1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
4  * Author: Christoffer Dall <[email protected]>
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/psci.h>
24 #include <trace/events/kvm.h>
25 
26 #define CREATE_TRACE_POINTS
27 #include "trace_arm.h"
28 
29 #include <linux/uaccess.h>
30 #include <asm/ptrace.h>
31 #include <asm/mman.h>
32 #include <asm/tlbflush.h>
33 #include <asm/cacheflush.h>
34 #include <asm/cpufeature.h>
35 #include <asm/virt.h>
36 #include <asm/kvm_arm.h>
37 #include <asm/kvm_asm.h>
38 #include <asm/kvm_emulate.h>
39 #include <asm/kvm_mmu.h>
40 #include <asm/kvm_nested.h>
41 #include <asm/kvm_pkvm.h>
42 #include <asm/kvm_ptrauth.h>
43 #include <asm/sections.h>
44 
45 #include <kvm/arm_hypercalls.h>
46 #include <kvm/arm_pmu.h>
47 #include <kvm/arm_psci.h>
48 
49 #include "sys_regs.h"
50 
51 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
52 
53 enum kvm_wfx_trap_policy {
54 	KVM_WFX_NOTRAP_SINGLE_TASK, /* Default option */
55 	KVM_WFX_NOTRAP,
56 	KVM_WFX_TRAP,
57 };
58 
59 static enum kvm_wfx_trap_policy kvm_wfi_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
60 static enum kvm_wfx_trap_policy kvm_wfe_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
61 
62 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
63 
64 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_base);
65 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
66 
67 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
68 
69 static bool vgic_present, kvm_arm_initialised;
70 
71 static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized);
72 
is_kvm_arm_initialised(void)73 bool is_kvm_arm_initialised(void)
74 {
75 	return kvm_arm_initialised;
76 }
77 
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)78 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
79 {
80 	return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
81 }
82 
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)83 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
84 			    struct kvm_enable_cap *cap)
85 {
86 	int r = -EINVAL;
87 
88 	if (cap->flags)
89 		return -EINVAL;
90 
91 	if (kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(cap->cap))
92 		return -EINVAL;
93 
94 	switch (cap->cap) {
95 	case KVM_CAP_ARM_NISV_TO_USER:
96 		r = 0;
97 		set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
98 			&kvm->arch.flags);
99 		break;
100 	case KVM_CAP_ARM_MTE:
101 		mutex_lock(&kvm->lock);
102 		if (system_supports_mte() && !kvm->created_vcpus) {
103 			r = 0;
104 			set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
105 		}
106 		mutex_unlock(&kvm->lock);
107 		break;
108 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
109 		r = 0;
110 		set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
111 		break;
112 	case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
113 		mutex_lock(&kvm->slots_lock);
114 		/*
115 		 * To keep things simple, allow changing the chunk
116 		 * size only when no memory slots have been created.
117 		 */
118 		if (kvm_are_all_memslots_empty(kvm)) {
119 			u64 new_cap = cap->args[0];
120 
121 			if (!new_cap || kvm_is_block_size_supported(new_cap)) {
122 				r = 0;
123 				kvm->arch.mmu.split_page_chunk_size = new_cap;
124 			}
125 		}
126 		mutex_unlock(&kvm->slots_lock);
127 		break;
128 	default:
129 		break;
130 	}
131 
132 	return r;
133 }
134 
kvm_arm_default_max_vcpus(void)135 static int kvm_arm_default_max_vcpus(void)
136 {
137 	return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
138 }
139 
140 /**
141  * kvm_arch_init_vm - initializes a VM data structure
142  * @kvm:	pointer to the KVM struct
143  * @type:	kvm device type
144  */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)145 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
146 {
147 	int ret;
148 
149 	mutex_init(&kvm->arch.config_lock);
150 
151 #ifdef CONFIG_LOCKDEP
152 	/* Clue in lockdep that the config_lock must be taken inside kvm->lock */
153 	mutex_lock(&kvm->lock);
154 	mutex_lock(&kvm->arch.config_lock);
155 	mutex_unlock(&kvm->arch.config_lock);
156 	mutex_unlock(&kvm->lock);
157 #endif
158 
159 	kvm_init_nested(kvm);
160 
161 	ret = kvm_share_hyp(kvm, kvm + 1);
162 	if (ret)
163 		return ret;
164 
165 	ret = pkvm_init_host_vm(kvm);
166 	if (ret)
167 		goto err_unshare_kvm;
168 
169 	if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) {
170 		ret = -ENOMEM;
171 		goto err_unshare_kvm;
172 	}
173 	cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
174 
175 	ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
176 	if (ret)
177 		goto err_free_cpumask;
178 
179 	kvm_vgic_early_init(kvm);
180 
181 	kvm_timer_init_vm(kvm);
182 
183 	/* The maximum number of VCPUs is limited by the host's GIC model */
184 	kvm->max_vcpus = kvm_arm_default_max_vcpus();
185 
186 	kvm_arm_init_hypercalls(kvm);
187 
188 	bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
189 
190 	return 0;
191 
192 err_free_cpumask:
193 	free_cpumask_var(kvm->arch.supported_cpus);
194 err_unshare_kvm:
195 	kvm_unshare_hyp(kvm, kvm + 1);
196 	return ret;
197 }
198 
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)199 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
200 {
201 	return VM_FAULT_SIGBUS;
202 }
203 
kvm_arch_create_vm_debugfs(struct kvm * kvm)204 void kvm_arch_create_vm_debugfs(struct kvm *kvm)
205 {
206 	kvm_sys_regs_create_debugfs(kvm);
207 	kvm_s2_ptdump_create_debugfs(kvm);
208 }
209 
kvm_destroy_mpidr_data(struct kvm * kvm)210 static void kvm_destroy_mpidr_data(struct kvm *kvm)
211 {
212 	struct kvm_mpidr_data *data;
213 
214 	mutex_lock(&kvm->arch.config_lock);
215 
216 	data = rcu_dereference_protected(kvm->arch.mpidr_data,
217 					 lockdep_is_held(&kvm->arch.config_lock));
218 	if (data) {
219 		rcu_assign_pointer(kvm->arch.mpidr_data, NULL);
220 		synchronize_rcu();
221 		kfree(data);
222 	}
223 
224 	mutex_unlock(&kvm->arch.config_lock);
225 }
226 
227 /**
228  * kvm_arch_destroy_vm - destroy the VM data structure
229  * @kvm:	pointer to the KVM struct
230  */
kvm_arch_destroy_vm(struct kvm * kvm)231 void kvm_arch_destroy_vm(struct kvm *kvm)
232 {
233 	bitmap_free(kvm->arch.pmu_filter);
234 	free_cpumask_var(kvm->arch.supported_cpus);
235 
236 	kvm_vgic_destroy(kvm);
237 
238 	if (is_protected_kvm_enabled())
239 		pkvm_destroy_hyp_vm(kvm);
240 
241 	kvm_destroy_mpidr_data(kvm);
242 
243 	kfree(kvm->arch.sysreg_masks);
244 	kvm_destroy_vcpus(kvm);
245 
246 	kvm_unshare_hyp(kvm, kvm + 1);
247 
248 	kvm_arm_teardown_hypercalls(kvm);
249 }
250 
kvm_has_full_ptr_auth(void)251 static bool kvm_has_full_ptr_auth(void)
252 {
253 	bool apa, gpa, api, gpi, apa3, gpa3;
254 	u64 isar1, isar2, val;
255 
256 	/*
257 	 * Check that:
258 	 *
259 	 * - both Address and Generic auth are implemented for a given
260          *   algorithm (Q5, IMPDEF or Q3)
261 	 * - only a single algorithm is implemented.
262 	 */
263 	if (!system_has_full_ptr_auth())
264 		return false;
265 
266 	isar1 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
267 	isar2 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
268 
269 	apa = !!FIELD_GET(ID_AA64ISAR1_EL1_APA_MASK, isar1);
270 	val = FIELD_GET(ID_AA64ISAR1_EL1_GPA_MASK, isar1);
271 	gpa = (val == ID_AA64ISAR1_EL1_GPA_IMP);
272 
273 	api = !!FIELD_GET(ID_AA64ISAR1_EL1_API_MASK, isar1);
274 	val = FIELD_GET(ID_AA64ISAR1_EL1_GPI_MASK, isar1);
275 	gpi = (val == ID_AA64ISAR1_EL1_GPI_IMP);
276 
277 	apa3 = !!FIELD_GET(ID_AA64ISAR2_EL1_APA3_MASK, isar2);
278 	val  = FIELD_GET(ID_AA64ISAR2_EL1_GPA3_MASK, isar2);
279 	gpa3 = (val == ID_AA64ISAR2_EL1_GPA3_IMP);
280 
281 	return (apa == gpa && api == gpi && apa3 == gpa3 &&
282 		(apa + api + apa3) == 1);
283 }
284 
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)285 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
286 {
287 	int r;
288 
289 	if (kvm && kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(ext))
290 		return 0;
291 
292 	switch (ext) {
293 	case KVM_CAP_IRQCHIP:
294 		r = vgic_present;
295 		break;
296 	case KVM_CAP_IOEVENTFD:
297 	case KVM_CAP_USER_MEMORY:
298 	case KVM_CAP_SYNC_MMU:
299 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
300 	case KVM_CAP_ONE_REG:
301 	case KVM_CAP_ARM_PSCI:
302 	case KVM_CAP_ARM_PSCI_0_2:
303 	case KVM_CAP_READONLY_MEM:
304 	case KVM_CAP_MP_STATE:
305 	case KVM_CAP_IMMEDIATE_EXIT:
306 	case KVM_CAP_VCPU_EVENTS:
307 	case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
308 	case KVM_CAP_ARM_NISV_TO_USER:
309 	case KVM_CAP_ARM_INJECT_EXT_DABT:
310 	case KVM_CAP_SET_GUEST_DEBUG:
311 	case KVM_CAP_VCPU_ATTRIBUTES:
312 	case KVM_CAP_PTP_KVM:
313 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
314 	case KVM_CAP_IRQFD_RESAMPLE:
315 	case KVM_CAP_COUNTER_OFFSET:
316 		r = 1;
317 		break;
318 	case KVM_CAP_SET_GUEST_DEBUG2:
319 		return KVM_GUESTDBG_VALID_MASK;
320 	case KVM_CAP_ARM_SET_DEVICE_ADDR:
321 		r = 1;
322 		break;
323 	case KVM_CAP_NR_VCPUS:
324 		/*
325 		 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
326 		 * architectures, as it does not always bound it to
327 		 * KVM_CAP_MAX_VCPUS. It should not matter much because
328 		 * this is just an advisory value.
329 		 */
330 		r = min_t(unsigned int, num_online_cpus(),
331 			  kvm_arm_default_max_vcpus());
332 		break;
333 	case KVM_CAP_MAX_VCPUS:
334 	case KVM_CAP_MAX_VCPU_ID:
335 		if (kvm)
336 			r = kvm->max_vcpus;
337 		else
338 			r = kvm_arm_default_max_vcpus();
339 		break;
340 	case KVM_CAP_MSI_DEVID:
341 		if (!kvm)
342 			r = -EINVAL;
343 		else
344 			r = kvm->arch.vgic.msis_require_devid;
345 		break;
346 	case KVM_CAP_ARM_USER_IRQ:
347 		/*
348 		 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
349 		 * (bump this number if adding more devices)
350 		 */
351 		r = 1;
352 		break;
353 	case KVM_CAP_ARM_MTE:
354 		r = system_supports_mte();
355 		break;
356 	case KVM_CAP_STEAL_TIME:
357 		r = kvm_arm_pvtime_supported();
358 		break;
359 	case KVM_CAP_ARM_EL1_32BIT:
360 		r = cpus_have_final_cap(ARM64_HAS_32BIT_EL1);
361 		break;
362 	case KVM_CAP_GUEST_DEBUG_HW_BPS:
363 		r = get_num_brps();
364 		break;
365 	case KVM_CAP_GUEST_DEBUG_HW_WPS:
366 		r = get_num_wrps();
367 		break;
368 	case KVM_CAP_ARM_PMU_V3:
369 		r = kvm_arm_support_pmu_v3();
370 		break;
371 	case KVM_CAP_ARM_INJECT_SERROR_ESR:
372 		r = cpus_have_final_cap(ARM64_HAS_RAS_EXTN);
373 		break;
374 	case KVM_CAP_ARM_VM_IPA_SIZE:
375 		r = get_kvm_ipa_limit();
376 		break;
377 	case KVM_CAP_ARM_SVE:
378 		r = system_supports_sve();
379 		break;
380 	case KVM_CAP_ARM_PTRAUTH_ADDRESS:
381 	case KVM_CAP_ARM_PTRAUTH_GENERIC:
382 		r = kvm_has_full_ptr_auth();
383 		break;
384 	case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
385 		if (kvm)
386 			r = kvm->arch.mmu.split_page_chunk_size;
387 		else
388 			r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT;
389 		break;
390 	case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES:
391 		r = kvm_supported_block_sizes();
392 		break;
393 	case KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES:
394 		r = BIT(0);
395 		break;
396 	default:
397 		r = 0;
398 	}
399 
400 	return r;
401 }
402 
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)403 long kvm_arch_dev_ioctl(struct file *filp,
404 			unsigned int ioctl, unsigned long arg)
405 {
406 	return -EINVAL;
407 }
408 
kvm_arch_alloc_vm(void)409 struct kvm *kvm_arch_alloc_vm(void)
410 {
411 	size_t sz = sizeof(struct kvm);
412 
413 	if (!has_vhe())
414 		return kzalloc(sz, GFP_KERNEL_ACCOUNT);
415 
416 	return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
417 }
418 
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)419 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
420 {
421 	if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
422 		return -EBUSY;
423 
424 	if (id >= kvm->max_vcpus)
425 		return -EINVAL;
426 
427 	return 0;
428 }
429 
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)430 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
431 {
432 	int err;
433 
434 	spin_lock_init(&vcpu->arch.mp_state_lock);
435 
436 #ifdef CONFIG_LOCKDEP
437 	/* Inform lockdep that the config_lock is acquired after vcpu->mutex */
438 	mutex_lock(&vcpu->mutex);
439 	mutex_lock(&vcpu->kvm->arch.config_lock);
440 	mutex_unlock(&vcpu->kvm->arch.config_lock);
441 	mutex_unlock(&vcpu->mutex);
442 #endif
443 
444 	/* Force users to call KVM_ARM_VCPU_INIT */
445 	vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
446 
447 	vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
448 
449 	/* Set up the timer */
450 	kvm_timer_vcpu_init(vcpu);
451 
452 	kvm_pmu_vcpu_init(vcpu);
453 
454 	kvm_arm_pvtime_vcpu_init(&vcpu->arch);
455 
456 	vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
457 
458 	/*
459 	 * This vCPU may have been created after mpidr_data was initialized.
460 	 * Throw out the pre-computed mappings if that is the case which forces
461 	 * KVM to fall back to iteratively searching the vCPUs.
462 	 */
463 	kvm_destroy_mpidr_data(vcpu->kvm);
464 
465 	err = kvm_vgic_vcpu_init(vcpu);
466 	if (err)
467 		return err;
468 
469 	err = kvm_share_hyp(vcpu, vcpu + 1);
470 	if (err)
471 		kvm_vgic_vcpu_destroy(vcpu);
472 
473 	return err;
474 }
475 
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)476 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
477 {
478 }
479 
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)480 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
481 {
482 	if (!is_protected_kvm_enabled())
483 		kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
484 	else
485 		free_hyp_memcache(&vcpu->arch.pkvm_memcache);
486 	kvm_timer_vcpu_terminate(vcpu);
487 	kvm_pmu_vcpu_destroy(vcpu);
488 	kvm_vgic_vcpu_destroy(vcpu);
489 	kvm_arm_vcpu_destroy(vcpu);
490 }
491 
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)492 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
493 {
494 
495 }
496 
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)497 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
498 {
499 
500 }
501 
vcpu_set_pauth_traps(struct kvm_vcpu * vcpu)502 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
503 {
504 	if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
505 		/*
506 		 * Either we're running an L2 guest, and the API/APK bits come
507 		 * from L1's HCR_EL2, or API/APK are both set.
508 		 */
509 		if (unlikely(vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu))) {
510 			u64 val;
511 
512 			val = __vcpu_sys_reg(vcpu, HCR_EL2);
513 			val &= (HCR_API | HCR_APK);
514 			vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
515 			vcpu->arch.hcr_el2 |= val;
516 		} else {
517 			vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
518 		}
519 
520 		/*
521 		 * Save the host keys if there is any chance for the guest
522 		 * to use pauth, as the entry code will reload the guest
523 		 * keys in that case.
524 		 */
525 		if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
526 			struct kvm_cpu_context *ctxt;
527 
528 			ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
529 			ptrauth_save_keys(ctxt);
530 		}
531 	}
532 }
533 
kvm_vcpu_should_clear_twi(struct kvm_vcpu * vcpu)534 static bool kvm_vcpu_should_clear_twi(struct kvm_vcpu *vcpu)
535 {
536 	if (unlikely(kvm_wfi_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
537 		return kvm_wfi_trap_policy == KVM_WFX_NOTRAP;
538 
539 	return single_task_running() &&
540 	       (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
541 		vcpu->kvm->arch.vgic.nassgireq);
542 }
543 
kvm_vcpu_should_clear_twe(struct kvm_vcpu * vcpu)544 static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu)
545 {
546 	if (unlikely(kvm_wfe_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
547 		return kvm_wfe_trap_policy == KVM_WFX_NOTRAP;
548 
549 	return single_task_running();
550 }
551 
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)552 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
553 {
554 	struct kvm_s2_mmu *mmu;
555 	int *last_ran;
556 
557 	if (is_protected_kvm_enabled())
558 		goto nommu;
559 
560 	if (vcpu_has_nv(vcpu))
561 		kvm_vcpu_load_hw_mmu(vcpu);
562 
563 	mmu = vcpu->arch.hw_mmu;
564 	last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
565 
566 	/*
567 	 * Ensure a VMID is allocated for the MMU before programming VTTBR_EL2,
568 	 * which happens eagerly in VHE.
569 	 *
570 	 * Also, the VMID allocator only preserves VMIDs that are active at the
571 	 * time of rollover, so KVM might need to grab a new VMID for the MMU if
572 	 * this is called from kvm_sched_in().
573 	 */
574 	kvm_arm_vmid_update(&mmu->vmid);
575 
576 	/*
577 	 * We guarantee that both TLBs and I-cache are private to each
578 	 * vcpu. If detecting that a vcpu from the same VM has
579 	 * previously run on the same physical CPU, call into the
580 	 * hypervisor code to nuke the relevant contexts.
581 	 *
582 	 * We might get preempted before the vCPU actually runs, but
583 	 * over-invalidation doesn't affect correctness.
584 	 */
585 	if (*last_ran != vcpu->vcpu_idx) {
586 		kvm_call_hyp(__kvm_flush_cpu_context, mmu);
587 		*last_ran = vcpu->vcpu_idx;
588 	}
589 
590 nommu:
591 	vcpu->cpu = cpu;
592 
593 	kvm_vgic_load(vcpu);
594 	kvm_timer_vcpu_load(vcpu);
595 	kvm_vcpu_load_debug(vcpu);
596 	if (has_vhe())
597 		kvm_vcpu_load_vhe(vcpu);
598 	kvm_arch_vcpu_load_fp(vcpu);
599 	kvm_vcpu_pmu_restore_guest(vcpu);
600 	if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
601 		kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
602 
603 	if (kvm_vcpu_should_clear_twe(vcpu))
604 		vcpu->arch.hcr_el2 &= ~HCR_TWE;
605 	else
606 		vcpu->arch.hcr_el2 |= HCR_TWE;
607 
608 	if (kvm_vcpu_should_clear_twi(vcpu))
609 		vcpu->arch.hcr_el2 &= ~HCR_TWI;
610 	else
611 		vcpu->arch.hcr_el2 |= HCR_TWI;
612 
613 	vcpu_set_pauth_traps(vcpu);
614 
615 	if (is_protected_kvm_enabled()) {
616 		kvm_call_hyp_nvhe(__pkvm_vcpu_load,
617 				  vcpu->kvm->arch.pkvm.handle,
618 				  vcpu->vcpu_idx, vcpu->arch.hcr_el2);
619 		kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
620 			     &vcpu->arch.vgic_cpu.vgic_v3);
621 	}
622 
623 	if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
624 		vcpu_set_on_unsupported_cpu(vcpu);
625 }
626 
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)627 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
628 {
629 	if (is_protected_kvm_enabled()) {
630 		kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
631 			     &vcpu->arch.vgic_cpu.vgic_v3);
632 		kvm_call_hyp_nvhe(__pkvm_vcpu_put);
633 	}
634 
635 	kvm_vcpu_put_debug(vcpu);
636 	kvm_arch_vcpu_put_fp(vcpu);
637 	if (has_vhe())
638 		kvm_vcpu_put_vhe(vcpu);
639 	kvm_timer_vcpu_put(vcpu);
640 	kvm_vgic_put(vcpu);
641 	kvm_vcpu_pmu_restore_host(vcpu);
642 	if (vcpu_has_nv(vcpu))
643 		kvm_vcpu_put_hw_mmu(vcpu);
644 	kvm_arm_vmid_clear_active();
645 
646 	vcpu_clear_on_unsupported_cpu(vcpu);
647 	vcpu->cpu = -1;
648 }
649 
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)650 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
651 {
652 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
653 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
654 	kvm_vcpu_kick(vcpu);
655 }
656 
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)657 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
658 {
659 	spin_lock(&vcpu->arch.mp_state_lock);
660 	__kvm_arm_vcpu_power_off(vcpu);
661 	spin_unlock(&vcpu->arch.mp_state_lock);
662 }
663 
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)664 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
665 {
666 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
667 }
668 
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)669 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
670 {
671 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
672 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
673 	kvm_vcpu_kick(vcpu);
674 }
675 
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)676 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
677 {
678 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
679 }
680 
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)681 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
682 				    struct kvm_mp_state *mp_state)
683 {
684 	*mp_state = READ_ONCE(vcpu->arch.mp_state);
685 
686 	return 0;
687 }
688 
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)689 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
690 				    struct kvm_mp_state *mp_state)
691 {
692 	int ret = 0;
693 
694 	spin_lock(&vcpu->arch.mp_state_lock);
695 
696 	switch (mp_state->mp_state) {
697 	case KVM_MP_STATE_RUNNABLE:
698 		WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
699 		break;
700 	case KVM_MP_STATE_STOPPED:
701 		__kvm_arm_vcpu_power_off(vcpu);
702 		break;
703 	case KVM_MP_STATE_SUSPENDED:
704 		kvm_arm_vcpu_suspend(vcpu);
705 		break;
706 	default:
707 		ret = -EINVAL;
708 	}
709 
710 	spin_unlock(&vcpu->arch.mp_state_lock);
711 
712 	return ret;
713 }
714 
715 /**
716  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
717  * @v:		The VCPU pointer
718  *
719  * If the guest CPU is not waiting for interrupts or an interrupt line is
720  * asserted, the CPU is by definition runnable.
721  */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)722 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
723 {
724 	bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
725 	return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
726 		&& !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
727 }
728 
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)729 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
730 {
731 	return vcpu_mode_priv(vcpu);
732 }
733 
734 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)735 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
736 {
737 	return *vcpu_pc(vcpu);
738 }
739 #endif
740 
kvm_init_mpidr_data(struct kvm * kvm)741 static void kvm_init_mpidr_data(struct kvm *kvm)
742 {
743 	struct kvm_mpidr_data *data = NULL;
744 	unsigned long c, mask, nr_entries;
745 	u64 aff_set = 0, aff_clr = ~0UL;
746 	struct kvm_vcpu *vcpu;
747 
748 	mutex_lock(&kvm->arch.config_lock);
749 
750 	if (rcu_access_pointer(kvm->arch.mpidr_data) ||
751 	    atomic_read(&kvm->online_vcpus) == 1)
752 		goto out;
753 
754 	kvm_for_each_vcpu(c, vcpu, kvm) {
755 		u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
756 		aff_set |= aff;
757 		aff_clr &= aff;
758 	}
759 
760 	/*
761 	 * A significant bit can be either 0 or 1, and will only appear in
762 	 * aff_set. Use aff_clr to weed out the useless stuff.
763 	 */
764 	mask = aff_set ^ aff_clr;
765 	nr_entries = BIT_ULL(hweight_long(mask));
766 
767 	/*
768 	 * Don't let userspace fool us. If we need more than a single page
769 	 * to describe the compressed MPIDR array, just fall back to the
770 	 * iterative method. Single vcpu VMs do not need this either.
771 	 */
772 	if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE)
773 		data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries),
774 			       GFP_KERNEL_ACCOUNT);
775 
776 	if (!data)
777 		goto out;
778 
779 	data->mpidr_mask = mask;
780 
781 	kvm_for_each_vcpu(c, vcpu, kvm) {
782 		u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
783 		u16 index = kvm_mpidr_index(data, aff);
784 
785 		data->cmpidr_to_idx[index] = c;
786 	}
787 
788 	rcu_assign_pointer(kvm->arch.mpidr_data, data);
789 out:
790 	mutex_unlock(&kvm->arch.config_lock);
791 }
792 
793 /*
794  * Handle both the initialisation that is being done when the vcpu is
795  * run for the first time, as well as the updates that must be
796  * performed each time we get a new thread dealing with this vcpu.
797  */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)798 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
799 {
800 	struct kvm *kvm = vcpu->kvm;
801 	int ret;
802 
803 	if (!kvm_vcpu_initialized(vcpu))
804 		return -ENOEXEC;
805 
806 	if (!kvm_arm_vcpu_is_finalized(vcpu))
807 		return -EPERM;
808 
809 	ret = kvm_arch_vcpu_run_map_fp(vcpu);
810 	if (ret)
811 		return ret;
812 
813 	if (likely(vcpu_has_run_once(vcpu)))
814 		return 0;
815 
816 	kvm_init_mpidr_data(kvm);
817 
818 	if (likely(irqchip_in_kernel(kvm))) {
819 		/*
820 		 * Map the VGIC hardware resources before running a vcpu the
821 		 * first time on this VM.
822 		 */
823 		ret = kvm_vgic_map_resources(kvm);
824 		if (ret)
825 			return ret;
826 	}
827 
828 	ret = kvm_finalize_sys_regs(vcpu);
829 	if (ret)
830 		return ret;
831 
832 	/*
833 	 * This needs to happen after any restriction has been applied
834 	 * to the feature set.
835 	 */
836 	kvm_calculate_traps(vcpu);
837 
838 	ret = kvm_timer_enable(vcpu);
839 	if (ret)
840 		return ret;
841 
842 	ret = kvm_arm_pmu_v3_enable(vcpu);
843 	if (ret)
844 		return ret;
845 
846 	if (is_protected_kvm_enabled()) {
847 		ret = pkvm_create_hyp_vm(kvm);
848 		if (ret)
849 			return ret;
850 	}
851 
852 	mutex_lock(&kvm->arch.config_lock);
853 	set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
854 	mutex_unlock(&kvm->arch.config_lock);
855 
856 	return ret;
857 }
858 
kvm_arch_intc_initialized(struct kvm * kvm)859 bool kvm_arch_intc_initialized(struct kvm *kvm)
860 {
861 	return vgic_initialized(kvm);
862 }
863 
kvm_arm_halt_guest(struct kvm * kvm)864 void kvm_arm_halt_guest(struct kvm *kvm)
865 {
866 	unsigned long i;
867 	struct kvm_vcpu *vcpu;
868 
869 	kvm_for_each_vcpu(i, vcpu, kvm)
870 		vcpu->arch.pause = true;
871 	kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
872 }
873 
kvm_arm_resume_guest(struct kvm * kvm)874 void kvm_arm_resume_guest(struct kvm *kvm)
875 {
876 	unsigned long i;
877 	struct kvm_vcpu *vcpu;
878 
879 	kvm_for_each_vcpu(i, vcpu, kvm) {
880 		vcpu->arch.pause = false;
881 		__kvm_vcpu_wake_up(vcpu);
882 	}
883 }
884 
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)885 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
886 {
887 	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
888 
889 	rcuwait_wait_event(wait,
890 			   (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
891 			   TASK_INTERRUPTIBLE);
892 
893 	if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
894 		/* Awaken to handle a signal, request we sleep again later. */
895 		kvm_make_request(KVM_REQ_SLEEP, vcpu);
896 	}
897 
898 	/*
899 	 * Make sure we will observe a potential reset request if we've
900 	 * observed a change to the power state. Pairs with the smp_wmb() in
901 	 * kvm_psci_vcpu_on().
902 	 */
903 	smp_rmb();
904 }
905 
906 /**
907  * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
908  * @vcpu:	The VCPU pointer
909  *
910  * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
911  * the vCPU is runnable.  The vCPU may or may not be scheduled out, depending
912  * on when a wake event arrives, e.g. there may already be a pending wake event.
913  */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)914 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
915 {
916 	/*
917 	 * Sync back the state of the GIC CPU interface so that we have
918 	 * the latest PMR and group enables. This ensures that
919 	 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
920 	 * we have pending interrupts, e.g. when determining if the
921 	 * vCPU should block.
922 	 *
923 	 * For the same reason, we want to tell GICv4 that we need
924 	 * doorbells to be signalled, should an interrupt become pending.
925 	 */
926 	preempt_disable();
927 	vcpu_set_flag(vcpu, IN_WFI);
928 	kvm_vgic_put(vcpu);
929 	preempt_enable();
930 
931 	kvm_vcpu_halt(vcpu);
932 	vcpu_clear_flag(vcpu, IN_WFIT);
933 
934 	preempt_disable();
935 	vcpu_clear_flag(vcpu, IN_WFI);
936 	kvm_vgic_load(vcpu);
937 	preempt_enable();
938 }
939 
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)940 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
941 {
942 	if (!kvm_arm_vcpu_suspended(vcpu))
943 		return 1;
944 
945 	kvm_vcpu_wfi(vcpu);
946 
947 	/*
948 	 * The suspend state is sticky; we do not leave it until userspace
949 	 * explicitly marks the vCPU as runnable. Request that we suspend again
950 	 * later.
951 	 */
952 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
953 
954 	/*
955 	 * Check to make sure the vCPU is actually runnable. If so, exit to
956 	 * userspace informing it of the wakeup condition.
957 	 */
958 	if (kvm_arch_vcpu_runnable(vcpu)) {
959 		memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
960 		vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
961 		vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
962 		return 0;
963 	}
964 
965 	/*
966 	 * Otherwise, we were unblocked to process a different event, such as a
967 	 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
968 	 * process the event.
969 	 */
970 	return 1;
971 }
972 
973 /**
974  * check_vcpu_requests - check and handle pending vCPU requests
975  * @vcpu:	the VCPU pointer
976  *
977  * Return: 1 if we should enter the guest
978  *	   0 if we should exit to userspace
979  *	   < 0 if we should exit to userspace, where the return value indicates
980  *	   an error
981  */
check_vcpu_requests(struct kvm_vcpu * vcpu)982 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
983 {
984 	if (kvm_request_pending(vcpu)) {
985 		if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu))
986 			return -EIO;
987 
988 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
989 			kvm_vcpu_sleep(vcpu);
990 
991 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
992 			kvm_reset_vcpu(vcpu);
993 
994 		/*
995 		 * Clear IRQ_PENDING requests that were made to guarantee
996 		 * that a VCPU sees new virtual interrupts.
997 		 */
998 		kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
999 
1000 		if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
1001 			kvm_update_stolen_time(vcpu);
1002 
1003 		if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
1004 			/* The distributor enable bits were changed */
1005 			preempt_disable();
1006 			vgic_v4_put(vcpu);
1007 			vgic_v4_load(vcpu);
1008 			preempt_enable();
1009 		}
1010 
1011 		if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
1012 			kvm_vcpu_reload_pmu(vcpu);
1013 
1014 		if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
1015 			kvm_vcpu_pmu_restore_guest(vcpu);
1016 
1017 		if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
1018 			return kvm_vcpu_suspend(vcpu);
1019 
1020 		if (kvm_dirty_ring_check_request(vcpu))
1021 			return 0;
1022 
1023 		check_nested_vcpu_requests(vcpu);
1024 	}
1025 
1026 	return 1;
1027 }
1028 
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)1029 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
1030 {
1031 	if (likely(!vcpu_mode_is_32bit(vcpu)))
1032 		return false;
1033 
1034 	if (vcpu_has_nv(vcpu))
1035 		return true;
1036 
1037 	return !kvm_supports_32bit_el0();
1038 }
1039 
1040 /**
1041  * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
1042  * @vcpu:	The VCPU pointer
1043  * @ret:	Pointer to write optional return code
1044  *
1045  * Returns: true if the VCPU needs to return to a preemptible + interruptible
1046  *	    and skip guest entry.
1047  *
1048  * This function disambiguates between two different types of exits: exits to a
1049  * preemptible + interruptible kernel context and exits to userspace. For an
1050  * exit to userspace, this function will write the return code to ret and return
1051  * true. For an exit to preemptible + interruptible kernel context (i.e. check
1052  * for pending work and re-enter), return true without writing to ret.
1053  */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)1054 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
1055 {
1056 	struct kvm_run *run = vcpu->run;
1057 
1058 	/*
1059 	 * If we're using a userspace irqchip, then check if we need
1060 	 * to tell a userspace irqchip about timer or PMU level
1061 	 * changes and if so, exit to userspace (the actual level
1062 	 * state gets updated in kvm_timer_update_run and
1063 	 * kvm_pmu_update_run below).
1064 	 */
1065 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1066 		if (kvm_timer_should_notify_user(vcpu) ||
1067 		    kvm_pmu_should_notify_user(vcpu)) {
1068 			*ret = -EINTR;
1069 			run->exit_reason = KVM_EXIT_INTR;
1070 			return true;
1071 		}
1072 	}
1073 
1074 	if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
1075 		run->exit_reason = KVM_EXIT_FAIL_ENTRY;
1076 		run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
1077 		run->fail_entry.cpu = smp_processor_id();
1078 		*ret = 0;
1079 		return true;
1080 	}
1081 
1082 	return kvm_request_pending(vcpu) ||
1083 			xfer_to_guest_mode_work_pending();
1084 }
1085 
1086 /*
1087  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
1088  * the vCPU is running.
1089  *
1090  * This must be noinstr as instrumentation may make use of RCU, and this is not
1091  * safe during the EQS.
1092  */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1093 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1094 {
1095 	int ret;
1096 
1097 	guest_state_enter_irqoff();
1098 	ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1099 	guest_state_exit_irqoff();
1100 
1101 	return ret;
1102 }
1103 
1104 /**
1105  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1106  * @vcpu:	The VCPU pointer
1107  *
1108  * This function is called through the VCPU_RUN ioctl called from user space. It
1109  * will execute VM code in a loop until the time slice for the process is used
1110  * or some emulation is needed from user space in which case the function will
1111  * return with return value 0 and with the kvm_run structure filled in with the
1112  * required data for the requested emulation.
1113  */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1114 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1115 {
1116 	struct kvm_run *run = vcpu->run;
1117 	int ret;
1118 
1119 	if (run->exit_reason == KVM_EXIT_MMIO) {
1120 		ret = kvm_handle_mmio_return(vcpu);
1121 		if (ret <= 0)
1122 			return ret;
1123 	}
1124 
1125 	vcpu_load(vcpu);
1126 
1127 	if (!vcpu->wants_to_run) {
1128 		ret = -EINTR;
1129 		goto out;
1130 	}
1131 
1132 	kvm_sigset_activate(vcpu);
1133 
1134 	ret = 1;
1135 	run->exit_reason = KVM_EXIT_UNKNOWN;
1136 	run->flags = 0;
1137 	while (ret > 0) {
1138 		/*
1139 		 * Check conditions before entering the guest
1140 		 */
1141 		ret = xfer_to_guest_mode_handle_work(vcpu);
1142 		if (!ret)
1143 			ret = 1;
1144 
1145 		if (ret > 0)
1146 			ret = check_vcpu_requests(vcpu);
1147 
1148 		/*
1149 		 * Preparing the interrupts to be injected also
1150 		 * involves poking the GIC, which must be done in a
1151 		 * non-preemptible context.
1152 		 */
1153 		preempt_disable();
1154 
1155 		kvm_pmu_flush_hwstate(vcpu);
1156 
1157 		local_irq_disable();
1158 
1159 		kvm_vgic_flush_hwstate(vcpu);
1160 
1161 		kvm_pmu_update_vcpu_events(vcpu);
1162 
1163 		/*
1164 		 * Ensure we set mode to IN_GUEST_MODE after we disable
1165 		 * interrupts and before the final VCPU requests check.
1166 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
1167 		 * Documentation/virt/kvm/vcpu-requests.rst
1168 		 */
1169 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1170 
1171 		if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1172 			vcpu->mode = OUTSIDE_GUEST_MODE;
1173 			isb(); /* Ensure work in x_flush_hwstate is committed */
1174 			kvm_pmu_sync_hwstate(vcpu);
1175 			if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1176 				kvm_timer_sync_user(vcpu);
1177 			kvm_vgic_sync_hwstate(vcpu);
1178 			local_irq_enable();
1179 			preempt_enable();
1180 			continue;
1181 		}
1182 
1183 		kvm_arch_vcpu_ctxflush_fp(vcpu);
1184 
1185 		/**************************************************************
1186 		 * Enter the guest
1187 		 */
1188 		trace_kvm_entry(*vcpu_pc(vcpu));
1189 		guest_timing_enter_irqoff();
1190 
1191 		ret = kvm_arm_vcpu_enter_exit(vcpu);
1192 
1193 		vcpu->mode = OUTSIDE_GUEST_MODE;
1194 		vcpu->stat.exits++;
1195 		/*
1196 		 * Back from guest
1197 		 *************************************************************/
1198 
1199 		/*
1200 		 * We must sync the PMU state before the vgic state so
1201 		 * that the vgic can properly sample the updated state of the
1202 		 * interrupt line.
1203 		 */
1204 		kvm_pmu_sync_hwstate(vcpu);
1205 
1206 		/*
1207 		 * Sync the vgic state before syncing the timer state because
1208 		 * the timer code needs to know if the virtual timer
1209 		 * interrupts are active.
1210 		 */
1211 		kvm_vgic_sync_hwstate(vcpu);
1212 
1213 		/*
1214 		 * Sync the timer hardware state before enabling interrupts as
1215 		 * we don't want vtimer interrupts to race with syncing the
1216 		 * timer virtual interrupt state.
1217 		 */
1218 		if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1219 			kvm_timer_sync_user(vcpu);
1220 
1221 		if (is_hyp_ctxt(vcpu))
1222 			kvm_timer_sync_nested(vcpu);
1223 
1224 		kvm_arch_vcpu_ctxsync_fp(vcpu);
1225 
1226 		/*
1227 		 * We must ensure that any pending interrupts are taken before
1228 		 * we exit guest timing so that timer ticks are accounted as
1229 		 * guest time. Transiently unmask interrupts so that any
1230 		 * pending interrupts are taken.
1231 		 *
1232 		 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1233 		 * context synchronization event) is necessary to ensure that
1234 		 * pending interrupts are taken.
1235 		 */
1236 		if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1237 			local_irq_enable();
1238 			isb();
1239 			local_irq_disable();
1240 		}
1241 
1242 		guest_timing_exit_irqoff();
1243 
1244 		local_irq_enable();
1245 
1246 		trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1247 
1248 		/* Exit types that need handling before we can be preempted */
1249 		handle_exit_early(vcpu, ret);
1250 
1251 		preempt_enable();
1252 
1253 		/*
1254 		 * The ARMv8 architecture doesn't give the hypervisor
1255 		 * a mechanism to prevent a guest from dropping to AArch32 EL0
1256 		 * if implemented by the CPU. If we spot the guest in such
1257 		 * state and that we decided it wasn't supposed to do so (like
1258 		 * with the asymmetric AArch32 case), return to userspace with
1259 		 * a fatal error.
1260 		 */
1261 		if (vcpu_mode_is_bad_32bit(vcpu)) {
1262 			/*
1263 			 * As we have caught the guest red-handed, decide that
1264 			 * it isn't fit for purpose anymore by making the vcpu
1265 			 * invalid. The VMM can try and fix it by issuing  a
1266 			 * KVM_ARM_VCPU_INIT if it really wants to.
1267 			 */
1268 			vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1269 			ret = ARM_EXCEPTION_IL;
1270 		}
1271 
1272 		ret = handle_exit(vcpu, ret);
1273 	}
1274 
1275 	/* Tell userspace about in-kernel device output levels */
1276 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1277 		kvm_timer_update_run(vcpu);
1278 		kvm_pmu_update_run(vcpu);
1279 	}
1280 
1281 	kvm_sigset_deactivate(vcpu);
1282 
1283 out:
1284 	/*
1285 	 * In the unlikely event that we are returning to userspace
1286 	 * with pending exceptions or PC adjustment, commit these
1287 	 * adjustments in order to give userspace a consistent view of
1288 	 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1289 	 * being preempt-safe on VHE.
1290 	 */
1291 	if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1292 		     vcpu_get_flag(vcpu, INCREMENT_PC)))
1293 		kvm_call_hyp(__kvm_adjust_pc, vcpu);
1294 
1295 	vcpu_put(vcpu);
1296 	return ret;
1297 }
1298 
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1299 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1300 {
1301 	int bit_index;
1302 	bool set;
1303 	unsigned long *hcr;
1304 
1305 	if (number == KVM_ARM_IRQ_CPU_IRQ)
1306 		bit_index = __ffs(HCR_VI);
1307 	else /* KVM_ARM_IRQ_CPU_FIQ */
1308 		bit_index = __ffs(HCR_VF);
1309 
1310 	hcr = vcpu_hcr(vcpu);
1311 	if (level)
1312 		set = test_and_set_bit(bit_index, hcr);
1313 	else
1314 		set = test_and_clear_bit(bit_index, hcr);
1315 
1316 	/*
1317 	 * If we didn't change anything, no need to wake up or kick other CPUs
1318 	 */
1319 	if (set == level)
1320 		return 0;
1321 
1322 	/*
1323 	 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1324 	 * trigger a world-switch round on the running physical CPU to set the
1325 	 * virtual IRQ/FIQ fields in the HCR appropriately.
1326 	 */
1327 	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1328 	kvm_vcpu_kick(vcpu);
1329 
1330 	return 0;
1331 }
1332 
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1333 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1334 			  bool line_status)
1335 {
1336 	u32 irq = irq_level->irq;
1337 	unsigned int irq_type, vcpu_id, irq_num;
1338 	struct kvm_vcpu *vcpu = NULL;
1339 	bool level = irq_level->level;
1340 
1341 	irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1342 	vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1343 	vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1344 	irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1345 
1346 	trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
1347 
1348 	switch (irq_type) {
1349 	case KVM_ARM_IRQ_TYPE_CPU:
1350 		if (irqchip_in_kernel(kvm))
1351 			return -ENXIO;
1352 
1353 		vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1354 		if (!vcpu)
1355 			return -EINVAL;
1356 
1357 		if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1358 			return -EINVAL;
1359 
1360 		return vcpu_interrupt_line(vcpu, irq_num, level);
1361 	case KVM_ARM_IRQ_TYPE_PPI:
1362 		if (!irqchip_in_kernel(kvm))
1363 			return -ENXIO;
1364 
1365 		vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1366 		if (!vcpu)
1367 			return -EINVAL;
1368 
1369 		if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1370 			return -EINVAL;
1371 
1372 		return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
1373 	case KVM_ARM_IRQ_TYPE_SPI:
1374 		if (!irqchip_in_kernel(kvm))
1375 			return -ENXIO;
1376 
1377 		if (irq_num < VGIC_NR_PRIVATE_IRQS)
1378 			return -EINVAL;
1379 
1380 		return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
1381 	}
1382 
1383 	return -EINVAL;
1384 }
1385 
system_supported_vcpu_features(void)1386 static unsigned long system_supported_vcpu_features(void)
1387 {
1388 	unsigned long features = KVM_VCPU_VALID_FEATURES;
1389 
1390 	if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1))
1391 		clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features);
1392 
1393 	if (!kvm_arm_support_pmu_v3())
1394 		clear_bit(KVM_ARM_VCPU_PMU_V3, &features);
1395 
1396 	if (!system_supports_sve())
1397 		clear_bit(KVM_ARM_VCPU_SVE, &features);
1398 
1399 	if (!kvm_has_full_ptr_auth()) {
1400 		clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features);
1401 		clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features);
1402 	}
1403 
1404 	if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT))
1405 		clear_bit(KVM_ARM_VCPU_HAS_EL2, &features);
1406 
1407 	return features;
1408 }
1409 
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1410 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1411 					const struct kvm_vcpu_init *init)
1412 {
1413 	unsigned long features = init->features[0];
1414 	int i;
1415 
1416 	if (features & ~KVM_VCPU_VALID_FEATURES)
1417 		return -ENOENT;
1418 
1419 	for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1420 		if (init->features[i])
1421 			return -ENOENT;
1422 	}
1423 
1424 	if (features & ~system_supported_vcpu_features())
1425 		return -EINVAL;
1426 
1427 	/*
1428 	 * For now make sure that both address/generic pointer authentication
1429 	 * features are requested by the userspace together.
1430 	 */
1431 	if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) !=
1432 	    test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features))
1433 		return -EINVAL;
1434 
1435 	if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1436 		return 0;
1437 
1438 	/* MTE is incompatible with AArch32 */
1439 	if (kvm_has_mte(vcpu->kvm))
1440 		return -EINVAL;
1441 
1442 	/* NV is incompatible with AArch32 */
1443 	if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1444 		return -EINVAL;
1445 
1446 	return 0;
1447 }
1448 
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1449 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1450 				  const struct kvm_vcpu_init *init)
1451 {
1452 	unsigned long features = init->features[0];
1453 
1454 	return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,
1455 			     KVM_VCPU_MAX_FEATURES);
1456 }
1457 
kvm_setup_vcpu(struct kvm_vcpu * vcpu)1458 static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
1459 {
1460 	struct kvm *kvm = vcpu->kvm;
1461 	int ret = 0;
1462 
1463 	/*
1464 	 * When the vCPU has a PMU, but no PMU is set for the guest
1465 	 * yet, set the default one.
1466 	 */
1467 	if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu)
1468 		ret = kvm_arm_set_default_pmu(kvm);
1469 
1470 	/* Prepare for nested if required */
1471 	if (!ret && vcpu_has_nv(vcpu))
1472 		ret = kvm_vcpu_init_nested(vcpu);
1473 
1474 	return ret;
1475 }
1476 
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1477 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1478 				 const struct kvm_vcpu_init *init)
1479 {
1480 	unsigned long features = init->features[0];
1481 	struct kvm *kvm = vcpu->kvm;
1482 	int ret = -EINVAL;
1483 
1484 	mutex_lock(&kvm->arch.config_lock);
1485 
1486 	if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1487 	    kvm_vcpu_init_changed(vcpu, init))
1488 		goto out_unlock;
1489 
1490 	bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1491 
1492 	ret = kvm_setup_vcpu(vcpu);
1493 	if (ret)
1494 		goto out_unlock;
1495 
1496 	/* Now we know what it is, we can reset it. */
1497 	kvm_reset_vcpu(vcpu);
1498 
1499 	set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1500 	vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1501 	ret = 0;
1502 out_unlock:
1503 	mutex_unlock(&kvm->arch.config_lock);
1504 	return ret;
1505 }
1506 
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1507 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1508 			       const struct kvm_vcpu_init *init)
1509 {
1510 	int ret;
1511 
1512 	if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1513 	    init->target != kvm_target_cpu())
1514 		return -EINVAL;
1515 
1516 	ret = kvm_vcpu_init_check_features(vcpu, init);
1517 	if (ret)
1518 		return ret;
1519 
1520 	if (!kvm_vcpu_initialized(vcpu))
1521 		return __kvm_vcpu_set_target(vcpu, init);
1522 
1523 	if (kvm_vcpu_init_changed(vcpu, init))
1524 		return -EINVAL;
1525 
1526 	kvm_reset_vcpu(vcpu);
1527 	return 0;
1528 }
1529 
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1530 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1531 					 struct kvm_vcpu_init *init)
1532 {
1533 	bool power_off = false;
1534 	int ret;
1535 
1536 	/*
1537 	 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1538 	 * reflecting it in the finalized feature set, thus limiting its scope
1539 	 * to a single KVM_ARM_VCPU_INIT call.
1540 	 */
1541 	if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1542 		init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1543 		power_off = true;
1544 	}
1545 
1546 	ret = kvm_vcpu_set_target(vcpu, init);
1547 	if (ret)
1548 		return ret;
1549 
1550 	/*
1551 	 * Ensure a rebooted VM will fault in RAM pages and detect if the
1552 	 * guest MMU is turned off and flush the caches as needed.
1553 	 *
1554 	 * S2FWB enforces all memory accesses to RAM being cacheable,
1555 	 * ensuring that the data side is always coherent. We still
1556 	 * need to invalidate the I-cache though, as FWB does *not*
1557 	 * imply CTR_EL0.DIC.
1558 	 */
1559 	if (vcpu_has_run_once(vcpu)) {
1560 		if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1561 			stage2_unmap_vm(vcpu->kvm);
1562 		else
1563 			icache_inval_all_pou();
1564 	}
1565 
1566 	vcpu_reset_hcr(vcpu);
1567 
1568 	/*
1569 	 * Handle the "start in power-off" case.
1570 	 */
1571 	spin_lock(&vcpu->arch.mp_state_lock);
1572 
1573 	if (power_off)
1574 		__kvm_arm_vcpu_power_off(vcpu);
1575 	else
1576 		WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1577 
1578 	spin_unlock(&vcpu->arch.mp_state_lock);
1579 
1580 	return 0;
1581 }
1582 
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1583 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1584 				 struct kvm_device_attr *attr)
1585 {
1586 	int ret = -ENXIO;
1587 
1588 	switch (attr->group) {
1589 	default:
1590 		ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1591 		break;
1592 	}
1593 
1594 	return ret;
1595 }
1596 
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1597 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1598 				 struct kvm_device_attr *attr)
1599 {
1600 	int ret = -ENXIO;
1601 
1602 	switch (attr->group) {
1603 	default:
1604 		ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1605 		break;
1606 	}
1607 
1608 	return ret;
1609 }
1610 
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1611 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1612 				 struct kvm_device_attr *attr)
1613 {
1614 	int ret = -ENXIO;
1615 
1616 	switch (attr->group) {
1617 	default:
1618 		ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1619 		break;
1620 	}
1621 
1622 	return ret;
1623 }
1624 
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1625 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1626 				   struct kvm_vcpu_events *events)
1627 {
1628 	memset(events, 0, sizeof(*events));
1629 
1630 	return __kvm_arm_vcpu_get_events(vcpu, events);
1631 }
1632 
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1633 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1634 				   struct kvm_vcpu_events *events)
1635 {
1636 	int i;
1637 
1638 	/* check whether the reserved field is zero */
1639 	for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1640 		if (events->reserved[i])
1641 			return -EINVAL;
1642 
1643 	/* check whether the pad field is zero */
1644 	for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1645 		if (events->exception.pad[i])
1646 			return -EINVAL;
1647 
1648 	return __kvm_arm_vcpu_set_events(vcpu, events);
1649 }
1650 
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1651 long kvm_arch_vcpu_ioctl(struct file *filp,
1652 			 unsigned int ioctl, unsigned long arg)
1653 {
1654 	struct kvm_vcpu *vcpu = filp->private_data;
1655 	void __user *argp = (void __user *)arg;
1656 	struct kvm_device_attr attr;
1657 	long r;
1658 
1659 	switch (ioctl) {
1660 	case KVM_ARM_VCPU_INIT: {
1661 		struct kvm_vcpu_init init;
1662 
1663 		r = -EFAULT;
1664 		if (copy_from_user(&init, argp, sizeof(init)))
1665 			break;
1666 
1667 		r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1668 		break;
1669 	}
1670 	case KVM_SET_ONE_REG:
1671 	case KVM_GET_ONE_REG: {
1672 		struct kvm_one_reg reg;
1673 
1674 		r = -ENOEXEC;
1675 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1676 			break;
1677 
1678 		r = -EFAULT;
1679 		if (copy_from_user(&reg, argp, sizeof(reg)))
1680 			break;
1681 
1682 		/*
1683 		 * We could owe a reset due to PSCI. Handle the pending reset
1684 		 * here to ensure userspace register accesses are ordered after
1685 		 * the reset.
1686 		 */
1687 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1688 			kvm_reset_vcpu(vcpu);
1689 
1690 		if (ioctl == KVM_SET_ONE_REG)
1691 			r = kvm_arm_set_reg(vcpu, &reg);
1692 		else
1693 			r = kvm_arm_get_reg(vcpu, &reg);
1694 		break;
1695 	}
1696 	case KVM_GET_REG_LIST: {
1697 		struct kvm_reg_list __user *user_list = argp;
1698 		struct kvm_reg_list reg_list;
1699 		unsigned n;
1700 
1701 		r = -ENOEXEC;
1702 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1703 			break;
1704 
1705 		r = -EPERM;
1706 		if (!kvm_arm_vcpu_is_finalized(vcpu))
1707 			break;
1708 
1709 		r = -EFAULT;
1710 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1711 			break;
1712 		n = reg_list.n;
1713 		reg_list.n = kvm_arm_num_regs(vcpu);
1714 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1715 			break;
1716 		r = -E2BIG;
1717 		if (n < reg_list.n)
1718 			break;
1719 		r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1720 		break;
1721 	}
1722 	case KVM_SET_DEVICE_ATTR: {
1723 		r = -EFAULT;
1724 		if (copy_from_user(&attr, argp, sizeof(attr)))
1725 			break;
1726 		r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1727 		break;
1728 	}
1729 	case KVM_GET_DEVICE_ATTR: {
1730 		r = -EFAULT;
1731 		if (copy_from_user(&attr, argp, sizeof(attr)))
1732 			break;
1733 		r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1734 		break;
1735 	}
1736 	case KVM_HAS_DEVICE_ATTR: {
1737 		r = -EFAULT;
1738 		if (copy_from_user(&attr, argp, sizeof(attr)))
1739 			break;
1740 		r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1741 		break;
1742 	}
1743 	case KVM_GET_VCPU_EVENTS: {
1744 		struct kvm_vcpu_events events;
1745 
1746 		if (kvm_arm_vcpu_get_events(vcpu, &events))
1747 			return -EINVAL;
1748 
1749 		if (copy_to_user(argp, &events, sizeof(events)))
1750 			return -EFAULT;
1751 
1752 		return 0;
1753 	}
1754 	case KVM_SET_VCPU_EVENTS: {
1755 		struct kvm_vcpu_events events;
1756 
1757 		if (copy_from_user(&events, argp, sizeof(events)))
1758 			return -EFAULT;
1759 
1760 		return kvm_arm_vcpu_set_events(vcpu, &events);
1761 	}
1762 	case KVM_ARM_VCPU_FINALIZE: {
1763 		int what;
1764 
1765 		if (!kvm_vcpu_initialized(vcpu))
1766 			return -ENOEXEC;
1767 
1768 		if (get_user(what, (const int __user *)argp))
1769 			return -EFAULT;
1770 
1771 		return kvm_arm_vcpu_finalize(vcpu, what);
1772 	}
1773 	default:
1774 		r = -EINVAL;
1775 	}
1776 
1777 	return r;
1778 }
1779 
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1780 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1781 {
1782 
1783 }
1784 
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1785 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1786 					struct kvm_arm_device_addr *dev_addr)
1787 {
1788 	switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1789 	case KVM_ARM_DEVICE_VGIC_V2:
1790 		if (!vgic_present)
1791 			return -ENXIO;
1792 		return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1793 	default:
1794 		return -ENODEV;
1795 	}
1796 }
1797 
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1798 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1799 {
1800 	switch (attr->group) {
1801 	case KVM_ARM_VM_SMCCC_CTRL:
1802 		return kvm_vm_smccc_has_attr(kvm, attr);
1803 	default:
1804 		return -ENXIO;
1805 	}
1806 }
1807 
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1808 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1809 {
1810 	switch (attr->group) {
1811 	case KVM_ARM_VM_SMCCC_CTRL:
1812 		return kvm_vm_smccc_set_attr(kvm, attr);
1813 	default:
1814 		return -ENXIO;
1815 	}
1816 }
1817 
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1818 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1819 {
1820 	struct kvm *kvm = filp->private_data;
1821 	void __user *argp = (void __user *)arg;
1822 	struct kvm_device_attr attr;
1823 
1824 	switch (ioctl) {
1825 	case KVM_CREATE_IRQCHIP: {
1826 		int ret;
1827 		if (!vgic_present)
1828 			return -ENXIO;
1829 		mutex_lock(&kvm->lock);
1830 		ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1831 		mutex_unlock(&kvm->lock);
1832 		return ret;
1833 	}
1834 	case KVM_ARM_SET_DEVICE_ADDR: {
1835 		struct kvm_arm_device_addr dev_addr;
1836 
1837 		if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1838 			return -EFAULT;
1839 		return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1840 	}
1841 	case KVM_ARM_PREFERRED_TARGET: {
1842 		struct kvm_vcpu_init init = {
1843 			.target = KVM_ARM_TARGET_GENERIC_V8,
1844 		};
1845 
1846 		if (copy_to_user(argp, &init, sizeof(init)))
1847 			return -EFAULT;
1848 
1849 		return 0;
1850 	}
1851 	case KVM_ARM_MTE_COPY_TAGS: {
1852 		struct kvm_arm_copy_mte_tags copy_tags;
1853 
1854 		if (copy_from_user(&copy_tags, argp, sizeof(copy_tags)))
1855 			return -EFAULT;
1856 		return kvm_vm_ioctl_mte_copy_tags(kvm, &copy_tags);
1857 	}
1858 	case KVM_ARM_SET_COUNTER_OFFSET: {
1859 		struct kvm_arm_counter_offset offset;
1860 
1861 		if (copy_from_user(&offset, argp, sizeof(offset)))
1862 			return -EFAULT;
1863 		return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1864 	}
1865 	case KVM_HAS_DEVICE_ATTR: {
1866 		if (copy_from_user(&attr, argp, sizeof(attr)))
1867 			return -EFAULT;
1868 
1869 		return kvm_vm_has_attr(kvm, &attr);
1870 	}
1871 	case KVM_SET_DEVICE_ATTR: {
1872 		if (copy_from_user(&attr, argp, sizeof(attr)))
1873 			return -EFAULT;
1874 
1875 		return kvm_vm_set_attr(kvm, &attr);
1876 	}
1877 	case KVM_ARM_GET_REG_WRITABLE_MASKS: {
1878 		struct reg_mask_range range;
1879 
1880 		if (copy_from_user(&range, argp, sizeof(range)))
1881 			return -EFAULT;
1882 		return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range);
1883 	}
1884 	default:
1885 		return -EINVAL;
1886 	}
1887 }
1888 
1889 /* unlocks vcpus from @vcpu_lock_idx and smaller */
unlock_vcpus(struct kvm * kvm,int vcpu_lock_idx)1890 static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
1891 {
1892 	struct kvm_vcpu *tmp_vcpu;
1893 
1894 	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
1895 		tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
1896 		mutex_unlock(&tmp_vcpu->mutex);
1897 	}
1898 }
1899 
unlock_all_vcpus(struct kvm * kvm)1900 void unlock_all_vcpus(struct kvm *kvm)
1901 {
1902 	lockdep_assert_held(&kvm->lock);
1903 
1904 	unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
1905 }
1906 
1907 /* Returns true if all vcpus were locked, false otherwise */
lock_all_vcpus(struct kvm * kvm)1908 bool lock_all_vcpus(struct kvm *kvm)
1909 {
1910 	struct kvm_vcpu *tmp_vcpu;
1911 	unsigned long c;
1912 
1913 	lockdep_assert_held(&kvm->lock);
1914 
1915 	/*
1916 	 * Any time a vcpu is in an ioctl (including running), the
1917 	 * core KVM code tries to grab the vcpu->mutex.
1918 	 *
1919 	 * By grabbing the vcpu->mutex of all VCPUs we ensure that no
1920 	 * other VCPUs can fiddle with the state while we access it.
1921 	 */
1922 	kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
1923 		if (!mutex_trylock(&tmp_vcpu->mutex)) {
1924 			unlock_vcpus(kvm, c - 1);
1925 			return false;
1926 		}
1927 	}
1928 
1929 	return true;
1930 }
1931 
nvhe_percpu_size(void)1932 static unsigned long nvhe_percpu_size(void)
1933 {
1934 	return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1935 		(unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1936 }
1937 
nvhe_percpu_order(void)1938 static unsigned long nvhe_percpu_order(void)
1939 {
1940 	unsigned long size = nvhe_percpu_size();
1941 
1942 	return size ? get_order(size) : 0;
1943 }
1944 
pkvm_host_sve_state_order(void)1945 static size_t pkvm_host_sve_state_order(void)
1946 {
1947 	return get_order(pkvm_host_sve_state_size());
1948 }
1949 
1950 /* A lookup table holding the hypervisor VA for each vector slot */
1951 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1952 
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1953 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1954 {
1955 	hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1956 }
1957 
kvm_init_vector_slots(void)1958 static int kvm_init_vector_slots(void)
1959 {
1960 	int err;
1961 	void *base;
1962 
1963 	base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1964 	kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1965 
1966 	base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1967 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1968 
1969 	if (kvm_system_needs_idmapped_vectors() &&
1970 	    !is_protected_kvm_enabled()) {
1971 		err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1972 					       __BP_HARDEN_HYP_VECS_SZ, &base);
1973 		if (err)
1974 			return err;
1975 	}
1976 
1977 	kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1978 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1979 	return 0;
1980 }
1981 
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1982 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1983 {
1984 	struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1985 	unsigned long tcr;
1986 
1987 	/*
1988 	 * Calculate the raw per-cpu offset without a translation from the
1989 	 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1990 	 * so that we can use adr_l to access per-cpu variables in EL2.
1991 	 * Also drop the KASAN tag which gets in the way...
1992 	 */
1993 	params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1994 			    (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1995 
1996 	params->mair_el2 = read_sysreg(mair_el1);
1997 
1998 	tcr = read_sysreg(tcr_el1);
1999 	if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
2000 		tcr &= ~(TCR_HD | TCR_HA | TCR_A1 | TCR_T0SZ_MASK);
2001 		tcr |= TCR_EPD1_MASK;
2002 	} else {
2003 		unsigned long ips = FIELD_GET(TCR_IPS_MASK, tcr);
2004 
2005 		tcr &= TCR_EL2_MASK;
2006 		tcr |= TCR_EL2_RES1 | FIELD_PREP(TCR_EL2_PS_MASK, ips);
2007 		if (lpa2_is_enabled())
2008 			tcr |= TCR_EL2_DS;
2009 	}
2010 	tcr |= TCR_T0SZ(hyp_va_bits);
2011 	params->tcr_el2 = tcr;
2012 
2013 	params->pgd_pa = kvm_mmu_get_httbr();
2014 	if (is_protected_kvm_enabled())
2015 		params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
2016 	else
2017 		params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
2018 	if (cpus_have_final_cap(ARM64_KVM_HVHE))
2019 		params->hcr_el2 |= HCR_E2H;
2020 	params->vttbr = params->vtcr = 0;
2021 
2022 	/*
2023 	 * Flush the init params from the data cache because the struct will
2024 	 * be read while the MMU is off.
2025 	 */
2026 	kvm_flush_dcache_to_poc(params, sizeof(*params));
2027 }
2028 
hyp_install_host_vector(void)2029 static void hyp_install_host_vector(void)
2030 {
2031 	struct kvm_nvhe_init_params *params;
2032 	struct arm_smccc_res res;
2033 
2034 	/* Switch from the HYP stub to our own HYP init vector */
2035 	__hyp_set_vectors(kvm_get_idmap_vector());
2036 
2037 	/*
2038 	 * Call initialization code, and switch to the full blown HYP code.
2039 	 * If the cpucaps haven't been finalized yet, something has gone very
2040 	 * wrong, and hyp will crash and burn when it uses any
2041 	 * cpus_have_*_cap() wrapper.
2042 	 */
2043 	BUG_ON(!system_capabilities_finalized());
2044 	params = this_cpu_ptr_nvhe_sym(kvm_init_params);
2045 	arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
2046 	WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
2047 }
2048 
cpu_init_hyp_mode(void)2049 static void cpu_init_hyp_mode(void)
2050 {
2051 	hyp_install_host_vector();
2052 
2053 	/*
2054 	 * Disabling SSBD on a non-VHE system requires us to enable SSBS
2055 	 * at EL2.
2056 	 */
2057 	if (this_cpu_has_cap(ARM64_SSBS) &&
2058 	    arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
2059 		kvm_call_hyp_nvhe(__kvm_enable_ssbs);
2060 	}
2061 }
2062 
cpu_hyp_reset(void)2063 static void cpu_hyp_reset(void)
2064 {
2065 	if (!is_kernel_in_hyp_mode())
2066 		__hyp_reset_vectors();
2067 }
2068 
2069 /*
2070  * EL2 vectors can be mapped and rerouted in a number of ways,
2071  * depending on the kernel configuration and CPU present:
2072  *
2073  * - If the CPU is affected by Spectre-v2, the hardening sequence is
2074  *   placed in one of the vector slots, which is executed before jumping
2075  *   to the real vectors.
2076  *
2077  * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
2078  *   containing the hardening sequence is mapped next to the idmap page,
2079  *   and executed before jumping to the real vectors.
2080  *
2081  * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
2082  *   empty slot is selected, mapped next to the idmap page, and
2083  *   executed before jumping to the real vectors.
2084  *
2085  * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
2086  * VHE, as we don't have hypervisor-specific mappings. If the system
2087  * is VHE and yet selects this capability, it will be ignored.
2088  */
cpu_set_hyp_vector(void)2089 static void cpu_set_hyp_vector(void)
2090 {
2091 	struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
2092 	void *vector = hyp_spectre_vector_selector[data->slot];
2093 
2094 	if (!is_protected_kvm_enabled())
2095 		*this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
2096 	else
2097 		kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
2098 }
2099 
cpu_hyp_init_context(void)2100 static void cpu_hyp_init_context(void)
2101 {
2102 	kvm_init_host_cpu_context(host_data_ptr(host_ctxt));
2103 	kvm_init_host_debug_data();
2104 
2105 	if (!is_kernel_in_hyp_mode())
2106 		cpu_init_hyp_mode();
2107 }
2108 
cpu_hyp_init_features(void)2109 static void cpu_hyp_init_features(void)
2110 {
2111 	cpu_set_hyp_vector();
2112 
2113 	if (is_kernel_in_hyp_mode())
2114 		kvm_timer_init_vhe();
2115 
2116 	if (vgic_present)
2117 		kvm_vgic_init_cpu_hardware();
2118 }
2119 
cpu_hyp_reinit(void)2120 static void cpu_hyp_reinit(void)
2121 {
2122 	cpu_hyp_reset();
2123 	cpu_hyp_init_context();
2124 	cpu_hyp_init_features();
2125 }
2126 
cpu_hyp_init(void * discard)2127 static void cpu_hyp_init(void *discard)
2128 {
2129 	if (!__this_cpu_read(kvm_hyp_initialized)) {
2130 		cpu_hyp_reinit();
2131 		__this_cpu_write(kvm_hyp_initialized, 1);
2132 	}
2133 }
2134 
cpu_hyp_uninit(void * discard)2135 static void cpu_hyp_uninit(void *discard)
2136 {
2137 	if (__this_cpu_read(kvm_hyp_initialized)) {
2138 		cpu_hyp_reset();
2139 		__this_cpu_write(kvm_hyp_initialized, 0);
2140 	}
2141 }
2142 
kvm_arch_enable_virtualization_cpu(void)2143 int kvm_arch_enable_virtualization_cpu(void)
2144 {
2145 	/*
2146 	 * Most calls to this function are made with migration
2147 	 * disabled, but not with preemption disabled. The former is
2148 	 * enough to ensure correctness, but most of the helpers
2149 	 * expect the later and will throw a tantrum otherwise.
2150 	 */
2151 	preempt_disable();
2152 
2153 	cpu_hyp_init(NULL);
2154 
2155 	kvm_vgic_cpu_up();
2156 	kvm_timer_cpu_up();
2157 
2158 	preempt_enable();
2159 
2160 	return 0;
2161 }
2162 
kvm_arch_disable_virtualization_cpu(void)2163 void kvm_arch_disable_virtualization_cpu(void)
2164 {
2165 	kvm_timer_cpu_down();
2166 	kvm_vgic_cpu_down();
2167 
2168 	if (!is_protected_kvm_enabled())
2169 		cpu_hyp_uninit(NULL);
2170 }
2171 
2172 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2173 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2174 				    unsigned long cmd,
2175 				    void *v)
2176 {
2177 	/*
2178 	 * kvm_hyp_initialized is left with its old value over
2179 	 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2180 	 * re-enable hyp.
2181 	 */
2182 	switch (cmd) {
2183 	case CPU_PM_ENTER:
2184 		if (__this_cpu_read(kvm_hyp_initialized))
2185 			/*
2186 			 * don't update kvm_hyp_initialized here
2187 			 * so that the hyp will be re-enabled
2188 			 * when we resume. See below.
2189 			 */
2190 			cpu_hyp_reset();
2191 
2192 		return NOTIFY_OK;
2193 	case CPU_PM_ENTER_FAILED:
2194 	case CPU_PM_EXIT:
2195 		if (__this_cpu_read(kvm_hyp_initialized))
2196 			/* The hyp was enabled before suspend. */
2197 			cpu_hyp_reinit();
2198 
2199 		return NOTIFY_OK;
2200 
2201 	default:
2202 		return NOTIFY_DONE;
2203 	}
2204 }
2205 
2206 static struct notifier_block hyp_init_cpu_pm_nb = {
2207 	.notifier_call = hyp_init_cpu_pm_notifier,
2208 };
2209 
hyp_cpu_pm_init(void)2210 static void __init hyp_cpu_pm_init(void)
2211 {
2212 	if (!is_protected_kvm_enabled())
2213 		cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2214 }
hyp_cpu_pm_exit(void)2215 static void __init hyp_cpu_pm_exit(void)
2216 {
2217 	if (!is_protected_kvm_enabled())
2218 		cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2219 }
2220 #else
hyp_cpu_pm_init(void)2221 static inline void __init hyp_cpu_pm_init(void)
2222 {
2223 }
hyp_cpu_pm_exit(void)2224 static inline void __init hyp_cpu_pm_exit(void)
2225 {
2226 }
2227 #endif
2228 
init_cpu_logical_map(void)2229 static void __init init_cpu_logical_map(void)
2230 {
2231 	unsigned int cpu;
2232 
2233 	/*
2234 	 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2235 	 * Only copy the set of online CPUs whose features have been checked
2236 	 * against the finalized system capabilities. The hypervisor will not
2237 	 * allow any other CPUs from the `possible` set to boot.
2238 	 */
2239 	for_each_online_cpu(cpu)
2240 		hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2241 }
2242 
2243 #define init_psci_0_1_impl_state(config, what)	\
2244 	config.psci_0_1_ ## what ## _implemented = psci_ops.what
2245 
init_psci_relay(void)2246 static bool __init init_psci_relay(void)
2247 {
2248 	/*
2249 	 * If PSCI has not been initialized, protected KVM cannot install
2250 	 * itself on newly booted CPUs.
2251 	 */
2252 	if (!psci_ops.get_version) {
2253 		kvm_err("Cannot initialize protected mode without PSCI\n");
2254 		return false;
2255 	}
2256 
2257 	kvm_host_psci_config.version = psci_ops.get_version();
2258 	kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2259 
2260 	if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2261 		kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2262 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2263 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2264 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2265 		init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2266 	}
2267 	return true;
2268 }
2269 
init_subsystems(void)2270 static int __init init_subsystems(void)
2271 {
2272 	int err = 0;
2273 
2274 	/*
2275 	 * Enable hardware so that subsystem initialisation can access EL2.
2276 	 */
2277 	on_each_cpu(cpu_hyp_init, NULL, 1);
2278 
2279 	/*
2280 	 * Register CPU lower-power notifier
2281 	 */
2282 	hyp_cpu_pm_init();
2283 
2284 	/*
2285 	 * Init HYP view of VGIC
2286 	 */
2287 	err = kvm_vgic_hyp_init();
2288 	switch (err) {
2289 	case 0:
2290 		vgic_present = true;
2291 		break;
2292 	case -ENODEV:
2293 	case -ENXIO:
2294 		/*
2295 		 * No VGIC? No pKVM for you.
2296 		 *
2297 		 * Protected mode assumes that VGICv3 is present, so no point
2298 		 * in trying to hobble along if vgic initialization fails.
2299 		 */
2300 		if (is_protected_kvm_enabled())
2301 			goto out;
2302 
2303 		/*
2304 		 * Otherwise, userspace could choose to implement a GIC for its
2305 		 * guest on non-cooperative hardware.
2306 		 */
2307 		vgic_present = false;
2308 		err = 0;
2309 		break;
2310 	default:
2311 		goto out;
2312 	}
2313 
2314 	/*
2315 	 * Init HYP architected timer support
2316 	 */
2317 	err = kvm_timer_hyp_init(vgic_present);
2318 	if (err)
2319 		goto out;
2320 
2321 	kvm_register_perf_callbacks(NULL);
2322 
2323 out:
2324 	if (err)
2325 		hyp_cpu_pm_exit();
2326 
2327 	if (err || !is_protected_kvm_enabled())
2328 		on_each_cpu(cpu_hyp_uninit, NULL, 1);
2329 
2330 	return err;
2331 }
2332 
teardown_subsystems(void)2333 static void __init teardown_subsystems(void)
2334 {
2335 	kvm_unregister_perf_callbacks();
2336 	hyp_cpu_pm_exit();
2337 }
2338 
teardown_hyp_mode(void)2339 static void __init teardown_hyp_mode(void)
2340 {
2341 	bool free_sve = system_supports_sve() && is_protected_kvm_enabled();
2342 	int cpu;
2343 
2344 	free_hyp_pgds();
2345 	for_each_possible_cpu(cpu) {
2346 		free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2347 		free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2348 
2349 		if (free_sve) {
2350 			struct cpu_sve_state *sve_state;
2351 
2352 			sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2353 			free_pages((unsigned long) sve_state, pkvm_host_sve_state_order());
2354 		}
2355 	}
2356 }
2357 
do_pkvm_init(u32 hyp_va_bits)2358 static int __init do_pkvm_init(u32 hyp_va_bits)
2359 {
2360 	void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2361 	int ret;
2362 
2363 	preempt_disable();
2364 	cpu_hyp_init_context();
2365 	ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2366 				num_possible_cpus(), kern_hyp_va(per_cpu_base),
2367 				hyp_va_bits);
2368 	cpu_hyp_init_features();
2369 
2370 	/*
2371 	 * The stub hypercalls are now disabled, so set our local flag to
2372 	 * prevent a later re-init attempt in kvm_arch_enable_virtualization_cpu().
2373 	 */
2374 	__this_cpu_write(kvm_hyp_initialized, 1);
2375 	preempt_enable();
2376 
2377 	return ret;
2378 }
2379 
get_hyp_id_aa64pfr0_el1(void)2380 static u64 get_hyp_id_aa64pfr0_el1(void)
2381 {
2382 	/*
2383 	 * Track whether the system isn't affected by spectre/meltdown in the
2384 	 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2385 	 * Although this is per-CPU, we make it global for simplicity, e.g., not
2386 	 * to have to worry about vcpu migration.
2387 	 *
2388 	 * Unlike for non-protected VMs, userspace cannot override this for
2389 	 * protected VMs.
2390 	 */
2391 	u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2392 
2393 	val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
2394 		 ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
2395 
2396 	val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2),
2397 			  arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2398 	val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3),
2399 			  arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2400 
2401 	return val;
2402 }
2403 
kvm_hyp_init_symbols(void)2404 static void kvm_hyp_init_symbols(void)
2405 {
2406 	kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2407 	kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2408 	kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2409 	kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2410 	kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2411 	kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2412 	kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2413 	kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2414 	kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2415 	kvm_nvhe_sym(__icache_flags) = __icache_flags;
2416 	kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2417 
2418 	/*
2419 	 * Flush entire BSS since part of its data containing init symbols is read
2420 	 * while the MMU is off.
2421 	 */
2422 	kvm_flush_dcache_to_poc(kvm_ksym_ref(__hyp_bss_start),
2423 				kvm_ksym_ref(__hyp_bss_end) - kvm_ksym_ref(__hyp_bss_start));
2424 }
2425 
kvm_hyp_init_protection(u32 hyp_va_bits)2426 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2427 {
2428 	void *addr = phys_to_virt(hyp_mem_base);
2429 	int ret;
2430 
2431 	ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2432 	if (ret)
2433 		return ret;
2434 
2435 	ret = do_pkvm_init(hyp_va_bits);
2436 	if (ret)
2437 		return ret;
2438 
2439 	free_hyp_pgds();
2440 
2441 	return 0;
2442 }
2443 
init_pkvm_host_sve_state(void)2444 static int init_pkvm_host_sve_state(void)
2445 {
2446 	int cpu;
2447 
2448 	if (!system_supports_sve())
2449 		return 0;
2450 
2451 	/* Allocate pages for host sve state in protected mode. */
2452 	for_each_possible_cpu(cpu) {
2453 		struct page *page = alloc_pages(GFP_KERNEL, pkvm_host_sve_state_order());
2454 
2455 		if (!page)
2456 			return -ENOMEM;
2457 
2458 		per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state = page_address(page);
2459 	}
2460 
2461 	/*
2462 	 * Don't map the pages in hyp since these are only used in protected
2463 	 * mode, which will (re)create its own mapping when initialized.
2464 	 */
2465 
2466 	return 0;
2467 }
2468 
2469 /*
2470  * Finalizes the initialization of hyp mode, once everything else is initialized
2471  * and the initialziation process cannot fail.
2472  */
finalize_init_hyp_mode(void)2473 static void finalize_init_hyp_mode(void)
2474 {
2475 	int cpu;
2476 
2477 	if (system_supports_sve() && is_protected_kvm_enabled()) {
2478 		for_each_possible_cpu(cpu) {
2479 			struct cpu_sve_state *sve_state;
2480 
2481 			sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2482 			per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state =
2483 				kern_hyp_va(sve_state);
2484 		}
2485 	}
2486 }
2487 
pkvm_hyp_init_ptrauth(void)2488 static void pkvm_hyp_init_ptrauth(void)
2489 {
2490 	struct kvm_cpu_context *hyp_ctxt;
2491 	int cpu;
2492 
2493 	for_each_possible_cpu(cpu) {
2494 		hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2495 		hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2496 		hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2497 		hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2498 		hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2499 		hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2500 		hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2501 		hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2502 		hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2503 		hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2504 		hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2505 	}
2506 }
2507 
2508 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2509 static int __init init_hyp_mode(void)
2510 {
2511 	u32 hyp_va_bits;
2512 	int cpu;
2513 	int err = -ENOMEM;
2514 
2515 	/*
2516 	 * The protected Hyp-mode cannot be initialized if the memory pool
2517 	 * allocation has failed.
2518 	 */
2519 	if (is_protected_kvm_enabled() && !hyp_mem_base)
2520 		goto out_err;
2521 
2522 	/*
2523 	 * Allocate Hyp PGD and setup Hyp identity mapping
2524 	 */
2525 	err = kvm_mmu_init(&hyp_va_bits);
2526 	if (err)
2527 		goto out_err;
2528 
2529 	/*
2530 	 * Allocate stack pages for Hypervisor-mode
2531 	 */
2532 	for_each_possible_cpu(cpu) {
2533 		unsigned long stack_base;
2534 
2535 		stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2536 		if (!stack_base) {
2537 			err = -ENOMEM;
2538 			goto out_err;
2539 		}
2540 
2541 		per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2542 	}
2543 
2544 	/*
2545 	 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2546 	 */
2547 	for_each_possible_cpu(cpu) {
2548 		struct page *page;
2549 		void *page_addr;
2550 
2551 		page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2552 		if (!page) {
2553 			err = -ENOMEM;
2554 			goto out_err;
2555 		}
2556 
2557 		page_addr = page_address(page);
2558 		memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2559 		kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2560 	}
2561 
2562 	/*
2563 	 * Map the Hyp-code called directly from the host
2564 	 */
2565 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2566 				  kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2567 	if (err) {
2568 		kvm_err("Cannot map world-switch code\n");
2569 		goto out_err;
2570 	}
2571 
2572 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2573 				  kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2574 	if (err) {
2575 		kvm_err("Cannot map .hyp.rodata section\n");
2576 		goto out_err;
2577 	}
2578 
2579 	err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2580 				  kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2581 	if (err) {
2582 		kvm_err("Cannot map rodata section\n");
2583 		goto out_err;
2584 	}
2585 
2586 	/*
2587 	 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2588 	 * section thanks to an assertion in the linker script. Map it RW and
2589 	 * the rest of .bss RO.
2590 	 */
2591 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2592 				  kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2593 	if (err) {
2594 		kvm_err("Cannot map hyp bss section: %d\n", err);
2595 		goto out_err;
2596 	}
2597 
2598 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2599 				  kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2600 	if (err) {
2601 		kvm_err("Cannot map bss section\n");
2602 		goto out_err;
2603 	}
2604 
2605 	/*
2606 	 * Map the Hyp stack pages
2607 	 */
2608 	for_each_possible_cpu(cpu) {
2609 		struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2610 		char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2611 
2612 		err = create_hyp_stack(__pa(stack_base), &params->stack_hyp_va);
2613 		if (err) {
2614 			kvm_err("Cannot map hyp stack\n");
2615 			goto out_err;
2616 		}
2617 
2618 		/*
2619 		 * Save the stack PA in nvhe_init_params. This will be needed
2620 		 * to recreate the stack mapping in protected nVHE mode.
2621 		 * __hyp_pa() won't do the right thing there, since the stack
2622 		 * has been mapped in the flexible private VA space.
2623 		 */
2624 		params->stack_pa = __pa(stack_base);
2625 	}
2626 
2627 	for_each_possible_cpu(cpu) {
2628 		char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2629 		char *percpu_end = percpu_begin + nvhe_percpu_size();
2630 
2631 		/* Map Hyp percpu pages */
2632 		err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2633 		if (err) {
2634 			kvm_err("Cannot map hyp percpu region\n");
2635 			goto out_err;
2636 		}
2637 
2638 		/* Prepare the CPU initialization parameters */
2639 		cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2640 	}
2641 
2642 	kvm_hyp_init_symbols();
2643 
2644 	if (is_protected_kvm_enabled()) {
2645 		if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2646 		    cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH))
2647 			pkvm_hyp_init_ptrauth();
2648 
2649 		init_cpu_logical_map();
2650 
2651 		if (!init_psci_relay()) {
2652 			err = -ENODEV;
2653 			goto out_err;
2654 		}
2655 
2656 		err = init_pkvm_host_sve_state();
2657 		if (err)
2658 			goto out_err;
2659 
2660 		err = kvm_hyp_init_protection(hyp_va_bits);
2661 		if (err) {
2662 			kvm_err("Failed to init hyp memory protection\n");
2663 			goto out_err;
2664 		}
2665 	}
2666 
2667 	return 0;
2668 
2669 out_err:
2670 	teardown_hyp_mode();
2671 	kvm_err("error initializing Hyp mode: %d\n", err);
2672 	return err;
2673 }
2674 
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2675 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2676 {
2677 	struct kvm_vcpu *vcpu = NULL;
2678 	struct kvm_mpidr_data *data;
2679 	unsigned long i;
2680 
2681 	mpidr &= MPIDR_HWID_BITMASK;
2682 
2683 	rcu_read_lock();
2684 	data = rcu_dereference(kvm->arch.mpidr_data);
2685 
2686 	if (data) {
2687 		u16 idx = kvm_mpidr_index(data, mpidr);
2688 
2689 		vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]);
2690 		if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu))
2691 			vcpu = NULL;
2692 	}
2693 
2694 	rcu_read_unlock();
2695 
2696 	if (vcpu)
2697 		return vcpu;
2698 
2699 	kvm_for_each_vcpu(i, vcpu, kvm) {
2700 		if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2701 			return vcpu;
2702 	}
2703 	return NULL;
2704 }
2705 
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2706 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2707 {
2708 	return irqchip_in_kernel(kvm);
2709 }
2710 
kvm_arch_has_irq_bypass(void)2711 bool kvm_arch_has_irq_bypass(void)
2712 {
2713 	return true;
2714 }
2715 
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2716 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2717 				      struct irq_bypass_producer *prod)
2718 {
2719 	struct kvm_kernel_irqfd *irqfd =
2720 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2721 
2722 	return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2723 					  &irqfd->irq_entry);
2724 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2725 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2726 				      struct irq_bypass_producer *prod)
2727 {
2728 	struct kvm_kernel_irqfd *irqfd =
2729 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2730 
2731 	kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2732 				     &irqfd->irq_entry);
2733 }
2734 
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2735 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2736 {
2737 	struct kvm_kernel_irqfd *irqfd =
2738 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2739 
2740 	kvm_arm_halt_guest(irqfd->kvm);
2741 }
2742 
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2743 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2744 {
2745 	struct kvm_kernel_irqfd *irqfd =
2746 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2747 
2748 	kvm_arm_resume_guest(irqfd->kvm);
2749 }
2750 
2751 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2752 static __init int kvm_arm_init(void)
2753 {
2754 	int err;
2755 	bool in_hyp_mode;
2756 
2757 	if (!is_hyp_mode_available()) {
2758 		kvm_info("HYP mode not available\n");
2759 		return -ENODEV;
2760 	}
2761 
2762 	if (kvm_get_mode() == KVM_MODE_NONE) {
2763 		kvm_info("KVM disabled from command line\n");
2764 		return -ENODEV;
2765 	}
2766 
2767 	err = kvm_sys_reg_table_init();
2768 	if (err) {
2769 		kvm_info("Error initializing system register tables");
2770 		return err;
2771 	}
2772 
2773 	in_hyp_mode = is_kernel_in_hyp_mode();
2774 
2775 	if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2776 	    cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2777 		kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2778 			 "Only trusted guests should be used on this system.\n");
2779 
2780 	err = kvm_set_ipa_limit();
2781 	if (err)
2782 		return err;
2783 
2784 	err = kvm_arm_init_sve();
2785 	if (err)
2786 		return err;
2787 
2788 	err = kvm_arm_vmid_alloc_init();
2789 	if (err) {
2790 		kvm_err("Failed to initialize VMID allocator.\n");
2791 		return err;
2792 	}
2793 
2794 	if (!in_hyp_mode) {
2795 		err = init_hyp_mode();
2796 		if (err)
2797 			goto out_err;
2798 	}
2799 
2800 	err = kvm_init_vector_slots();
2801 	if (err) {
2802 		kvm_err("Cannot initialise vector slots\n");
2803 		goto out_hyp;
2804 	}
2805 
2806 	err = init_subsystems();
2807 	if (err)
2808 		goto out_hyp;
2809 
2810 	kvm_info("%s%sVHE mode initialized successfully\n",
2811 		 in_hyp_mode ? "" : (is_protected_kvm_enabled() ?
2812 				     "Protected " : "Hyp "),
2813 		 in_hyp_mode ? "" : (cpus_have_final_cap(ARM64_KVM_HVHE) ?
2814 				     "h" : "n"));
2815 
2816 	/*
2817 	 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2818 	 * hypervisor protection is finalized.
2819 	 */
2820 	err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2821 	if (err)
2822 		goto out_subs;
2823 
2824 	/*
2825 	 * This should be called after initialization is done and failure isn't
2826 	 * possible anymore.
2827 	 */
2828 	if (!in_hyp_mode)
2829 		finalize_init_hyp_mode();
2830 
2831 	kvm_arm_initialised = true;
2832 
2833 	return 0;
2834 
2835 out_subs:
2836 	teardown_subsystems();
2837 out_hyp:
2838 	if (!in_hyp_mode)
2839 		teardown_hyp_mode();
2840 out_err:
2841 	kvm_arm_vmid_alloc_free();
2842 	return err;
2843 }
2844 
early_kvm_mode_cfg(char * arg)2845 static int __init early_kvm_mode_cfg(char *arg)
2846 {
2847 	if (!arg)
2848 		return -EINVAL;
2849 
2850 	if (strcmp(arg, "none") == 0) {
2851 		kvm_mode = KVM_MODE_NONE;
2852 		return 0;
2853 	}
2854 
2855 	if (!is_hyp_mode_available()) {
2856 		pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2857 		return 0;
2858 	}
2859 
2860 	if (strcmp(arg, "protected") == 0) {
2861 		if (!is_kernel_in_hyp_mode())
2862 			kvm_mode = KVM_MODE_PROTECTED;
2863 		else
2864 			pr_warn_once("Protected KVM not available with VHE\n");
2865 
2866 		return 0;
2867 	}
2868 
2869 	if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2870 		kvm_mode = KVM_MODE_DEFAULT;
2871 		return 0;
2872 	}
2873 
2874 	if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2875 		kvm_mode = KVM_MODE_NV;
2876 		return 0;
2877 	}
2878 
2879 	return -EINVAL;
2880 }
2881 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2882 
early_kvm_wfx_trap_policy_cfg(char * arg,enum kvm_wfx_trap_policy * p)2883 static int __init early_kvm_wfx_trap_policy_cfg(char *arg, enum kvm_wfx_trap_policy *p)
2884 {
2885 	if (!arg)
2886 		return -EINVAL;
2887 
2888 	if (strcmp(arg, "trap") == 0) {
2889 		*p = KVM_WFX_TRAP;
2890 		return 0;
2891 	}
2892 
2893 	if (strcmp(arg, "notrap") == 0) {
2894 		*p = KVM_WFX_NOTRAP;
2895 		return 0;
2896 	}
2897 
2898 	return -EINVAL;
2899 }
2900 
early_kvm_wfi_trap_policy_cfg(char * arg)2901 static int __init early_kvm_wfi_trap_policy_cfg(char *arg)
2902 {
2903 	return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfi_trap_policy);
2904 }
2905 early_param("kvm-arm.wfi_trap_policy", early_kvm_wfi_trap_policy_cfg);
2906 
early_kvm_wfe_trap_policy_cfg(char * arg)2907 static int __init early_kvm_wfe_trap_policy_cfg(char *arg)
2908 {
2909 	return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfe_trap_policy);
2910 }
2911 early_param("kvm-arm.wfe_trap_policy", early_kvm_wfe_trap_policy_cfg);
2912 
kvm_get_mode(void)2913 enum kvm_mode kvm_get_mode(void)
2914 {
2915 	return kvm_mode;
2916 }
2917 
2918 module_init(kvm_arm_init);
2919