
1327 	if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1328 		return 0;
1329 
1330 	if (!cpus_have_const_cap(ARM64_HAS_32BIT_EL1))
1331 		return -EINVAL;
1332 
1333 	/* MTE is incompatible with AArch32 */
1334 	if (kvm_has_mte(vcpu->kvm))
1335 		return -EINVAL;
1336 
1337 	/* NV is incompatible with AArch32 */
1338 	if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1339 		return -EINVAL;
1340 
1341 	return 0;
1342 }
1343 
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1344 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1345 				  const struct kvm_vcpu_init *init)
1346 {
1347 	unsigned long features = init->features[0];
1348 
1349 	return !bitmap_equal(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES);
1350 }
1351 
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1352 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1353 				 const struct kvm_vcpu_init *init)
1354 {
1355 	unsigned long features = init->features[0];
1356 	struct kvm *kvm = vcpu->kvm;
1357 	int ret = -EINVAL;
1358 
1359 	mutex_lock(&kvm->arch.config_lock);
1360 
1361 	if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1362 	    !bitmap_equal(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES))
1363 		goto out_unlock;
1364 
1365 	bitmap_copy(vcpu->arch.features, &features, KVM_VCPU_MAX_FEATURES);
1366 
1367 	/* Now we know what it is, we can reset it. */
1368 	ret = kvm_reset_vcpu(vcpu);
1369 	if (ret) {
1370 		bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
1371 		goto out_unlock;
1372 	}
1373 
1374 	bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1375 	set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1376 	vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1377 out_unlock:
1378 	mutex_unlock(&kvm->arch.config_lock);
1379 	return ret;
1380 }
1381 
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1382 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1383 			       const struct kvm_vcpu_init *init)
1384 {
1385 	int ret;
1386 
1387 	if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1388 	    init->target != kvm_target_cpu())
1389 		return -EINVAL;
1390 
1391 	ret = kvm_vcpu_init_check_features(vcpu, init);
1392 	if (ret)
1393 		return ret;
1394 
1395 	if (!kvm_vcpu_initialized(vcpu))
1396 		return __kvm_vcpu_set_target(vcpu, init);
1397 
1398 	if (kvm_vcpu_init_changed(vcpu, init))
1399 		return -EINVAL;
1400 
1401 	return kvm_reset_vcpu(vcpu);
1402 }
1403 
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1404 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1405 					 struct kvm_vcpu_init *init)
1406 {
1407 	bool power_off = false;
1408 	int ret;
1409 
1410 	/*
1411 	 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1412 	 * reflecting it in the finalized feature set, thus limiting its scope
1413 	 * to a single KVM_ARM_VCPU_INIT call.
1414 	 */
1415 	if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1416 		init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1417 		power_off = true;
1418 	}
1419 
1420 	ret = kvm_vcpu_set_target(vcpu, init);
1421 	if (ret)
1422 		return ret;
1423 
1424 	/*
1425 	 * Ensure a rebooted VM will fault in RAM pages and detect if the
1426 	 * guest MMU is turned off and flush the caches as needed.
1427 	 *
1428 	 * S2FWB enforces all memory accesses to RAM being cacheable,
1429 	 * ensuring that the data side is always coherent. We still
1430 	 * need to invalidate the I-cache though, as FWB does *not*
1431 	 * imply CTR_EL0.DIC.
1432 	 */
1433 	if (vcpu_has_run_once(vcpu)) {
1434 		if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1435 			stage2_unmap_vm(vcpu->kvm);
1436 		else
1437 			icache_inval_all_pou();
1438 	}
1439 
1440 	vcpu_reset_hcr(vcpu);
1441 	vcpu->arch.cptr_el2 = kvm_get_reset_cptr_el2(vcpu);
1442 
1443 	/*
1444 	 * Handle the "start in power-off" case.
1445 	 */
1446 	spin_lock(&vcpu->arch.mp_state_lock);
1447 
1448 	if (power_off)
1449 		__kvm_arm_vcpu_power_off(vcpu);
1450 	else
1451 		WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1452 
1453 	spin_unlock(&vcpu->arch.mp_state_lock);
1454 
1455 	return 0;
1456 }
1457 
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1458 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1459 				 struct kvm_device_attr *attr)
1460 {
1461 	int ret = -ENXIO;
1462 
1463 	switch (attr->group) {
1464 	default:
1465 		ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1466 		break;
1467 	}
1468 
1469 	return ret;
1470 }
1471 
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1472 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1473 				 struct kvm_device_attr *attr)
1474 {
1475 	int ret = -ENXIO;
1476 
1477 	switch (attr->group) {
1478 	default:
1479 		ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1480 		break;
1481 	}
1482 
1483 	return ret;
1484 }
1485 
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1486 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1487 				 struct kvm_device_attr *attr)
1488 {
1489 	int ret = -ENXIO;
1490 
1491 	switch (attr->group) {
1492 	default:
1493 		ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1494 		break;
1495 	}
1496 
1497 	return ret;
1498 }
1499 
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1500 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1501 				   struct kvm_vcpu_events *events)
1502 {
1503 	memset(events, 0, sizeof(*events));
1504 
1505 	return __kvm_arm_vcpu_get_events(vcpu, events);
1506 }
1507 
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1508 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1509 				   struct kvm_vcpu_events *events)
1510 {
1511 	int i;
1512 
1513 	/* check whether the reserved field is zero */
1514 	for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1515 		if (events->reserved[i])
1516 			return -EINVAL;
1517 
1518 	/* check whether the pad field is zero */
1519 	for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1520 		if (events->exception.pad[i])
1521 			return -EINVAL;
1522 
1523 	return __kvm_arm_vcpu_set_events(vcpu, events);
1524 }
1525 
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1526 long kvm_arch_vcpu_ioctl(struct file *filp,
1527 			 unsigned int ioctl, unsigned long arg)
1528 {
1529 	struct kvm_vcpu *vcpu = filp->private_data;
1530 	void __user *argp = (void __user *)arg;
1531 	struct kvm_device_attr attr;
1532 	long r;
1533 
1534 	switch (ioctl) {
1535 	case KVM_ARM_VCPU_INIT: {
1536 		struct kvm_vcpu_init init;
1537 
1538 		r = -EFAULT;
1539 		if (copy_from_user(&init, argp, sizeof(init)))
1540 			break;
1541 
1542 		r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1543 		break;
1544 	}
1545 	case KVM_SET_ONE_REG:
1546 	case KVM_GET_ONE_REG: {
1547 		struct kvm_one_reg reg;
1548 
1549 		r = -ENOEXEC;
1550 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1551 			break;
1552 
1553 		r = -EFAULT;
1554 		if (copy_from_user(&reg, argp, sizeof(reg)))
1555 			break;
1556 
1557 		/*
1558 		 * We could owe a reset due to PSCI. Handle the pending reset
1559 		 * here to ensure userspace register accesses are ordered after
1560 		 * the reset.
1561 		 */
1562 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1563 			kvm_reset_vcpu(vcpu);
1564 
1565 		if (ioctl == KVM_SET_ONE_REG)
1566 			r = kvm_arm_set_reg(vcpu, &reg);
1567 		else
1568 			r = kvm_arm_get_reg(vcpu, &reg);
1569 		break;
1570 	}
1571 	case KVM_GET_REG_LIST: {
1572 		struct kvm_reg_list __user *user_list = argp;
1573 		struct kvm_reg_list reg_list;
1574 		unsigned n;
1575 
1576 		r = -ENOEXEC;
1577 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1578 			break;
1579 
1580 		r = -EPERM;
1581 		if (!kvm_arm_vcpu_is_finalized(vcpu))
1582 			break;
1583 
1584 		r = -EFAULT;
1585 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1586 			break;
1587 		n = reg_list.n;
1588 		reg_list.n = kvm_arm_num_regs(vcpu);
1589 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1590 			break;
1591 		r = -E2BIG;
1592 		if (n < reg_list.n)
1593 			break;
1594 		r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1595 		break;
1596 	}
1597 	case KVM_SET_DEVICE_ATTR: {
1598 		r = -EFAULT;
1599 		if (copy_from_user(&attr, argp, sizeof(attr)))
1600 			break;
1601 		r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1602 		break;
1603 	}
1604 	case KVM_GET_DEVICE_ATTR: {
1605 		r = -EFAULT;
1606 		if (copy_from_user(&attr, argp, sizeof(attr)))
1607 			break;
1608 		r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1609 		break;
1610 	}
1611 	case KVM_HAS_DEVICE_ATTR: {
1612 		r = -EFAULT;
1613 		if (copy_from_user(&attr, argp, sizeof(attr)))
1614 			break;
1615 		r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1616 		break;
1617 	}
1618 	case KVM_GET_VCPU_EVENTS: {
1619 		struct kvm_vcpu_events events;
1620 
1621 		if (kvm_arm_vcpu_get_events(vcpu, &events))
1622 			return -EINVAL;
1623 
1624 		if (copy_to_user(argp, &events, sizeof(events)))
1625 			return -EFAULT;
1626 
1627 		return 0;
1628 	}
1629 	case KVM_SET_VCPU_EVENTS: {
1630 		struct kvm_vcpu_events events;
1631 
1632 		if (copy_from_user(&events, argp, sizeof(events)))
1633 			return -EFAULT;
1634 
1635 		return kvm_arm_vcpu_set_events(vcpu, &events);
1636 	}
1637 	case KVM_ARM_VCPU_FINALIZE: {
1638 		int what;
1639 
1640 		if (!kvm_vcpu_initialized(vcpu))
1641 			return -ENOEXEC;
1642 
1643 		if (get_user(what, (const int __user *)argp))
1644 			return -EFAULT;
1645 
1646 		return kvm_arm_vcpu_finalize(vcpu, what);
1647 	}
1648 	default:
1649 		r = -EINVAL;
1650 	}
1651 
1652 	return r;
1653 }
1654 
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1655 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1656 {
1657 
1658 }
1659 
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1660 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1661 					struct kvm_arm_device_addr *dev_addr)
1662 {
1663 	switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1664 	case KVM_ARM_DEVICE_VGIC_V2:
1665 		if (!vgic_present)
1666 			return -ENXIO;
1667 		return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1668 	default:
1669 		return -ENODEV;
1670 	}
1671 }
1672 
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1673 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1674 {
1675 	switch (attr->group) {
1676 	case KVM_ARM_VM_SMCCC_CTRL:
1677 		return kvm_vm_smccc_has_attr(kvm, attr);
1678 	default:
1679 		return -ENXIO;
1680 	}
1681 }
1682 
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1683 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1684 {
1685 	switch (attr->group) {
1686 	case KVM_ARM_VM_SMCCC_CTRL:
1687 		return kvm_vm_smccc_set_attr(kvm, attr);
1688 	default:
1689 		return -ENXIO;
1690 	}
1691 }
1692 
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1693 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1694 {
1695 	struct kvm *kvm = filp->private_data;
1696 	void __user *argp = (void __user *)arg;
1697 	struct kvm_device_attr attr;
1698 
1699 	switch (ioctl) {
1700 	case KVM_CREATE_IRQCHIP: {
1701 		int ret;
1702 		if (!vgic_present)
1703 			return -ENXIO;
1704 		mutex_lock(&kvm->lock);
1705 		ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1706 		mutex_unlock(&kvm->lock);
1707 		return ret;
1708 	}
1709 	case KVM_ARM_SET_DEVICE_ADDR: {
1710 		struct kvm_arm_device_addr dev_addr;
1711 
1712 		if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1713 			return -EFAULT;
1714 		return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1715 	}
1716 	case KVM_ARM_PREFERRED_TARGET: {
1717 		struct kvm_vcpu_init init = {
1718 			.target = KVM_ARM_TARGET_GENERIC_V8,
1719 		};
1720 
1721 		if (copy_to_user(argp, &init, sizeof(init)))
1722 			return -EFAULT;
1723 
1724 		return 0;
1725 	}
1726 	case KVM_ARM_MTE_COPY_TAGS: {
1727 		struct kvm_arm_copy_mte_tags copy_tags;
1728 
1729 		if (copy_from_user(&copy_tags, argp, sizeof(copy_tags)))
1730 			return -EFAULT;
1731 		return kvm_vm_ioctl_mte_copy_tags(kvm, &copy_tags);
1732 	}
1733 	case KVM_ARM_SET_COUNTER_OFFSET: {
1734 		struct kvm_arm_counter_offset offset;
1735 
1736 		if (copy_from_user(&offset, argp, sizeof(offset)))
1737 			return -EFAULT;
1738 		return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1739 	}
1740 	case KVM_HAS_DEVICE_ATTR: {
1741 		if (copy_from_user(&attr, argp, sizeof(attr)))
1742 			return -EFAULT;
1743 
1744 		return kvm_vm_has_attr(kvm, &attr);
1745 	}
1746 	case KVM_SET_DEVICE_ATTR: {
1747 		if (copy_from_user(&attr, argp, sizeof(attr)))
1748 			return -EFAULT;
1749 
1750 		return kvm_vm_set_attr(kvm, &attr);
1751 	}
1752 	default:
1753 		return -EINVAL;
1754 	}
1755 }
1756 
1757 /* unlocks vcpus from @vcpu_lock_idx and smaller */
unlock_vcpus(struct kvm * kvm,int vcpu_lock_idx)1758 static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
1759 {
1760 	struct kvm_vcpu *tmp_vcpu;
1761 
1762 	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
1763 		tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
1764 		mutex_unlock(&tmp_vcpu->mutex);
1765 	}
1766 }
1767 
unlock_all_vcpus(struct kvm * kvm)1768 void unlock_all_vcpus(struct kvm *kvm)
1769 {
1770 	lockdep_assert_held(&kvm->lock);
1771 
1772 	unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
1773 }
1774 
1775 /* Returns true if all vcpus were locked, false otherwise */
lock_all_vcpus(struct kvm * kvm)1776 bool lock_all_vcpus(struct kvm *kvm)
1777 {
1778 	struct kvm_vcpu *tmp_vcpu;
1779 	unsigned long c;
1780 
1781 	lockdep_assert_held(&kvm->lock);
1782 
1783 	/*
1784 	 * Any time a vcpu is in an ioctl (including running), the
1785 	 * core KVM code tries to grab the vcpu->mutex.
1786 	 *
1787 	 * By grabbing the vcpu->mutex of all VCPUs we ensure that no
1788 	 * other VCPUs can fiddle with the state while we access it.
1789 	 */
1790 	kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
1791 		if (!mutex_trylock(&tmp_vcpu->mutex)) {
1792 			unlock_vcpus(kvm, c - 1);
1793 			return false;
1794 		}
1795 	}
1796 
1797 	return true;
1798 }
1799 
nvhe_percpu_size(void)1800 static unsigned long nvhe_percpu_size(void)
1801 {
1802 	return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1803 		(unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1804 }
1805 
nvhe_percpu_order(void)1806 static unsigned long nvhe_percpu_order(void)
1807 {
1808 	unsigned long size = nvhe_percpu_size();
1809 
1810 	return size ? get_order(size) : 0;
1811 }
1812 
pkvm_host_fp_state_order(void)1813 static inline size_t pkvm_host_fp_state_order(void)
1814 {
1815 	return get_order(pkvm_host_fp_state_size());
1816 }
1817 
1818 /* A lookup table holding the hypervisor VA for each vector slot */
1819 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1820 
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1821 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1822 {
1823 	hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1824 }
1825 
kvm_init_vector_slots(void)1826 static int kvm_init_vector_slots(void)
1827 {
1828 	int err;
1829 	void *base;
1830 
1831 	base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1832 	kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1833 
1834 	base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1835 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1836 
1837 	if (kvm_system_needs_idmapped_vectors() &&
1838 	    !is_protected_kvm_enabled()) {
1839 		err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1840 					       __BP_HARDEN_HYP_VECS_SZ, &base);
1841 		if (err)
1842 			return err;
1843 	}
1844 
1845 	kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1846 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1847 	return 0;
1848 }
1849 
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1850 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1851 {
1852 	struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1853 	unsigned long tcr;
1854 	int *hyp_cpu_number_ptr = per_cpu_ptr_nvhe_sym(hyp_cpu_number, cpu);
1855 
1856 	*hyp_cpu_number_ptr = cpu;
1857 
1858 	/*
1859 	 * Calculate the raw per-cpu offset without a translation from the
1860 	 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1861 	 * so that we can use adr_l to access per-cpu variables in EL2.
1862 	 * Also drop the KASAN tag which gets in the way...
1863 	 */
1864 	params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1865 			    (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1866 
1867 	params->mair_el2 = read_sysreg(mair_el1);
1868 
1869 	tcr = read_sysreg(tcr_el1);
1870 	if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
1871 		tcr |= TCR_EPD1_MASK;
1872 	} else {
1873 		tcr &= TCR_EL2_MASK;
1874 		tcr |= TCR_EL2_RES1;
1875 	}
1876 	tcr &= ~TCR_T0SZ_MASK;
1877 	tcr |= TCR_T0SZ(hyp_va_bits);
1878 	params->tcr_el2 = tcr;
1879 
1880 	params->pgd_pa = kvm_mmu_get_httbr();
1881 	if (is_protected_kvm_enabled())
1882 		params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
1883 	else
1884 		params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
1885 	if (cpus_have_final_cap(ARM64_KVM_HVHE))
1886 		params->hcr_el2 |= HCR_E2H;
1887 	params->vttbr = params->vtcr = 0;
1888 	params->hfgwtr_el2 = HFGxTR_EL2_nSMPRI_EL1_MASK | HFGxTR_EL2_nTPIDR2_EL0_MASK;
1889 
1890 	/*
1891 	 * Flush the init params from the data cache because the struct will
1892 	 * be read while the MMU is off.
1893 	 */
1894 	kvm_flush_dcache_to_poc(params, sizeof(*params));
1895 }
1896 
hyp_install_host_vector(void)1897 static void hyp_install_host_vector(void)
1898 {
1899 	struct kvm_nvhe_init_params *params;
1900 	struct arm_smccc_res res;
1901 
1902 	/* Switch from the HYP stub to our own HYP init vector */
1903 	__hyp_set_vectors(kvm_get_idmap_vector());
1904 
1905 	/*
1906 	 * Call initialization code, and switch to the full blown HYP code.
1907 	 * If the cpucaps haven't been finalized yet, something has gone very
1908 	 * wrong, and hyp will crash and burn when it uses any
1909 	 * cpus_have_const_cap() wrapper.
1910 	 */
1911 	BUG_ON(!system_capabilities_finalized());
1912 	params = this_cpu_ptr_nvhe_sym(kvm_init_params);
1913 	arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
1914 	WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
1915 }
1916 
cpu_init_hyp_mode(void)1917 static void cpu_init_hyp_mode(void)
1918 {
1919 	hyp_install_host_vector();
1920 
1921 	/*
1922 	 * Disabling SSBD on a non-VHE system requires us to enable SSBS
1923 	 * at EL2.
1924 	 */
1925 	if (this_cpu_has_cap(ARM64_SSBS) &&
1926 	    arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
1927 		kvm_call_hyp_nvhe(__kvm_enable_ssbs);
1928 	}
1929 }
1930 
cpu_hyp_reset(void)1931 static void cpu_hyp_reset(void)
1932 {
1933 	if (!is_kernel_in_hyp_mode())
1934 		__hyp_reset_vectors();
1935 }
1936 
1937 /*
1938  * EL2 vectors can be mapped and rerouted in a number of ways,
1939  * depending on the kernel configuration and CPU present:
1940  *
1941  * - If the CPU is affected by Spectre-v2, the hardening sequence is
1942  *   placed in one of the vector slots, which is executed before jumping
1943  *   to the real vectors.
1944  *
1945  * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
1946  *   containing the hardening sequence is mapped next to the idmap page,
1947  *   and executed before jumping to the real vectors.
1948  *
1949  * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
1950  *   empty slot is selected, mapped next to the idmap page, and
1951  *   executed before jumping to the real vectors.
1952  *
1953  * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
1954  * VHE, as we don't have hypervisor-specific mappings. If the system
1955  * is VHE and yet selects this capability, it will be ignored.
1956  */
cpu_set_hyp_vector(void)1957 static void cpu_set_hyp_vector(void)
1958 {
1959 	struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
1960 	void *vector = hyp_spectre_vector_selector[data->slot];
1961 
1962 	if (!is_protected_kvm_enabled())
1963 		*this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
1964 	else
1965 		kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
1966 }
1967 
cpu_hyp_init_context(void)1968 static void cpu_hyp_init_context(void)
1969 {
1970 	kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt);
1971 
1972 	if (!is_kernel_in_hyp_mode())
1973 		cpu_init_hyp_mode();
1974 }
1975 
cpu_hyp_init_features(void)1976 static void cpu_hyp_init_features(void)
1977 {
1978 	cpu_set_hyp_vector();
1979 	kvm_arm_init_debug();
1980 
1981 	if (is_kernel_in_hyp_mode())
1982 		kvm_timer_init_vhe();
1983 
1984 	if (vgic_present)
1985 		kvm_vgic_init_cpu_hardware();
1986 }
1987 
cpu_hyp_reinit(void)1988 static void cpu_hyp_reinit(void)
1989 {
1990 	cpu_hyp_reset();
1991 	cpu_hyp_init_context();
1992 	cpu_hyp_init_features();
1993 }
1994 
cpu_hyp_init(void * discard)1995 static void cpu_hyp_init(void *discard)
1996 {
1997 	if (!__this_cpu_read(kvm_hyp_initialized)) {
1998 		cpu_hyp_reinit();
1999 		__this_cpu_write(kvm_hyp_initialized, 1);
2000 	}
2001 }
2002 
cpu_hyp_uninit(void * discard)2003 static void cpu_hyp_uninit(void *discard)
2004 {
2005 	if (__this_cpu_read(kvm_hyp_initialized)) {
2006 		cpu_hyp_reset();
2007 		__this_cpu_write(kvm_hyp_initialized, 0);
2008 	}
2009 }
2010 
kvm_arch_hardware_enable(void)2011 int kvm_arch_hardware_enable(void)
2012 {
2013 	/*
2014 	 * Most calls to this function are made with migration
2015 	 * disabled, but not with preemption disabled. The former is
2016 	 * enough to ensure correctness, but most of the helpers
2017 	 * expect the later and will throw a tantrum otherwise.
2018 	 */
2019 	preempt_disable();
2020 
2021 	cpu_hyp_init(NULL);
2022 
2023 	kvm_vgic_cpu_up();
2024 	kvm_timer_cpu_up();
2025 
2026 	preempt_enable();
2027 
2028 	return 0;
2029 }
2030 
kvm_arch_hardware_disable(void)2031 void kvm_arch_hardware_disable(void)
2032 {
2033 	kvm_timer_cpu_down();
2034 	kvm_vgic_cpu_down();
2035 
2036 	if (!is_protected_kvm_enabled())
2037 		cpu_hyp_uninit(NULL);
2038 }
2039 
2040 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2041 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2042 				    unsigned long cmd,
2043 				    void *v)
2044 {
2045 	/*
2046 	 * kvm_hyp_initialized is left with its old value over
2047 	 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2048 	 * re-enable hyp.
2049 	 */
2050 	switch (cmd) {
2051 	case CPU_PM_ENTER:
2052 		if (__this_cpu_read(kvm_hyp_initialized))
2053 			/*
2054 			 * don't update kvm_hyp_initialized here
2055 			 * so that the hyp will be re-enabled
2056 			 * when we resume. See below.
2057 			 */
2058 			cpu_hyp_reset();
2059 
2060 		return NOTIFY_OK;
2061 	case CPU_PM_ENTER_FAILED:
2062 	case CPU_PM_EXIT:
2063 		if (__this_cpu_read(kvm_hyp_initialized))
2064 			/* The hyp was enabled before suspend. */
2065 			cpu_hyp_reinit();
2066 
2067 		return NOTIFY_OK;
2068 
2069 	default:
2070 		return NOTIFY_DONE;
2071 	}
2072 }
2073 
2074 static struct notifier_block hyp_init_cpu_pm_nb = {
2075 	.notifier_call = hyp_init_cpu_pm_notifier,
2076 };
2077 
hyp_cpu_pm_init(void)2078 static void __init hyp_cpu_pm_init(void)
2079 {
2080 	if (!is_protected_kvm_enabled())
2081 		cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2082 }
hyp_cpu_pm_exit(void)2083 static void __init hyp_cpu_pm_exit(void)
2084 {
2085 	if (!is_protected_kvm_enabled())
2086 		cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2087 }
2088 #else
hyp_cpu_pm_init(void)2089 static inline void __init hyp_cpu_pm_init(void)
2090 {
2091 }
hyp_cpu_pm_exit(void)2092 static inline void __init hyp_cpu_pm_exit(void)
2093 {
2094 }
2095 #endif
2096 
init_cpu_logical_map(void)2097 static void __init init_cpu_logical_map(void)
2098 {
2099 	unsigned int cpu;
2100 
2101 	/*
2102 	 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2103 	 * Only copy the set of online CPUs whose features have been checked
2104 	 * against the finalized system capabilities. The hypervisor will not
2105 	 * allow any other CPUs from the `possible` set to boot.
2106 	 */
2107 	for_each_online_cpu(cpu)
2108 		hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2109 }
2110 
2111 #define init_psci_0_1_impl_state(config, what)	\
2112 	config.psci_0_1_ ## what ## _implemented = psci_ops.what
2113 
init_psci_relay(void)2114 static bool __init init_psci_relay(void)
2115 {
2116 	/*
2117 	 * If PSCI has not been initialized, protected KVM cannot install
2118 	 * itself on newly booted CPUs.
2119 	 */
2120 	if (!psci_ops.get_version) {
2121 		kvm_err("Cannot initialize protected mode without PSCI\n");
2122 		return false;
2123 	}
2124 
2125 	kvm_host_psci_config.version = psci_ops.get_version();
2126 	kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2127 
2128 	if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2129 		kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2130 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2131 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2132 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2133 		init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2134 	}
2135 	return true;
2136 }
2137 
init_subsystems(void)2138 static int __init init_subsystems(void)
2139 {
2140 	int err = 0;
2141 
2142 	/*
2143 	 * Enable hardware so that subsystem initialisation can access EL2.
2144 	 */
2145 	on_each_cpu(cpu_hyp_init, NULL, 1);
2146 
2147 	/*
2148 	 * Register CPU lower-power notifier
2149 	 */
2150 	hyp_cpu_pm_init();
2151 
2152 	/*
2153 	 * Init HYP view of VGIC
2154 	 */
2155 	err = kvm_vgic_hyp_init();
2156 	switch (err) {
2157 	case 0:
2158 		vgic_present = true;
2159 		break;
2160 	case -ENODEV:
2161 	case -ENXIO:
2162 		vgic_present = false;
2163 		err = 0;
2164 		break;
2165 	default:
2166 		goto out;
2167 	}
2168 
2169 	/*
2170 	 * Init HYP architected timer support
2171 	 */
2172 	err = kvm_timer_hyp_init(vgic_present);
2173 	if (err)
2174 		goto out;
2175 
2176 	kvm_register_perf_callbacks(NULL);
2177 
2178 	err = hyp_trace_init_tracefs();
2179 	if (err)
2180 		kvm_err("Failed to initialize Hyp tracing\n");
2181 out:
2182 	if (err)
2183 		hyp_cpu_pm_exit();
2184 
2185 	if (err || !is_protected_kvm_enabled())
2186 		on_each_cpu(cpu_hyp_uninit, NULL, 1);
2187 
2188 	return err;
2189 }
2190 
teardown_subsystems(void)2191 static void __init teardown_subsystems(void)
2192 {
2193 	kvm_unregister_perf_callbacks();
2194 	hyp_cpu_pm_exit();
2195 }
2196 
teardown_hyp_mode(void)2197 static void __init teardown_hyp_mode(void)
2198 {
2199 	int cpu;
2200 
2201 	free_hyp_pgds();
2202 	for_each_possible_cpu(cpu) {
2203 		free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2204 		free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2205 		free_pages(kvm_nvhe_sym(kvm_arm_hyp_host_fp_state)[cpu],
2206 					pkvm_host_fp_state_order());
2207 	}
2208 }
2209 
do_pkvm_init(u32 hyp_va_bits)2210 static int __init do_pkvm_init(u32 hyp_va_bits)
2211 {
2212 	void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2213 	int ret;
2214 
2215 	preempt_disable();
2216 	cpu_hyp_init_context();
2217 	ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2218 				num_possible_cpus(), kern_hyp_va(per_cpu_base),
2219 				hyp_va_bits);
2220 	cpu_hyp_init_features();
2221 
2222 	/*
2223 	 * The stub hypercalls are now disabled, so set our local flag to
2224 	 * prevent a later re-init attempt in kvm_arch_hardware_enable().
2225 	 */
2226 	__this_cpu_write(kvm_hyp_initialized, 1);
2227 	preempt_enable();
2228 
2229 	return ret;
2230 }
2231 
get_hyp_id_aa64pfr0_el1(void)2232 static u64 get_hyp_id_aa64pfr0_el1(void)
2233 {
2234 	/*
2235 	 * Track whether the system isn't affected by spectre/meltdown in the
2236 	 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2237 	 * Although this is per-CPU, we make it global for simplicity, e.g., not
2238 	 * to have to worry about vcpu migration.
2239 	 *
2240 	 * Unlike for non-protected VMs, userspace cannot override this for
2241 	 * protected VMs.
2242 	 */
2243 	u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2244 
2245 	val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
2246 		 ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
2247 
2248 	val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2),
2249 			  arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2250 	val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3),
2251 			  arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2252 
2253 	return val;
2254 }
2255 
kvm_hyp_init_symbols(void)2256 static void kvm_hyp_init_symbols(void)
2257 {
2258 	kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2259 	kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2260 	kvm_nvhe_sym(id_aa64zfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ZFR0_EL1);
2261 	kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2262 	kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2263 	kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2264 	kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2265 	kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2266 	kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2267 	kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2268 	kvm_nvhe_sym(__icache_flags) = __icache_flags;
2269 	kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2270 	kvm_nvhe_sym(smccc_trng_available) = smccc_trng_available;
2271 	kvm_nvhe_sym(kvm_sve_max_vl) = kvm_sve_max_vl;
2272 	kvm_nvhe_sym(kvm_host_sve_max_vl) = kvm_host_sve_max_vl;
2273 }
2274 
kvm_hyp_shrinker_count(struct shrinker * shrinker,struct shrink_control * sc)2275 static unsigned long kvm_hyp_shrinker_count(struct shrinker *shrinker,
2276 					    struct shrink_control *sc)
2277 {
2278 	unsigned long reclaimable = kvm_call_hyp_nvhe(__pkvm_hyp_alloc_mgt_reclaimable);
2279 
2280 	return reclaimable ? reclaimable : SHRINK_EMPTY;
2281 }
2282 
kvm_hyp_shrinker_scan(struct shrinker * shrinker,struct shrink_control * sc)2283 static unsigned long kvm_hyp_shrinker_scan(struct shrinker *shrinker,
2284 					   struct shrink_control *sc)
2285 {
2286 	return __pkvm_reclaim_hyp_alloc_mgt(sc->nr_to_scan);
2287 }
2288 
2289 static struct shrinker kvm_hyp_shrinker = {
2290 	.count_objects	= kvm_hyp_shrinker_count,
2291 	.scan_objects	= kvm_hyp_shrinker_scan,
2292 	.seeks		= DEFAULT_SEEKS,
2293 };
2294 
kvm_hyp_init_protection(u32 hyp_va_bits)2295 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2296 {
2297 	void *addr = phys_to_virt(hyp_mem_base);
2298 	int ret;
2299 
2300 	ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2301 	if (ret)
2302 		return ret;
2303 
2304 	ret = do_pkvm_init(hyp_va_bits);
2305 	if (ret)
2306 		return ret;
2307 
2308 	free_hyp_pgds();
2309 
2310 	if (register_shrinker(&kvm_hyp_shrinker, "pkvm"))
2311 		pr_warn("Failed to register pKVM shrinker");
2312 
2313 	return 0;
2314 }
2315 
init_pkvm_host_fp_state(void)2316 static int init_pkvm_host_fp_state(void)
2317 {
2318 	int cpu;
2319 
2320 	if (!is_protected_kvm_enabled())
2321 		return 0;
2322 
2323 	/* Allocate pages for protected-mode host-fp state. */
2324 	for_each_possible_cpu(cpu) {
2325 		struct page *page;
2326 		unsigned long addr;
2327 
2328 		page = alloc_pages(GFP_KERNEL, pkvm_host_fp_state_order());
2329 		if (!page)
2330 			return -ENOMEM;
2331 
2332 		addr = (unsigned long)page_address(page);
2333 		kvm_nvhe_sym(kvm_arm_hyp_host_fp_state)[cpu] = addr;
2334 	}
2335 
2336 	/*
2337 	 * Don't map the pages in hyp since these are only used in protected
2338 	 * mode, which will (re)create its own mapping when initialized.
2339 	 */
2340 
2341 	return 0;
2342 }
2343 
2344 /*
2345  * Finalizes the initialization of hyp mode, once everything else is initialized
2346  * and the initialziation process cannot fail.
2347  */
finalize_init_hyp_mode(void)2348 static void finalize_init_hyp_mode(void)
2349 {
2350 	int cpu;
2351 
2352 	for_each_possible_cpu(cpu) {
2353 		kvm_nvhe_sym(kvm_arm_hyp_host_fp_state)[cpu] =
2354 			kern_hyp_va(kvm_nvhe_sym(kvm_arm_hyp_host_fp_state)[cpu]);
2355 	}
2356 }
2357 
pkvm_hyp_init_ptrauth(void)2358 static void pkvm_hyp_init_ptrauth(void)
2359 {
2360 	struct kvm_cpu_context *hyp_ctxt;
2361 	int cpu;
2362 
2363 	for_each_possible_cpu(cpu) {
2364 		hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2365 		hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2366 		hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2367 		hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2368 		hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2369 		hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2370 		hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2371 		hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2372 		hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2373 		hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2374 		hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2375 	}
2376 }
2377 
2378 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2379 static int __init init_hyp_mode(void)
2380 {
2381 	u32 hyp_va_bits;
2382 	int cpu;
2383 	int err = -ENOMEM;
2384 
2385 	/*
2386 	 * The protected Hyp-mode cannot be initialized if the memory pool
2387 	 * allocation has failed.
2388 	 */
2389 	if (is_protected_kvm_enabled() && !hyp_mem_base)
2390 		goto out_err;
2391 
2392 	/*
2393 	 * Allocate Hyp PGD and setup Hyp identity mapping
2394 	 */
2395 	err = kvm_mmu_init(&hyp_va_bits);
2396 	if (err)
2397 		goto out_err;
2398 
2399 	/*
2400 	 * Allocate stack pages for Hypervisor-mode
2401 	 */
2402 	for_each_possible_cpu(cpu) {
2403 		unsigned long stack_base;
2404 
2405 		stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2406 		if (!stack_base) {
2407 			err = -ENOMEM;
2408 			goto out_err;
2409 		}
2410 
2411 		per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2412 	}
2413 
2414 	/*
2415 	 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2416 	 */
2417 	for_each_possible_cpu(cpu) {
2418 		struct page *page;
2419 		void *page_addr;
2420 
2421 		page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2422 		if (!page) {
2423 			err = -ENOMEM;
2424 			goto out_err;
2425 		}
2426 
2427 		page_addr = page_address(page);
2428 		memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2429 		kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2430 	}
2431 
2432 	/*
2433 	 * Map the Hyp-code called directly from the host
2434 	 */
2435 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2436 				  kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2437 	if (err) {
2438 		kvm_err("Cannot map world-switch code\n");
2439 		goto out_err;
2440 	}
2441 
2442 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2443 				  kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2444 	if (err) {
2445 		kvm_err("Cannot map .hyp.data section\n");
2446 		goto out_err;
2447 	}
2448 
2449 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2450 				  kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2451 	if (err) {
2452 		kvm_err("Cannot map .hyp.rodata section\n");
2453 		goto out_err;
2454 	}
2455 
2456 	err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2457 				  kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2458 	if (err) {
2459 		kvm_err("Cannot map rodata section\n");
2460 		goto out_err;
2461 	}
2462 
2463 	/*
2464 	 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2465 	 * section thanks to an assertion in the linker script. Map it RW and
2466 	 * the rest of .bss RO.
2467 	 */
2468 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2469 				  kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2470 	if (err) {
2471 		kvm_err("Cannot map hyp bss section: %d\n", err);
2472 		goto out_err;
2473 	}
2474 
2475 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2476 				  kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2477 	if (err) {
2478 		kvm_err("Cannot map bss section\n");
2479 		goto out_err;
2480 	}
2481 
2482 	/*
2483 	 * Map the Hyp stack pages
2484 	 */
2485 	for_each_possible_cpu(cpu) {
2486 		struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2487 		char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2488 
2489 		err = create_hyp_stack(__pa(stack_base), &params->stack_hyp_va);
2490 		if (err) {
2491 			kvm_err("Cannot map hyp stack\n");
2492 			goto out_err;
2493 		}
2494 
2495 		/*
2496 		 * Save the stack PA in nvhe_init_params. This will be needed
2497 		 * to recreate the stack mapping in protected nVHE mode.
2498 		 * __hyp_pa() won't do the right thing there, since the stack
2499 		 * has been mapped in the flexible private VA space.
2500 		 */
2501 		params->stack_pa = __pa(stack_base);
2502 	}
2503 
2504 	for_each_possible_cpu(cpu) {
2505 		char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2506 		char *percpu_end = percpu_begin + nvhe_percpu_size();
2507 
2508 		/* Map Hyp percpu pages */
2509 		err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2510 		if (err) {
2511 			kvm_err("Cannot map hyp percpu region\n");
2512 			goto out_err;
2513 		}
2514 
2515 		/* Prepare the CPU initialization parameters */
2516 		cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2517 	}
2518 
2519 	err = init_pkvm_host_fp_state();
2520 	if (err)
2521 		goto out_err;
2522 
2523 	kvm_hyp_init_symbols();
2524 
2525 	hyp_trace_init_events();
2526 
2527 	if (is_protected_kvm_enabled()) {
2528 		if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2529 		    cpus_have_const_cap(ARM64_HAS_ADDRESS_AUTH))
2530 			pkvm_hyp_init_ptrauth();
2531 
2532 		init_cpu_logical_map();
2533 
2534 		if (!init_psci_relay()) {
2535 			err = -ENODEV;
2536 			goto out_err;
2537 		}
2538 
2539 		err = kvm_hyp_init_protection(hyp_va_bits);
2540 		if (err) {
2541 			kvm_err("Failed to init hyp memory protection\n");
2542 			goto out_err;
2543 		}
2544 	}
2545 
2546 	return 0;
2547 
2548 out_err:
2549 	teardown_hyp_mode();
2550 	kvm_err("error initializing Hyp mode: %d\n", err);
2551 	return err;
2552 }
2553 
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2554 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2555 {
2556 	struct kvm_vcpu *vcpu;
2557 	unsigned long i;
2558 
2559 	mpidr &= MPIDR_HWID_BITMASK;
2560 	kvm_for_each_vcpu(i, vcpu, kvm) {
2561 		if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2562 			return vcpu;
2563 	}
2564 	return NULL;
2565 }
2566 
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2567 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2568 {
2569 	return irqchip_in_kernel(kvm);
2570 }
2571 
kvm_arch_has_irq_bypass(void)2572 bool kvm_arch_has_irq_bypass(void)
2573 {
2574 	return true;
2575 }
2576 
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2577 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2578 				      struct irq_bypass_producer *prod)
2579 {
2580 	struct kvm_kernel_irqfd *irqfd =
2581 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2582 
2583 	return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2584 					  &irqfd->irq_entry);
2585 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2586 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2587 				      struct irq_bypass_producer *prod)
2588 {
2589 	struct kvm_kernel_irqfd *irqfd =
2590 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2591 
2592 	kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2593 				     &irqfd->irq_entry);
2594 }
2595 
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2596 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2597 {
2598 	struct kvm_kernel_irqfd *irqfd =
2599 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2600 
2601 	kvm_arm_halt_guest(irqfd->kvm);
2602 }
2603 
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2604 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2605 {
2606 	struct kvm_kernel_irqfd *irqfd =
2607 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2608 
2609 	kvm_arm_resume_guest(irqfd->kvm);
2610 }
2611 
2612 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2613 static __init int kvm_arm_init(void)
2614 {
2615 	int err;
2616 	bool in_hyp_mode;
2617 
2618 	if (!is_hyp_mode_available()) {
2619 		kvm_info("HYP mode not available\n");
2620 		return -ENODEV;
2621 	}
2622 
2623 	if (kvm_get_mode() == KVM_MODE_NONE) {
2624 		kvm_info("KVM disabled from command line\n");
2625 		return -ENODEV;
2626 	}
2627 
2628 	err = kvm_sys_reg_table_init();
2629 	if (err) {
2630 		kvm_info("Error initializing system register tables");
2631 		return err;
2632 	}
2633 
2634 	in_hyp_mode = is_kernel_in_hyp_mode();
2635 
2636 	if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2637 	    cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2638 		kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2639 			 "Only trusted guests should be used on this system.\n");
2640 
2641 	err = kvm_set_ipa_limit();
2642 	if (err)
2643 		return err;
2644 
2645 	err = kvm_arm_init_sve();
2646 	if (err)
2647 		return err;
2648 
2649 	err = kvm_arm_vmid_alloc_init();
2650 	if (err) {
2651 		kvm_err("Failed to initialize VMID allocator.\n");
2652 		return err;
2653 	}
2654 
2655 	if (!in_hyp_mode) {
2656 		err = init_hyp_mode();
2657 		if (err)
2658 			goto out_err;
2659 	}
2660 
2661 	err = kvm_init_vector_slots();
2662 	if (err) {
2663 		kvm_err("Cannot initialise vector slots\n");
2664 		goto out_hyp;
2665 	}
2666 
2667 	err = init_subsystems();
2668 	if (err)
2669 		goto out_hyp;
2670 
2671 	if (is_protected_kvm_enabled()) {
2672 		kvm_info("Protected nVHE mode initialized successfully\n");
2673 	} else if (in_hyp_mode) {
2674 		kvm_info("VHE mode initialized successfully\n");
2675 	} else {
2676 		kvm_info("Hyp mode initialized successfully\n");
2677 	}
2678 
2679 	/*
2680 	 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2681 	 * hypervisor protection is finalized.
2682 	 */
2683 	err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2684 	if (err)
2685 		goto out_subs;
2686 
2687 	/*
2688 	 * This should be called after initialization is done and failure isn't
2689 	 * possible anymore.
2690 	 */
2691 	if (!in_hyp_mode)
2692 		finalize_init_hyp_mode();
2693 
2694 	kvm_arm_initialised = true;
2695 
2696 	return 0;
2697 
2698 out_subs:
2699 	teardown_subsystems();
2700 out_hyp:
2701 	if (!in_hyp_mode)
2702 		teardown_hyp_mode();
2703 out_err:
2704 	kvm_arm_vmid_alloc_free();
2705 	return err;
2706 }
2707 
early_kvm_mode_cfg(char * arg)2708 static int __init early_kvm_mode_cfg(char *arg)
2709 {
2710 	if (!arg)
2711 		return -EINVAL;
2712 
2713 	if (strcmp(arg, "none") == 0) {
2714 		kvm_mode = KVM_MODE_NONE;
2715 		return 0;
2716 	}
2717 
2718 	if (!is_hyp_mode_available()) {
2719 		pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2720 		return 0;
2721 	}
2722 
2723 	if (strcmp(arg, "protected") == 0) {
2724 		if (!is_kernel_in_hyp_mode())
2725 			kvm_mode = KVM_MODE_PROTECTED;
2726 		else
2727 			pr_warn_once("Protected KVM not available with VHE\n");
2728 
2729 		return 0;
2730 	}
2731 
2732 	if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2733 		kvm_mode = KVM_MODE_DEFAULT;
2734 		return 0;
2735 	}
2736 
2737 	if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2738 		kvm_mode = KVM_MODE_NV;
2739 		return 0;
2740 	}
2741 
2742 	return -EINVAL;
2743 }
2744 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2745 
kvm_get_mode(void)2746 enum kvm_mode kvm_get_mode(void)
2747 {
2748 	return kvm_mode;
2749 }
2750 
2751 module_init(kvm_arm_init);
2752