xref: /linux/arch/arm64/kvm/arm.c (revision 209cd6f2ca94fab1331b9aa58dc9a17c7fc1f550)
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/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 	return kvm_share_hyp(vcpu, vcpu + 1);
470 }
471 
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)472 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
473 {
474 }
475 
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)476 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
477 {
478 	if (!is_protected_kvm_enabled())
479 		kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
480 	else
481 		free_hyp_memcache(&vcpu->arch.pkvm_memcache);
482 	kvm_timer_vcpu_terminate(vcpu);
483 	kvm_pmu_vcpu_destroy(vcpu);
484 	kvm_vgic_vcpu_destroy(vcpu);
485 	kvm_arm_vcpu_destroy(vcpu);
486 }
487 
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)488 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
489 {
490 
491 }
492 
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)493 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
494 {
495 
496 }
497 
vcpu_set_pauth_traps(struct kvm_vcpu * vcpu)498 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
499 {
500 	if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
501 		/*
502 		 * Either we're running an L2 guest, and the API/APK bits come
503 		 * from L1's HCR_EL2, or API/APK are both set.
504 		 */
505 		if (unlikely(vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu))) {
506 			u64 val;
507 
508 			val = __vcpu_sys_reg(vcpu, HCR_EL2);
509 			val &= (HCR_API | HCR_APK);
510 			vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
511 			vcpu->arch.hcr_el2 |= val;
512 		} else {
513 			vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
514 		}
515 
516 		/*
517 		 * Save the host keys if there is any chance for the guest
518 		 * to use pauth, as the entry code will reload the guest
519 		 * keys in that case.
520 		 */
521 		if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
522 			struct kvm_cpu_context *ctxt;
523 
524 			ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
525 			ptrauth_save_keys(ctxt);
526 		}
527 	}
528 }
529 
kvm_vcpu_should_clear_twi(struct kvm_vcpu * vcpu)530 static bool kvm_vcpu_should_clear_twi(struct kvm_vcpu *vcpu)
531 {
532 	if (unlikely(kvm_wfi_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
533 		return kvm_wfi_trap_policy == KVM_WFX_NOTRAP;
534 
535 	return single_task_running() &&
536 	       (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
537 		vcpu->kvm->arch.vgic.nassgireq);
538 }
539 
kvm_vcpu_should_clear_twe(struct kvm_vcpu * vcpu)540 static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu)
541 {
542 	if (unlikely(kvm_wfe_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
543 		return kvm_wfe_trap_policy == KVM_WFX_NOTRAP;
544 
545 	return single_task_running();
546 }
547 
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)548 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
549 {
550 	struct kvm_s2_mmu *mmu;
551 	int *last_ran;
552 
553 	if (is_protected_kvm_enabled())
554 		goto nommu;
555 
556 	if (vcpu_has_nv(vcpu))
557 		kvm_vcpu_load_hw_mmu(vcpu);
558 
559 	mmu = vcpu->arch.hw_mmu;
560 	last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
561 
562 	/*
563 	 * Ensure a VMID is allocated for the MMU before programming VTTBR_EL2,
564 	 * which happens eagerly in VHE.
565 	 *
566 	 * Also, the VMID allocator only preserves VMIDs that are active at the
567 	 * time of rollover, so KVM might need to grab a new VMID for the MMU if
568 	 * this is called from kvm_sched_in().
569 	 */
570 	kvm_arm_vmid_update(&mmu->vmid);
571 
572 	/*
573 	 * We guarantee that both TLBs and I-cache are private to each
574 	 * vcpu. If detecting that a vcpu from the same VM has
575 	 * previously run on the same physical CPU, call into the
576 	 * hypervisor code to nuke the relevant contexts.
577 	 *
578 	 * We might get preempted before the vCPU actually runs, but
579 	 * over-invalidation doesn't affect correctness.
580 	 */
581 	if (*last_ran != vcpu->vcpu_idx) {
582 		kvm_call_hyp(__kvm_flush_cpu_context, mmu);
583 		*last_ran = vcpu->vcpu_idx;
584 	}
585 
586 nommu:
587 	vcpu->cpu = cpu;
588 
589 	kvm_vgic_load(vcpu);
590 	kvm_timer_vcpu_load(vcpu);
591 	kvm_vcpu_load_debug(vcpu);
592 	if (has_vhe())
593 		kvm_vcpu_load_vhe(vcpu);
594 	kvm_arch_vcpu_load_fp(vcpu);
595 	kvm_vcpu_pmu_restore_guest(vcpu);
596 	if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
597 		kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
598 
599 	if (kvm_vcpu_should_clear_twe(vcpu))
600 		vcpu->arch.hcr_el2 &= ~HCR_TWE;
601 	else
602 		vcpu->arch.hcr_el2 |= HCR_TWE;
603 
604 	if (kvm_vcpu_should_clear_twi(vcpu))
605 		vcpu->arch.hcr_el2 &= ~HCR_TWI;
606 	else
607 		vcpu->arch.hcr_el2 |= HCR_TWI;
608 
609 	vcpu_set_pauth_traps(vcpu);
610 
611 	if (is_protected_kvm_enabled()) {
612 		kvm_call_hyp_nvhe(__pkvm_vcpu_load,
613 				  vcpu->kvm->arch.pkvm.handle,
614 				  vcpu->vcpu_idx, vcpu->arch.hcr_el2);
615 		kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
616 			     &vcpu->arch.vgic_cpu.vgic_v3);
617 	}
618 
619 	if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
620 		vcpu_set_on_unsupported_cpu(vcpu);
621 }
622 
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)623 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
624 {
625 	if (is_protected_kvm_enabled()) {
626 		kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
627 			     &vcpu->arch.vgic_cpu.vgic_v3);
628 		kvm_call_hyp_nvhe(__pkvm_vcpu_put);
629 	}
630 
631 	kvm_vcpu_put_debug(vcpu);
632 	kvm_arch_vcpu_put_fp(vcpu);
633 	if (has_vhe())
634 		kvm_vcpu_put_vhe(vcpu);
635 	kvm_timer_vcpu_put(vcpu);
636 	kvm_vgic_put(vcpu);
637 	kvm_vcpu_pmu_restore_host(vcpu);
638 	if (vcpu_has_nv(vcpu))
639 		kvm_vcpu_put_hw_mmu(vcpu);
640 	kvm_arm_vmid_clear_active();
641 
642 	vcpu_clear_on_unsupported_cpu(vcpu);
643 	vcpu->cpu = -1;
644 }
645 
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)646 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
647 {
648 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
649 	kvm_make_request(KVM_REQ_SLEEP, vcpu);
650 	kvm_vcpu_kick(vcpu);
651 }
652 
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)653 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
654 {
655 	spin_lock(&vcpu->arch.mp_state_lock);
656 	__kvm_arm_vcpu_power_off(vcpu);
657 	spin_unlock(&vcpu->arch.mp_state_lock);
658 }
659 
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)660 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
661 {
662 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
663 }
664 
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)665 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
666 {
667 	WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
668 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
669 	kvm_vcpu_kick(vcpu);
670 }
671 
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)672 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
673 {
674 	return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
675 }
676 
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)677 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
678 				    struct kvm_mp_state *mp_state)
679 {
680 	*mp_state = READ_ONCE(vcpu->arch.mp_state);
681 
682 	return 0;
683 }
684 
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)685 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
686 				    struct kvm_mp_state *mp_state)
687 {
688 	int ret = 0;
689 
690 	spin_lock(&vcpu->arch.mp_state_lock);
691 
692 	switch (mp_state->mp_state) {
693 	case KVM_MP_STATE_RUNNABLE:
694 		WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
695 		break;
696 	case KVM_MP_STATE_STOPPED:
697 		__kvm_arm_vcpu_power_off(vcpu);
698 		break;
699 	case KVM_MP_STATE_SUSPENDED:
700 		kvm_arm_vcpu_suspend(vcpu);
701 		break;
702 	default:
703 		ret = -EINVAL;
704 	}
705 
706 	spin_unlock(&vcpu->arch.mp_state_lock);
707 
708 	return ret;
709 }
710 
711 /**
712  * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
713  * @v:		The VCPU pointer
714  *
715  * If the guest CPU is not waiting for interrupts or an interrupt line is
716  * asserted, the CPU is by definition runnable.
717  */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)718 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
719 {
720 	bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF);
721 	return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
722 		&& !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
723 }
724 
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)725 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
726 {
727 	return vcpu_mode_priv(vcpu);
728 }
729 
730 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)731 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
732 {
733 	return *vcpu_pc(vcpu);
734 }
735 #endif
736 
kvm_init_mpidr_data(struct kvm * kvm)737 static void kvm_init_mpidr_data(struct kvm *kvm)
738 {
739 	struct kvm_mpidr_data *data = NULL;
740 	unsigned long c, mask, nr_entries;
741 	u64 aff_set = 0, aff_clr = ~0UL;
742 	struct kvm_vcpu *vcpu;
743 
744 	mutex_lock(&kvm->arch.config_lock);
745 
746 	if (rcu_access_pointer(kvm->arch.mpidr_data) ||
747 	    atomic_read(&kvm->online_vcpus) == 1)
748 		goto out;
749 
750 	kvm_for_each_vcpu(c, vcpu, kvm) {
751 		u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
752 		aff_set |= aff;
753 		aff_clr &= aff;
754 	}
755 
756 	/*
757 	 * A significant bit can be either 0 or 1, and will only appear in
758 	 * aff_set. Use aff_clr to weed out the useless stuff.
759 	 */
760 	mask = aff_set ^ aff_clr;
761 	nr_entries = BIT_ULL(hweight_long(mask));
762 
763 	/*
764 	 * Don't let userspace fool us. If we need more than a single page
765 	 * to describe the compressed MPIDR array, just fall back to the
766 	 * iterative method. Single vcpu VMs do not need this either.
767 	 */
768 	if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE)
769 		data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries),
770 			       GFP_KERNEL_ACCOUNT);
771 
772 	if (!data)
773 		goto out;
774 
775 	data->mpidr_mask = mask;
776 
777 	kvm_for_each_vcpu(c, vcpu, kvm) {
778 		u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
779 		u16 index = kvm_mpidr_index(data, aff);
780 
781 		data->cmpidr_to_idx[index] = c;
782 	}
783 
784 	rcu_assign_pointer(kvm->arch.mpidr_data, data);
785 out:
786 	mutex_unlock(&kvm->arch.config_lock);
787 }
788 
789 /*
790  * Handle both the initialisation that is being done when the vcpu is
791  * run for the first time, as well as the updates that must be
792  * performed each time we get a new thread dealing with this vcpu.
793  */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)794 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
795 {
796 	struct kvm *kvm = vcpu->kvm;
797 	int ret;
798 
799 	if (!kvm_vcpu_initialized(vcpu))
800 		return -ENOEXEC;
801 
802 	if (!kvm_arm_vcpu_is_finalized(vcpu))
803 		return -EPERM;
804 
805 	ret = kvm_arch_vcpu_run_map_fp(vcpu);
806 	if (ret)
807 		return ret;
808 
809 	if (likely(vcpu_has_run_once(vcpu)))
810 		return 0;
811 
812 	kvm_init_mpidr_data(kvm);
813 
814 	if (likely(irqchip_in_kernel(kvm))) {
815 		/*
816 		 * Map the VGIC hardware resources before running a vcpu the
817 		 * first time on this VM.
818 		 */
819 		ret = kvm_vgic_map_resources(kvm);
820 		if (ret)
821 			return ret;
822 	}
823 
824 	ret = kvm_finalize_sys_regs(vcpu);
825 	if (ret)
826 		return ret;
827 
828 	/*
829 	 * This needs to happen after any restriction has been applied
830 	 * to the feature set.
831 	 */
832 	kvm_calculate_traps(vcpu);
833 
834 	ret = kvm_timer_enable(vcpu);
835 	if (ret)
836 		return ret;
837 
838 	ret = kvm_arm_pmu_v3_enable(vcpu);
839 	if (ret)
840 		return ret;
841 
842 	if (is_protected_kvm_enabled()) {
843 		ret = pkvm_create_hyp_vm(kvm);
844 		if (ret)
845 			return ret;
846 	}
847 
848 	mutex_lock(&kvm->arch.config_lock);
849 	set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
850 	mutex_unlock(&kvm->arch.config_lock);
851 
852 	return ret;
853 }
854 
kvm_arch_intc_initialized(struct kvm * kvm)855 bool kvm_arch_intc_initialized(struct kvm *kvm)
856 {
857 	return vgic_initialized(kvm);
858 }
859 
kvm_arm_halt_guest(struct kvm * kvm)860 void kvm_arm_halt_guest(struct kvm *kvm)
861 {
862 	unsigned long i;
863 	struct kvm_vcpu *vcpu;
864 
865 	kvm_for_each_vcpu(i, vcpu, kvm)
866 		vcpu->arch.pause = true;
867 	kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
868 }
869 
kvm_arm_resume_guest(struct kvm * kvm)870 void kvm_arm_resume_guest(struct kvm *kvm)
871 {
872 	unsigned long i;
873 	struct kvm_vcpu *vcpu;
874 
875 	kvm_for_each_vcpu(i, vcpu, kvm) {
876 		vcpu->arch.pause = false;
877 		__kvm_vcpu_wake_up(vcpu);
878 	}
879 }
880 
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)881 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
882 {
883 	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
884 
885 	rcuwait_wait_event(wait,
886 			   (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
887 			   TASK_INTERRUPTIBLE);
888 
889 	if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
890 		/* Awaken to handle a signal, request we sleep again later. */
891 		kvm_make_request(KVM_REQ_SLEEP, vcpu);
892 	}
893 
894 	/*
895 	 * Make sure we will observe a potential reset request if we've
896 	 * observed a change to the power state. Pairs with the smp_wmb() in
897 	 * kvm_psci_vcpu_on().
898 	 */
899 	smp_rmb();
900 }
901 
902 /**
903  * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
904  * @vcpu:	The VCPU pointer
905  *
906  * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
907  * the vCPU is runnable.  The vCPU may or may not be scheduled out, depending
908  * on when a wake event arrives, e.g. there may already be a pending wake event.
909  */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)910 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
911 {
912 	/*
913 	 * Sync back the state of the GIC CPU interface so that we have
914 	 * the latest PMR and group enables. This ensures that
915 	 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
916 	 * we have pending interrupts, e.g. when determining if the
917 	 * vCPU should block.
918 	 *
919 	 * For the same reason, we want to tell GICv4 that we need
920 	 * doorbells to be signalled, should an interrupt become pending.
921 	 */
922 	preempt_disable();
923 	vcpu_set_flag(vcpu, IN_WFI);
924 	kvm_vgic_put(vcpu);
925 	preempt_enable();
926 
927 	kvm_vcpu_halt(vcpu);
928 	vcpu_clear_flag(vcpu, IN_WFIT);
929 
930 	preempt_disable();
931 	vcpu_clear_flag(vcpu, IN_WFI);
932 	kvm_vgic_load(vcpu);
933 	preempt_enable();
934 }
935 
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)936 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
937 {
938 	if (!kvm_arm_vcpu_suspended(vcpu))
939 		return 1;
940 
941 	kvm_vcpu_wfi(vcpu);
942 
943 	/*
944 	 * The suspend state is sticky; we do not leave it until userspace
945 	 * explicitly marks the vCPU as runnable. Request that we suspend again
946 	 * later.
947 	 */
948 	kvm_make_request(KVM_REQ_SUSPEND, vcpu);
949 
950 	/*
951 	 * Check to make sure the vCPU is actually runnable. If so, exit to
952 	 * userspace informing it of the wakeup condition.
953 	 */
954 	if (kvm_arch_vcpu_runnable(vcpu)) {
955 		memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
956 		vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
957 		vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
958 		return 0;
959 	}
960 
961 	/*
962 	 * Otherwise, we were unblocked to process a different event, such as a
963 	 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
964 	 * process the event.
965 	 */
966 	return 1;
967 }
968 
969 /**
970  * check_vcpu_requests - check and handle pending vCPU requests
971  * @vcpu:	the VCPU pointer
972  *
973  * Return: 1 if we should enter the guest
974  *	   0 if we should exit to userspace
975  *	   < 0 if we should exit to userspace, where the return value indicates
976  *	   an error
977  */
check_vcpu_requests(struct kvm_vcpu * vcpu)978 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
979 {
980 	if (kvm_request_pending(vcpu)) {
981 		if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu))
982 			return -EIO;
983 
984 		if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
985 			kvm_vcpu_sleep(vcpu);
986 
987 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
988 			kvm_reset_vcpu(vcpu);
989 
990 		/*
991 		 * Clear IRQ_PENDING requests that were made to guarantee
992 		 * that a VCPU sees new virtual interrupts.
993 		 */
994 		kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
995 
996 		if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
997 			kvm_update_stolen_time(vcpu);
998 
999 		if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
1000 			/* The distributor enable bits were changed */
1001 			preempt_disable();
1002 			vgic_v4_put(vcpu);
1003 			vgic_v4_load(vcpu);
1004 			preempt_enable();
1005 		}
1006 
1007 		if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
1008 			kvm_vcpu_reload_pmu(vcpu);
1009 
1010 		if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
1011 			kvm_vcpu_pmu_restore_guest(vcpu);
1012 
1013 		if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
1014 			return kvm_vcpu_suspend(vcpu);
1015 
1016 		if (kvm_dirty_ring_check_request(vcpu))
1017 			return 0;
1018 
1019 		check_nested_vcpu_requests(vcpu);
1020 	}
1021 
1022 	return 1;
1023 }
1024 
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)1025 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
1026 {
1027 	if (likely(!vcpu_mode_is_32bit(vcpu)))
1028 		return false;
1029 
1030 	if (vcpu_has_nv(vcpu))
1031 		return true;
1032 
1033 	return !kvm_supports_32bit_el0();
1034 }
1035 
1036 /**
1037  * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
1038  * @vcpu:	The VCPU pointer
1039  * @ret:	Pointer to write optional return code
1040  *
1041  * Returns: true if the VCPU needs to return to a preemptible + interruptible
1042  *	    and skip guest entry.
1043  *
1044  * This function disambiguates between two different types of exits: exits to a
1045  * preemptible + interruptible kernel context and exits to userspace. For an
1046  * exit to userspace, this function will write the return code to ret and return
1047  * true. For an exit to preemptible + interruptible kernel context (i.e. check
1048  * for pending work and re-enter), return true without writing to ret.
1049  */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)1050 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
1051 {
1052 	struct kvm_run *run = vcpu->run;
1053 
1054 	/*
1055 	 * If we're using a userspace irqchip, then check if we need
1056 	 * to tell a userspace irqchip about timer or PMU level
1057 	 * changes and if so, exit to userspace (the actual level
1058 	 * state gets updated in kvm_timer_update_run and
1059 	 * kvm_pmu_update_run below).
1060 	 */
1061 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1062 		if (kvm_timer_should_notify_user(vcpu) ||
1063 		    kvm_pmu_should_notify_user(vcpu)) {
1064 			*ret = -EINTR;
1065 			run->exit_reason = KVM_EXIT_INTR;
1066 			return true;
1067 		}
1068 	}
1069 
1070 	if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
1071 		run->exit_reason = KVM_EXIT_FAIL_ENTRY;
1072 		run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
1073 		run->fail_entry.cpu = smp_processor_id();
1074 		*ret = 0;
1075 		return true;
1076 	}
1077 
1078 	return kvm_request_pending(vcpu) ||
1079 			xfer_to_guest_mode_work_pending();
1080 }
1081 
1082 /*
1083  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
1084  * the vCPU is running.
1085  *
1086  * This must be noinstr as instrumentation may make use of RCU, and this is not
1087  * safe during the EQS.
1088  */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1089 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1090 {
1091 	int ret;
1092 
1093 	guest_state_enter_irqoff();
1094 	ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1095 	guest_state_exit_irqoff();
1096 
1097 	return ret;
1098 }
1099 
1100 /**
1101  * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1102  * @vcpu:	The VCPU pointer
1103  *
1104  * This function is called through the VCPU_RUN ioctl called from user space. It
1105  * will execute VM code in a loop until the time slice for the process is used
1106  * or some emulation is needed from user space in which case the function will
1107  * return with return value 0 and with the kvm_run structure filled in with the
1108  * required data for the requested emulation.
1109  */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1110 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1111 {
1112 	struct kvm_run *run = vcpu->run;
1113 	int ret;
1114 
1115 	if (run->exit_reason == KVM_EXIT_MMIO) {
1116 		ret = kvm_handle_mmio_return(vcpu);
1117 		if (ret <= 0)
1118 			return ret;
1119 	}
1120 
1121 	vcpu_load(vcpu);
1122 
1123 	if (!vcpu->wants_to_run) {
1124 		ret = -EINTR;
1125 		goto out;
1126 	}
1127 
1128 	kvm_sigset_activate(vcpu);
1129 
1130 	ret = 1;
1131 	run->exit_reason = KVM_EXIT_UNKNOWN;
1132 	run->flags = 0;
1133 	while (ret > 0) {
1134 		/*
1135 		 * Check conditions before entering the guest
1136 		 */
1137 		ret = xfer_to_guest_mode_handle_work(vcpu);
1138 		if (!ret)
1139 			ret = 1;
1140 
1141 		if (ret > 0)
1142 			ret = check_vcpu_requests(vcpu);
1143 
1144 		/*
1145 		 * Preparing the interrupts to be injected also
1146 		 * involves poking the GIC, which must be done in a
1147 		 * non-preemptible context.
1148 		 */
1149 		preempt_disable();
1150 
1151 		kvm_pmu_flush_hwstate(vcpu);
1152 
1153 		local_irq_disable();
1154 
1155 		kvm_vgic_flush_hwstate(vcpu);
1156 
1157 		kvm_pmu_update_vcpu_events(vcpu);
1158 
1159 		/*
1160 		 * Ensure we set mode to IN_GUEST_MODE after we disable
1161 		 * interrupts and before the final VCPU requests check.
1162 		 * See the comment in kvm_vcpu_exiting_guest_mode() and
1163 		 * Documentation/virt/kvm/vcpu-requests.rst
1164 		 */
1165 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1166 
1167 		if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1168 			vcpu->mode = OUTSIDE_GUEST_MODE;
1169 			isb(); /* Ensure work in x_flush_hwstate is committed */
1170 			kvm_pmu_sync_hwstate(vcpu);
1171 			if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1172 				kvm_timer_sync_user(vcpu);
1173 			kvm_vgic_sync_hwstate(vcpu);
1174 			local_irq_enable();
1175 			preempt_enable();
1176 			continue;
1177 		}
1178 
1179 		kvm_arch_vcpu_ctxflush_fp(vcpu);
1180 
1181 		/**************************************************************
1182 		 * Enter the guest
1183 		 */
1184 		trace_kvm_entry(*vcpu_pc(vcpu));
1185 		guest_timing_enter_irqoff();
1186 
1187 		ret = kvm_arm_vcpu_enter_exit(vcpu);
1188 
1189 		vcpu->mode = OUTSIDE_GUEST_MODE;
1190 		vcpu->stat.exits++;
1191 		/*
1192 		 * Back from guest
1193 		 *************************************************************/
1194 
1195 		/*
1196 		 * We must sync the PMU state before the vgic state so
1197 		 * that the vgic can properly sample the updated state of the
1198 		 * interrupt line.
1199 		 */
1200 		kvm_pmu_sync_hwstate(vcpu);
1201 
1202 		/*
1203 		 * Sync the vgic state before syncing the timer state because
1204 		 * the timer code needs to know if the virtual timer
1205 		 * interrupts are active.
1206 		 */
1207 		kvm_vgic_sync_hwstate(vcpu);
1208 
1209 		/*
1210 		 * Sync the timer hardware state before enabling interrupts as
1211 		 * we don't want vtimer interrupts to race with syncing the
1212 		 * timer virtual interrupt state.
1213 		 */
1214 		if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1215 			kvm_timer_sync_user(vcpu);
1216 
1217 		if (is_hyp_ctxt(vcpu))
1218 			kvm_timer_sync_nested(vcpu);
1219 
1220 		kvm_arch_vcpu_ctxsync_fp(vcpu);
1221 
1222 		/*
1223 		 * We must ensure that any pending interrupts are taken before
1224 		 * we exit guest timing so that timer ticks are accounted as
1225 		 * guest time. Transiently unmask interrupts so that any
1226 		 * pending interrupts are taken.
1227 		 *
1228 		 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1229 		 * context synchronization event) is necessary to ensure that
1230 		 * pending interrupts are taken.
1231 		 */
1232 		if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1233 			local_irq_enable();
1234 			isb();
1235 			local_irq_disable();
1236 		}
1237 
1238 		guest_timing_exit_irqoff();
1239 
1240 		local_irq_enable();
1241 
1242 		trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1243 
1244 		/* Exit types that need handling before we can be preempted */
1245 		handle_exit_early(vcpu, ret);
1246 
1247 		preempt_enable();
1248 
1249 		/*
1250 		 * The ARMv8 architecture doesn't give the hypervisor
1251 		 * a mechanism to prevent a guest from dropping to AArch32 EL0
1252 		 * if implemented by the CPU. If we spot the guest in such
1253 		 * state and that we decided it wasn't supposed to do so (like
1254 		 * with the asymmetric AArch32 case), return to userspace with
1255 		 * a fatal error.
1256 		 */
1257 		if (vcpu_mode_is_bad_32bit(vcpu)) {
1258 			/*
1259 			 * As we have caught the guest red-handed, decide that
1260 			 * it isn't fit for purpose anymore by making the vcpu
1261 			 * invalid. The VMM can try and fix it by issuing  a
1262 			 * KVM_ARM_VCPU_INIT if it really wants to.
1263 			 */
1264 			vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1265 			ret = ARM_EXCEPTION_IL;
1266 		}
1267 
1268 		ret = handle_exit(vcpu, ret);
1269 	}
1270 
1271 	/* Tell userspace about in-kernel device output levels */
1272 	if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1273 		kvm_timer_update_run(vcpu);
1274 		kvm_pmu_update_run(vcpu);
1275 	}
1276 
1277 	kvm_sigset_deactivate(vcpu);
1278 
1279 out:
1280 	/*
1281 	 * In the unlikely event that we are returning to userspace
1282 	 * with pending exceptions or PC adjustment, commit these
1283 	 * adjustments in order to give userspace a consistent view of
1284 	 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1285 	 * being preempt-safe on VHE.
1286 	 */
1287 	if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1288 		     vcpu_get_flag(vcpu, INCREMENT_PC)))
1289 		kvm_call_hyp(__kvm_adjust_pc, vcpu);
1290 
1291 	vcpu_put(vcpu);
1292 	return ret;
1293 }
1294 
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1295 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1296 {
1297 	int bit_index;
1298 	bool set;
1299 	unsigned long *hcr;
1300 
1301 	if (number == KVM_ARM_IRQ_CPU_IRQ)
1302 		bit_index = __ffs(HCR_VI);
1303 	else /* KVM_ARM_IRQ_CPU_FIQ */
1304 		bit_index = __ffs(HCR_VF);
1305 
1306 	hcr = vcpu_hcr(vcpu);
1307 	if (level)
1308 		set = test_and_set_bit(bit_index, hcr);
1309 	else
1310 		set = test_and_clear_bit(bit_index, hcr);
1311 
1312 	/*
1313 	 * If we didn't change anything, no need to wake up or kick other CPUs
1314 	 */
1315 	if (set == level)
1316 		return 0;
1317 
1318 	/*
1319 	 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1320 	 * trigger a world-switch round on the running physical CPU to set the
1321 	 * virtual IRQ/FIQ fields in the HCR appropriately.
1322 	 */
1323 	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1324 	kvm_vcpu_kick(vcpu);
1325 
1326 	return 0;
1327 }
1328 
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1329 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1330 			  bool line_status)
1331 {
1332 	u32 irq = irq_level->irq;
1333 	unsigned int irq_type, vcpu_id, irq_num;
1334 	struct kvm_vcpu *vcpu = NULL;
1335 	bool level = irq_level->level;
1336 
1337 	irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1338 	vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1339 	vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1340 	irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1341 
1342 	trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
1343 
1344 	switch (irq_type) {
1345 	case KVM_ARM_IRQ_TYPE_CPU:
1346 		if (irqchip_in_kernel(kvm))
1347 			return -ENXIO;
1348 
1349 		vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1350 		if (!vcpu)
1351 			return -EINVAL;
1352 
1353 		if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1354 			return -EINVAL;
1355 
1356 		return vcpu_interrupt_line(vcpu, irq_num, level);
1357 	case KVM_ARM_IRQ_TYPE_PPI:
1358 		if (!irqchip_in_kernel(kvm))
1359 			return -ENXIO;
1360 
1361 		vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1362 		if (!vcpu)
1363 			return -EINVAL;
1364 
1365 		if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1366 			return -EINVAL;
1367 
1368 		return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
1369 	case KVM_ARM_IRQ_TYPE_SPI:
1370 		if (!irqchip_in_kernel(kvm))
1371 			return -ENXIO;
1372 
1373 		if (irq_num < VGIC_NR_PRIVATE_IRQS)
1374 			return -EINVAL;
1375 
1376 		return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
1377 	}
1378 
1379 	return -EINVAL;
1380 }
1381 
system_supported_vcpu_features(void)1382 static unsigned long system_supported_vcpu_features(void)
1383 {
1384 	unsigned long features = KVM_VCPU_VALID_FEATURES;
1385 
1386 	if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1))
1387 		clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features);
1388 
1389 	if (!kvm_arm_support_pmu_v3())
1390 		clear_bit(KVM_ARM_VCPU_PMU_V3, &features);
1391 
1392 	if (!system_supports_sve())
1393 		clear_bit(KVM_ARM_VCPU_SVE, &features);
1394 
1395 	if (!kvm_has_full_ptr_auth()) {
1396 		clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features);
1397 		clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features);
1398 	}
1399 
1400 	if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT))
1401 		clear_bit(KVM_ARM_VCPU_HAS_EL2, &features);
1402 
1403 	return features;
1404 }
1405 
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1406 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1407 					const struct kvm_vcpu_init *init)
1408 {
1409 	unsigned long features = init->features[0];
1410 	int i;
1411 
1412 	if (features & ~KVM_VCPU_VALID_FEATURES)
1413 		return -ENOENT;
1414 
1415 	for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1416 		if (init->features[i])
1417 			return -ENOENT;
1418 	}
1419 
1420 	if (features & ~system_supported_vcpu_features())
1421 		return -EINVAL;
1422 
1423 	/*
1424 	 * For now make sure that both address/generic pointer authentication
1425 	 * features are requested by the userspace together.
1426 	 */
1427 	if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) !=
1428 	    test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features))
1429 		return -EINVAL;
1430 
1431 	if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1432 		return 0;
1433 
1434 	/* MTE is incompatible with AArch32 */
1435 	if (kvm_has_mte(vcpu->kvm))
1436 		return -EINVAL;
1437 
1438 	/* NV is incompatible with AArch32 */
1439 	if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1440 		return -EINVAL;
1441 
1442 	return 0;
1443 }
1444 
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1445 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1446 				  const struct kvm_vcpu_init *init)
1447 {
1448 	unsigned long features = init->features[0];
1449 
1450 	return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,
1451 			     KVM_VCPU_MAX_FEATURES);
1452 }
1453 
kvm_setup_vcpu(struct kvm_vcpu * vcpu)1454 static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
1455 {
1456 	struct kvm *kvm = vcpu->kvm;
1457 	int ret = 0;
1458 
1459 	/*
1460 	 * When the vCPU has a PMU, but no PMU is set for the guest
1461 	 * yet, set the default one.
1462 	 */
1463 	if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu)
1464 		ret = kvm_arm_set_default_pmu(kvm);
1465 
1466 	/* Prepare for nested if required */
1467 	if (!ret && vcpu_has_nv(vcpu))
1468 		ret = kvm_vcpu_init_nested(vcpu);
1469 
1470 	return ret;
1471 }
1472 
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1473 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1474 				 const struct kvm_vcpu_init *init)
1475 {
1476 	unsigned long features = init->features[0];
1477 	struct kvm *kvm = vcpu->kvm;
1478 	int ret = -EINVAL;
1479 
1480 	mutex_lock(&kvm->arch.config_lock);
1481 
1482 	if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1483 	    kvm_vcpu_init_changed(vcpu, init))
1484 		goto out_unlock;
1485 
1486 	bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1487 
1488 	ret = kvm_setup_vcpu(vcpu);
1489 	if (ret)
1490 		goto out_unlock;
1491 
1492 	/* Now we know what it is, we can reset it. */
1493 	kvm_reset_vcpu(vcpu);
1494 
1495 	set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1496 	vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1497 	ret = 0;
1498 out_unlock:
1499 	mutex_unlock(&kvm->arch.config_lock);
1500 	return ret;
1501 }
1502 
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1503 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1504 			       const struct kvm_vcpu_init *init)
1505 {
1506 	int ret;
1507 
1508 	if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1509 	    init->target != kvm_target_cpu())
1510 		return -EINVAL;
1511 
1512 	ret = kvm_vcpu_init_check_features(vcpu, init);
1513 	if (ret)
1514 		return ret;
1515 
1516 	if (!kvm_vcpu_initialized(vcpu))
1517 		return __kvm_vcpu_set_target(vcpu, init);
1518 
1519 	if (kvm_vcpu_init_changed(vcpu, init))
1520 		return -EINVAL;
1521 
1522 	kvm_reset_vcpu(vcpu);
1523 	return 0;
1524 }
1525 
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1526 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1527 					 struct kvm_vcpu_init *init)
1528 {
1529 	bool power_off = false;
1530 	int ret;
1531 
1532 	/*
1533 	 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1534 	 * reflecting it in the finalized feature set, thus limiting its scope
1535 	 * to a single KVM_ARM_VCPU_INIT call.
1536 	 */
1537 	if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1538 		init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1539 		power_off = true;
1540 	}
1541 
1542 	ret = kvm_vcpu_set_target(vcpu, init);
1543 	if (ret)
1544 		return ret;
1545 
1546 	/*
1547 	 * Ensure a rebooted VM will fault in RAM pages and detect if the
1548 	 * guest MMU is turned off and flush the caches as needed.
1549 	 *
1550 	 * S2FWB enforces all memory accesses to RAM being cacheable,
1551 	 * ensuring that the data side is always coherent. We still
1552 	 * need to invalidate the I-cache though, as FWB does *not*
1553 	 * imply CTR_EL0.DIC.
1554 	 */
1555 	if (vcpu_has_run_once(vcpu)) {
1556 		if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1557 			stage2_unmap_vm(vcpu->kvm);
1558 		else
1559 			icache_inval_all_pou();
1560 	}
1561 
1562 	vcpu_reset_hcr(vcpu);
1563 
1564 	/*
1565 	 * Handle the "start in power-off" case.
1566 	 */
1567 	spin_lock(&vcpu->arch.mp_state_lock);
1568 
1569 	if (power_off)
1570 		__kvm_arm_vcpu_power_off(vcpu);
1571 	else
1572 		WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1573 
1574 	spin_unlock(&vcpu->arch.mp_state_lock);
1575 
1576 	return 0;
1577 }
1578 
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1579 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1580 				 struct kvm_device_attr *attr)
1581 {
1582 	int ret = -ENXIO;
1583 
1584 	switch (attr->group) {
1585 	default:
1586 		ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1587 		break;
1588 	}
1589 
1590 	return ret;
1591 }
1592 
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1593 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1594 				 struct kvm_device_attr *attr)
1595 {
1596 	int ret = -ENXIO;
1597 
1598 	switch (attr->group) {
1599 	default:
1600 		ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1601 		break;
1602 	}
1603 
1604 	return ret;
1605 }
1606 
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1607 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1608 				 struct kvm_device_attr *attr)
1609 {
1610 	int ret = -ENXIO;
1611 
1612 	switch (attr->group) {
1613 	default:
1614 		ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1615 		break;
1616 	}
1617 
1618 	return ret;
1619 }
1620 
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1621 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1622 				   struct kvm_vcpu_events *events)
1623 {
1624 	memset(events, 0, sizeof(*events));
1625 
1626 	return __kvm_arm_vcpu_get_events(vcpu, events);
1627 }
1628 
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1629 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1630 				   struct kvm_vcpu_events *events)
1631 {
1632 	int i;
1633 
1634 	/* check whether the reserved field is zero */
1635 	for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1636 		if (events->reserved[i])
1637 			return -EINVAL;
1638 
1639 	/* check whether the pad field is zero */
1640 	for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1641 		if (events->exception.pad[i])
1642 			return -EINVAL;
1643 
1644 	return __kvm_arm_vcpu_set_events(vcpu, events);
1645 }
1646 
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1647 long kvm_arch_vcpu_ioctl(struct file *filp,
1648 			 unsigned int ioctl, unsigned long arg)
1649 {
1650 	struct kvm_vcpu *vcpu = filp->private_data;
1651 	void __user *argp = (void __user *)arg;
1652 	struct kvm_device_attr attr;
1653 	long r;
1654 
1655 	switch (ioctl) {
1656 	case KVM_ARM_VCPU_INIT: {
1657 		struct kvm_vcpu_init init;
1658 
1659 		r = -EFAULT;
1660 		if (copy_from_user(&init, argp, sizeof(init)))
1661 			break;
1662 
1663 		r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1664 		break;
1665 	}
1666 	case KVM_SET_ONE_REG:
1667 	case KVM_GET_ONE_REG: {
1668 		struct kvm_one_reg reg;
1669 
1670 		r = -ENOEXEC;
1671 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1672 			break;
1673 
1674 		r = -EFAULT;
1675 		if (copy_from_user(&reg, argp, sizeof(reg)))
1676 			break;
1677 
1678 		/*
1679 		 * We could owe a reset due to PSCI. Handle the pending reset
1680 		 * here to ensure userspace register accesses are ordered after
1681 		 * the reset.
1682 		 */
1683 		if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1684 			kvm_reset_vcpu(vcpu);
1685 
1686 		if (ioctl == KVM_SET_ONE_REG)
1687 			r = kvm_arm_set_reg(vcpu, &reg);
1688 		else
1689 			r = kvm_arm_get_reg(vcpu, &reg);
1690 		break;
1691 	}
1692 	case KVM_GET_REG_LIST: {
1693 		struct kvm_reg_list __user *user_list = argp;
1694 		struct kvm_reg_list reg_list;
1695 		unsigned n;
1696 
1697 		r = -ENOEXEC;
1698 		if (unlikely(!kvm_vcpu_initialized(vcpu)))
1699 			break;
1700 
1701 		r = -EPERM;
1702 		if (!kvm_arm_vcpu_is_finalized(vcpu))
1703 			break;
1704 
1705 		r = -EFAULT;
1706 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1707 			break;
1708 		n = reg_list.n;
1709 		reg_list.n = kvm_arm_num_regs(vcpu);
1710 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1711 			break;
1712 		r = -E2BIG;
1713 		if (n < reg_list.n)
1714 			break;
1715 		r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1716 		break;
1717 	}
1718 	case KVM_SET_DEVICE_ATTR: {
1719 		r = -EFAULT;
1720 		if (copy_from_user(&attr, argp, sizeof(attr)))
1721 			break;
1722 		r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1723 		break;
1724 	}
1725 	case KVM_GET_DEVICE_ATTR: {
1726 		r = -EFAULT;
1727 		if (copy_from_user(&attr, argp, sizeof(attr)))
1728 			break;
1729 		r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1730 		break;
1731 	}
1732 	case KVM_HAS_DEVICE_ATTR: {
1733 		r = -EFAULT;
1734 		if (copy_from_user(&attr, argp, sizeof(attr)))
1735 			break;
1736 		r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1737 		break;
1738 	}
1739 	case KVM_GET_VCPU_EVENTS: {
1740 		struct kvm_vcpu_events events;
1741 
1742 		if (kvm_arm_vcpu_get_events(vcpu, &events))
1743 			return -EINVAL;
1744 
1745 		if (copy_to_user(argp, &events, sizeof(events)))
1746 			return -EFAULT;
1747 
1748 		return 0;
1749 	}
1750 	case KVM_SET_VCPU_EVENTS: {
1751 		struct kvm_vcpu_events events;
1752 
1753 		if (copy_from_user(&events, argp, sizeof(events)))
1754 			return -EFAULT;
1755 
1756 		return kvm_arm_vcpu_set_events(vcpu, &events);
1757 	}
1758 	case KVM_ARM_VCPU_FINALIZE: {
1759 		int what;
1760 
1761 		if (!kvm_vcpu_initialized(vcpu))
1762 			return -ENOEXEC;
1763 
1764 		if (get_user(what, (const int __user *)argp))
1765 			return -EFAULT;
1766 
1767 		return kvm_arm_vcpu_finalize(vcpu, what);
1768 	}
1769 	default:
1770 		r = -EINVAL;
1771 	}
1772 
1773 	return r;
1774 }
1775 
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1776 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1777 {
1778 
1779 }
1780 
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1781 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1782 					struct kvm_arm_device_addr *dev_addr)
1783 {
1784 	switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1785 	case KVM_ARM_DEVICE_VGIC_V2:
1786 		if (!vgic_present)
1787 			return -ENXIO;
1788 		return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1789 	default:
1790 		return -ENODEV;
1791 	}
1792 }
1793 
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1794 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1795 {
1796 	switch (attr->group) {
1797 	case KVM_ARM_VM_SMCCC_CTRL:
1798 		return kvm_vm_smccc_has_attr(kvm, attr);
1799 	default:
1800 		return -ENXIO;
1801 	}
1802 }
1803 
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1804 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1805 {
1806 	switch (attr->group) {
1807 	case KVM_ARM_VM_SMCCC_CTRL:
1808 		return kvm_vm_smccc_set_attr(kvm, attr);
1809 	default:
1810 		return -ENXIO;
1811 	}
1812 }
1813 
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1814 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1815 {
1816 	struct kvm *kvm = filp->private_data;
1817 	void __user *argp = (void __user *)arg;
1818 	struct kvm_device_attr attr;
1819 
1820 	switch (ioctl) {
1821 	case KVM_CREATE_IRQCHIP: {
1822 		int ret;
1823 		if (!vgic_present)
1824 			return -ENXIO;
1825 		mutex_lock(&kvm->lock);
1826 		ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1827 		mutex_unlock(&kvm->lock);
1828 		return ret;
1829 	}
1830 	case KVM_ARM_SET_DEVICE_ADDR: {
1831 		struct kvm_arm_device_addr dev_addr;
1832 
1833 		if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1834 			return -EFAULT;
1835 		return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1836 	}
1837 	case KVM_ARM_PREFERRED_TARGET: {
1838 		struct kvm_vcpu_init init = {
1839 			.target = KVM_ARM_TARGET_GENERIC_V8,
1840 		};
1841 
1842 		if (copy_to_user(argp, &init, sizeof(init)))
1843 			return -EFAULT;
1844 
1845 		return 0;
1846 	}
1847 	case KVM_ARM_MTE_COPY_TAGS: {
1848 		struct kvm_arm_copy_mte_tags copy_tags;
1849 
1850 		if (copy_from_user(&copy_tags, argp, sizeof(copy_tags)))
1851 			return -EFAULT;
1852 		return kvm_vm_ioctl_mte_copy_tags(kvm, &copy_tags);
1853 	}
1854 	case KVM_ARM_SET_COUNTER_OFFSET: {
1855 		struct kvm_arm_counter_offset offset;
1856 
1857 		if (copy_from_user(&offset, argp, sizeof(offset)))
1858 			return -EFAULT;
1859 		return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1860 	}
1861 	case KVM_HAS_DEVICE_ATTR: {
1862 		if (copy_from_user(&attr, argp, sizeof(attr)))
1863 			return -EFAULT;
1864 
1865 		return kvm_vm_has_attr(kvm, &attr);
1866 	}
1867 	case KVM_SET_DEVICE_ATTR: {
1868 		if (copy_from_user(&attr, argp, sizeof(attr)))
1869 			return -EFAULT;
1870 
1871 		return kvm_vm_set_attr(kvm, &attr);
1872 	}
1873 	case KVM_ARM_GET_REG_WRITABLE_MASKS: {
1874 		struct reg_mask_range range;
1875 
1876 		if (copy_from_user(&range, argp, sizeof(range)))
1877 			return -EFAULT;
1878 		return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range);
1879 	}
1880 	default:
1881 		return -EINVAL;
1882 	}
1883 }
1884 
1885 /* unlocks vcpus from @vcpu_lock_idx and smaller */
unlock_vcpus(struct kvm * kvm,int vcpu_lock_idx)1886 static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx)
1887 {
1888 	struct kvm_vcpu *tmp_vcpu;
1889 
1890 	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
1891 		tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
1892 		mutex_unlock(&tmp_vcpu->mutex);
1893 	}
1894 }
1895 
unlock_all_vcpus(struct kvm * kvm)1896 void unlock_all_vcpus(struct kvm *kvm)
1897 {
1898 	lockdep_assert_held(&kvm->lock);
1899 
1900 	unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1);
1901 }
1902 
1903 /* Returns true if all vcpus were locked, false otherwise */
lock_all_vcpus(struct kvm * kvm)1904 bool lock_all_vcpus(struct kvm *kvm)
1905 {
1906 	struct kvm_vcpu *tmp_vcpu;
1907 	unsigned long c;
1908 
1909 	lockdep_assert_held(&kvm->lock);
1910 
1911 	/*
1912 	 * Any time a vcpu is in an ioctl (including running), the
1913 	 * core KVM code tries to grab the vcpu->mutex.
1914 	 *
1915 	 * By grabbing the vcpu->mutex of all VCPUs we ensure that no
1916 	 * other VCPUs can fiddle with the state while we access it.
1917 	 */
1918 	kvm_for_each_vcpu(c, tmp_vcpu, kvm) {
1919 		if (!mutex_trylock(&tmp_vcpu->mutex)) {
1920 			unlock_vcpus(kvm, c - 1);
1921 			return false;
1922 		}
1923 	}
1924 
1925 	return true;
1926 }
1927 
nvhe_percpu_size(void)1928 static unsigned long nvhe_percpu_size(void)
1929 {
1930 	return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1931 		(unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1932 }
1933 
nvhe_percpu_order(void)1934 static unsigned long nvhe_percpu_order(void)
1935 {
1936 	unsigned long size = nvhe_percpu_size();
1937 
1938 	return size ? get_order(size) : 0;
1939 }
1940 
pkvm_host_sve_state_order(void)1941 static size_t pkvm_host_sve_state_order(void)
1942 {
1943 	return get_order(pkvm_host_sve_state_size());
1944 }
1945 
1946 /* A lookup table holding the hypervisor VA for each vector slot */
1947 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1948 
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1949 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1950 {
1951 	hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1952 }
1953 
kvm_init_vector_slots(void)1954 static int kvm_init_vector_slots(void)
1955 {
1956 	int err;
1957 	void *base;
1958 
1959 	base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1960 	kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1961 
1962 	base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1963 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1964 
1965 	if (kvm_system_needs_idmapped_vectors() &&
1966 	    !is_protected_kvm_enabled()) {
1967 		err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1968 					       __BP_HARDEN_HYP_VECS_SZ, &base);
1969 		if (err)
1970 			return err;
1971 	}
1972 
1973 	kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1974 	kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1975 	return 0;
1976 }
1977 
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1978 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1979 {
1980 	struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
1981 	unsigned long tcr;
1982 
1983 	/*
1984 	 * Calculate the raw per-cpu offset without a translation from the
1985 	 * kernel's mapping to the linear mapping, and store it in tpidr_el2
1986 	 * so that we can use adr_l to access per-cpu variables in EL2.
1987 	 * Also drop the KASAN tag which gets in the way...
1988 	 */
1989 	params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
1990 			    (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
1991 
1992 	params->mair_el2 = read_sysreg(mair_el1);
1993 
1994 	tcr = read_sysreg(tcr_el1);
1995 	if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
1996 		tcr &= ~(TCR_HD | TCR_HA | TCR_A1 | TCR_T0SZ_MASK);
1997 		tcr |= TCR_EPD1_MASK;
1998 	} else {
1999 		unsigned long ips = FIELD_GET(TCR_IPS_MASK, tcr);
2000 
2001 		tcr &= TCR_EL2_MASK;
2002 		tcr |= TCR_EL2_RES1 | FIELD_PREP(TCR_EL2_PS_MASK, ips);
2003 		if (lpa2_is_enabled())
2004 			tcr |= TCR_EL2_DS;
2005 	}
2006 	tcr |= TCR_T0SZ(hyp_va_bits);
2007 	params->tcr_el2 = tcr;
2008 
2009 	params->pgd_pa = kvm_mmu_get_httbr();
2010 	if (is_protected_kvm_enabled())
2011 		params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
2012 	else
2013 		params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
2014 	if (cpus_have_final_cap(ARM64_KVM_HVHE))
2015 		params->hcr_el2 |= HCR_E2H;
2016 	params->vttbr = params->vtcr = 0;
2017 
2018 	/*
2019 	 * Flush the init params from the data cache because the struct will
2020 	 * be read while the MMU is off.
2021 	 */
2022 	kvm_flush_dcache_to_poc(params, sizeof(*params));
2023 }
2024 
hyp_install_host_vector(void)2025 static void hyp_install_host_vector(void)
2026 {
2027 	struct kvm_nvhe_init_params *params;
2028 	struct arm_smccc_res res;
2029 
2030 	/* Switch from the HYP stub to our own HYP init vector */
2031 	__hyp_set_vectors(kvm_get_idmap_vector());
2032 
2033 	/*
2034 	 * Call initialization code, and switch to the full blown HYP code.
2035 	 * If the cpucaps haven't been finalized yet, something has gone very
2036 	 * wrong, and hyp will crash and burn when it uses any
2037 	 * cpus_have_*_cap() wrapper.
2038 	 */
2039 	BUG_ON(!system_capabilities_finalized());
2040 	params = this_cpu_ptr_nvhe_sym(kvm_init_params);
2041 	arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
2042 	WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
2043 }
2044 
cpu_init_hyp_mode(void)2045 static void cpu_init_hyp_mode(void)
2046 {
2047 	hyp_install_host_vector();
2048 
2049 	/*
2050 	 * Disabling SSBD on a non-VHE system requires us to enable SSBS
2051 	 * at EL2.
2052 	 */
2053 	if (this_cpu_has_cap(ARM64_SSBS) &&
2054 	    arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
2055 		kvm_call_hyp_nvhe(__kvm_enable_ssbs);
2056 	}
2057 }
2058 
cpu_hyp_reset(void)2059 static void cpu_hyp_reset(void)
2060 {
2061 	if (!is_kernel_in_hyp_mode())
2062 		__hyp_reset_vectors();
2063 }
2064 
2065 /*
2066  * EL2 vectors can be mapped and rerouted in a number of ways,
2067  * depending on the kernel configuration and CPU present:
2068  *
2069  * - If the CPU is affected by Spectre-v2, the hardening sequence is
2070  *   placed in one of the vector slots, which is executed before jumping
2071  *   to the real vectors.
2072  *
2073  * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
2074  *   containing the hardening sequence is mapped next to the idmap page,
2075  *   and executed before jumping to the real vectors.
2076  *
2077  * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
2078  *   empty slot is selected, mapped next to the idmap page, and
2079  *   executed before jumping to the real vectors.
2080  *
2081  * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
2082  * VHE, as we don't have hypervisor-specific mappings. If the system
2083  * is VHE and yet selects this capability, it will be ignored.
2084  */
cpu_set_hyp_vector(void)2085 static void cpu_set_hyp_vector(void)
2086 {
2087 	struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
2088 	void *vector = hyp_spectre_vector_selector[data->slot];
2089 
2090 	if (!is_protected_kvm_enabled())
2091 		*this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
2092 	else
2093 		kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
2094 }
2095 
cpu_hyp_init_context(void)2096 static void cpu_hyp_init_context(void)
2097 {
2098 	kvm_init_host_cpu_context(host_data_ptr(host_ctxt));
2099 	kvm_init_host_debug_data();
2100 
2101 	if (!is_kernel_in_hyp_mode())
2102 		cpu_init_hyp_mode();
2103 }
2104 
cpu_hyp_init_features(void)2105 static void cpu_hyp_init_features(void)
2106 {
2107 	cpu_set_hyp_vector();
2108 
2109 	if (is_kernel_in_hyp_mode())
2110 		kvm_timer_init_vhe();
2111 
2112 	if (vgic_present)
2113 		kvm_vgic_init_cpu_hardware();
2114 }
2115 
cpu_hyp_reinit(void)2116 static void cpu_hyp_reinit(void)
2117 {
2118 	cpu_hyp_reset();
2119 	cpu_hyp_init_context();
2120 	cpu_hyp_init_features();
2121 }
2122 
cpu_hyp_init(void * discard)2123 static void cpu_hyp_init(void *discard)
2124 {
2125 	if (!__this_cpu_read(kvm_hyp_initialized)) {
2126 		cpu_hyp_reinit();
2127 		__this_cpu_write(kvm_hyp_initialized, 1);
2128 	}
2129 }
2130 
cpu_hyp_uninit(void * discard)2131 static void cpu_hyp_uninit(void *discard)
2132 {
2133 	if (__this_cpu_read(kvm_hyp_initialized)) {
2134 		cpu_hyp_reset();
2135 		__this_cpu_write(kvm_hyp_initialized, 0);
2136 	}
2137 }
2138 
kvm_arch_enable_virtualization_cpu(void)2139 int kvm_arch_enable_virtualization_cpu(void)
2140 {
2141 	/*
2142 	 * Most calls to this function are made with migration
2143 	 * disabled, but not with preemption disabled. The former is
2144 	 * enough to ensure correctness, but most of the helpers
2145 	 * expect the later and will throw a tantrum otherwise.
2146 	 */
2147 	preempt_disable();
2148 
2149 	cpu_hyp_init(NULL);
2150 
2151 	kvm_vgic_cpu_up();
2152 	kvm_timer_cpu_up();
2153 
2154 	preempt_enable();
2155 
2156 	return 0;
2157 }
2158 
kvm_arch_disable_virtualization_cpu(void)2159 void kvm_arch_disable_virtualization_cpu(void)
2160 {
2161 	kvm_timer_cpu_down();
2162 	kvm_vgic_cpu_down();
2163 
2164 	if (!is_protected_kvm_enabled())
2165 		cpu_hyp_uninit(NULL);
2166 }
2167 
2168 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2169 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2170 				    unsigned long cmd,
2171 				    void *v)
2172 {
2173 	/*
2174 	 * kvm_hyp_initialized is left with its old value over
2175 	 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2176 	 * re-enable hyp.
2177 	 */
2178 	switch (cmd) {
2179 	case CPU_PM_ENTER:
2180 		if (__this_cpu_read(kvm_hyp_initialized))
2181 			/*
2182 			 * don't update kvm_hyp_initialized here
2183 			 * so that the hyp will be re-enabled
2184 			 * when we resume. See below.
2185 			 */
2186 			cpu_hyp_reset();
2187 
2188 		return NOTIFY_OK;
2189 	case CPU_PM_ENTER_FAILED:
2190 	case CPU_PM_EXIT:
2191 		if (__this_cpu_read(kvm_hyp_initialized))
2192 			/* The hyp was enabled before suspend. */
2193 			cpu_hyp_reinit();
2194 
2195 		return NOTIFY_OK;
2196 
2197 	default:
2198 		return NOTIFY_DONE;
2199 	}
2200 }
2201 
2202 static struct notifier_block hyp_init_cpu_pm_nb = {
2203 	.notifier_call = hyp_init_cpu_pm_notifier,
2204 };
2205 
hyp_cpu_pm_init(void)2206 static void __init hyp_cpu_pm_init(void)
2207 {
2208 	if (!is_protected_kvm_enabled())
2209 		cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2210 }
hyp_cpu_pm_exit(void)2211 static void __init hyp_cpu_pm_exit(void)
2212 {
2213 	if (!is_protected_kvm_enabled())
2214 		cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2215 }
2216 #else
hyp_cpu_pm_init(void)2217 static inline void __init hyp_cpu_pm_init(void)
2218 {
2219 }
hyp_cpu_pm_exit(void)2220 static inline void __init hyp_cpu_pm_exit(void)
2221 {
2222 }
2223 #endif
2224 
init_cpu_logical_map(void)2225 static void __init init_cpu_logical_map(void)
2226 {
2227 	unsigned int cpu;
2228 
2229 	/*
2230 	 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2231 	 * Only copy the set of online CPUs whose features have been checked
2232 	 * against the finalized system capabilities. The hypervisor will not
2233 	 * allow any other CPUs from the `possible` set to boot.
2234 	 */
2235 	for_each_online_cpu(cpu)
2236 		hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2237 }
2238 
2239 #define init_psci_0_1_impl_state(config, what)	\
2240 	config.psci_0_1_ ## what ## _implemented = psci_ops.what
2241 
init_psci_relay(void)2242 static bool __init init_psci_relay(void)
2243 {
2244 	/*
2245 	 * If PSCI has not been initialized, protected KVM cannot install
2246 	 * itself on newly booted CPUs.
2247 	 */
2248 	if (!psci_ops.get_version) {
2249 		kvm_err("Cannot initialize protected mode without PSCI\n");
2250 		return false;
2251 	}
2252 
2253 	kvm_host_psci_config.version = psci_ops.get_version();
2254 	kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2255 
2256 	if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2257 		kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2258 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2259 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2260 		init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2261 		init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2262 	}
2263 	return true;
2264 }
2265 
init_subsystems(void)2266 static int __init init_subsystems(void)
2267 {
2268 	int err = 0;
2269 
2270 	/*
2271 	 * Enable hardware so that subsystem initialisation can access EL2.
2272 	 */
2273 	on_each_cpu(cpu_hyp_init, NULL, 1);
2274 
2275 	/*
2276 	 * Register CPU lower-power notifier
2277 	 */
2278 	hyp_cpu_pm_init();
2279 
2280 	/*
2281 	 * Init HYP view of VGIC
2282 	 */
2283 	err = kvm_vgic_hyp_init();
2284 	switch (err) {
2285 	case 0:
2286 		vgic_present = true;
2287 		break;
2288 	case -ENODEV:
2289 	case -ENXIO:
2290 		/*
2291 		 * No VGIC? No pKVM for you.
2292 		 *
2293 		 * Protected mode assumes that VGICv3 is present, so no point
2294 		 * in trying to hobble along if vgic initialization fails.
2295 		 */
2296 		if (is_protected_kvm_enabled())
2297 			goto out;
2298 
2299 		/*
2300 		 * Otherwise, userspace could choose to implement a GIC for its
2301 		 * guest on non-cooperative hardware.
2302 		 */
2303 		vgic_present = false;
2304 		err = 0;
2305 		break;
2306 	default:
2307 		goto out;
2308 	}
2309 
2310 	/*
2311 	 * Init HYP architected timer support
2312 	 */
2313 	err = kvm_timer_hyp_init(vgic_present);
2314 	if (err)
2315 		goto out;
2316 
2317 	kvm_register_perf_callbacks(NULL);
2318 
2319 out:
2320 	if (err)
2321 		hyp_cpu_pm_exit();
2322 
2323 	if (err || !is_protected_kvm_enabled())
2324 		on_each_cpu(cpu_hyp_uninit, NULL, 1);
2325 
2326 	return err;
2327 }
2328 
teardown_subsystems(void)2329 static void __init teardown_subsystems(void)
2330 {
2331 	kvm_unregister_perf_callbacks();
2332 	hyp_cpu_pm_exit();
2333 }
2334 
teardown_hyp_mode(void)2335 static void __init teardown_hyp_mode(void)
2336 {
2337 	bool free_sve = system_supports_sve() && is_protected_kvm_enabled();
2338 	int cpu;
2339 
2340 	free_hyp_pgds();
2341 	for_each_possible_cpu(cpu) {
2342 		free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2343 		free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2344 
2345 		if (free_sve) {
2346 			struct cpu_sve_state *sve_state;
2347 
2348 			sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2349 			free_pages((unsigned long) sve_state, pkvm_host_sve_state_order());
2350 		}
2351 	}
2352 }
2353 
do_pkvm_init(u32 hyp_va_bits)2354 static int __init do_pkvm_init(u32 hyp_va_bits)
2355 {
2356 	void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2357 	int ret;
2358 
2359 	preempt_disable();
2360 	cpu_hyp_init_context();
2361 	ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2362 				num_possible_cpus(), kern_hyp_va(per_cpu_base),
2363 				hyp_va_bits);
2364 	cpu_hyp_init_features();
2365 
2366 	/*
2367 	 * The stub hypercalls are now disabled, so set our local flag to
2368 	 * prevent a later re-init attempt in kvm_arch_enable_virtualization_cpu().
2369 	 */
2370 	__this_cpu_write(kvm_hyp_initialized, 1);
2371 	preempt_enable();
2372 
2373 	return ret;
2374 }
2375 
get_hyp_id_aa64pfr0_el1(void)2376 static u64 get_hyp_id_aa64pfr0_el1(void)
2377 {
2378 	/*
2379 	 * Track whether the system isn't affected by spectre/meltdown in the
2380 	 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2381 	 * Although this is per-CPU, we make it global for simplicity, e.g., not
2382 	 * to have to worry about vcpu migration.
2383 	 *
2384 	 * Unlike for non-protected VMs, userspace cannot override this for
2385 	 * protected VMs.
2386 	 */
2387 	u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2388 
2389 	val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
2390 		 ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
2391 
2392 	val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2),
2393 			  arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2394 	val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3),
2395 			  arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2396 
2397 	return val;
2398 }
2399 
kvm_hyp_init_symbols(void)2400 static void kvm_hyp_init_symbols(void)
2401 {
2402 	kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2403 	kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2404 	kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2405 	kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2406 	kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2407 	kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2408 	kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2409 	kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2410 	kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2411 	kvm_nvhe_sym(__icache_flags) = __icache_flags;
2412 	kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2413 
2414 	/*
2415 	 * Flush entire BSS since part of its data containing init symbols is read
2416 	 * while the MMU is off.
2417 	 */
2418 	kvm_flush_dcache_to_poc(kvm_ksym_ref(__hyp_bss_start),
2419 				kvm_ksym_ref(__hyp_bss_end) - kvm_ksym_ref(__hyp_bss_start));
2420 }
2421 
kvm_hyp_init_protection(u32 hyp_va_bits)2422 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2423 {
2424 	void *addr = phys_to_virt(hyp_mem_base);
2425 	int ret;
2426 
2427 	ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2428 	if (ret)
2429 		return ret;
2430 
2431 	ret = do_pkvm_init(hyp_va_bits);
2432 	if (ret)
2433 		return ret;
2434 
2435 	free_hyp_pgds();
2436 
2437 	return 0;
2438 }
2439 
init_pkvm_host_sve_state(void)2440 static int init_pkvm_host_sve_state(void)
2441 {
2442 	int cpu;
2443 
2444 	if (!system_supports_sve())
2445 		return 0;
2446 
2447 	/* Allocate pages for host sve state in protected mode. */
2448 	for_each_possible_cpu(cpu) {
2449 		struct page *page = alloc_pages(GFP_KERNEL, pkvm_host_sve_state_order());
2450 
2451 		if (!page)
2452 			return -ENOMEM;
2453 
2454 		per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state = page_address(page);
2455 	}
2456 
2457 	/*
2458 	 * Don't map the pages in hyp since these are only used in protected
2459 	 * mode, which will (re)create its own mapping when initialized.
2460 	 */
2461 
2462 	return 0;
2463 }
2464 
2465 /*
2466  * Finalizes the initialization of hyp mode, once everything else is initialized
2467  * and the initialziation process cannot fail.
2468  */
finalize_init_hyp_mode(void)2469 static void finalize_init_hyp_mode(void)
2470 {
2471 	int cpu;
2472 
2473 	if (system_supports_sve() && is_protected_kvm_enabled()) {
2474 		for_each_possible_cpu(cpu) {
2475 			struct cpu_sve_state *sve_state;
2476 
2477 			sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2478 			per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state =
2479 				kern_hyp_va(sve_state);
2480 		}
2481 	}
2482 }
2483 
pkvm_hyp_init_ptrauth(void)2484 static void pkvm_hyp_init_ptrauth(void)
2485 {
2486 	struct kvm_cpu_context *hyp_ctxt;
2487 	int cpu;
2488 
2489 	for_each_possible_cpu(cpu) {
2490 		hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2491 		hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2492 		hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2493 		hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2494 		hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2495 		hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2496 		hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2497 		hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2498 		hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2499 		hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2500 		hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2501 	}
2502 }
2503 
2504 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2505 static int __init init_hyp_mode(void)
2506 {
2507 	u32 hyp_va_bits;
2508 	int cpu;
2509 	int err = -ENOMEM;
2510 
2511 	/*
2512 	 * The protected Hyp-mode cannot be initialized if the memory pool
2513 	 * allocation has failed.
2514 	 */
2515 	if (is_protected_kvm_enabled() && !hyp_mem_base)
2516 		goto out_err;
2517 
2518 	/*
2519 	 * Allocate Hyp PGD and setup Hyp identity mapping
2520 	 */
2521 	err = kvm_mmu_init(&hyp_va_bits);
2522 	if (err)
2523 		goto out_err;
2524 
2525 	/*
2526 	 * Allocate stack pages for Hypervisor-mode
2527 	 */
2528 	for_each_possible_cpu(cpu) {
2529 		unsigned long stack_base;
2530 
2531 		stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2532 		if (!stack_base) {
2533 			err = -ENOMEM;
2534 			goto out_err;
2535 		}
2536 
2537 		per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2538 	}
2539 
2540 	/*
2541 	 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2542 	 */
2543 	for_each_possible_cpu(cpu) {
2544 		struct page *page;
2545 		void *page_addr;
2546 
2547 		page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2548 		if (!page) {
2549 			err = -ENOMEM;
2550 			goto out_err;
2551 		}
2552 
2553 		page_addr = page_address(page);
2554 		memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2555 		kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2556 	}
2557 
2558 	/*
2559 	 * Map the Hyp-code called directly from the host
2560 	 */
2561 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2562 				  kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2563 	if (err) {
2564 		kvm_err("Cannot map world-switch code\n");
2565 		goto out_err;
2566 	}
2567 
2568 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2569 				  kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2570 	if (err) {
2571 		kvm_err("Cannot map .hyp.rodata section\n");
2572 		goto out_err;
2573 	}
2574 
2575 	err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2576 				  kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2577 	if (err) {
2578 		kvm_err("Cannot map rodata section\n");
2579 		goto out_err;
2580 	}
2581 
2582 	/*
2583 	 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2584 	 * section thanks to an assertion in the linker script. Map it RW and
2585 	 * the rest of .bss RO.
2586 	 */
2587 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2588 				  kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2589 	if (err) {
2590 		kvm_err("Cannot map hyp bss section: %d\n", err);
2591 		goto out_err;
2592 	}
2593 
2594 	err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2595 				  kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2596 	if (err) {
2597 		kvm_err("Cannot map bss section\n");
2598 		goto out_err;
2599 	}
2600 
2601 	/*
2602 	 * Map the Hyp stack pages
2603 	 */
2604 	for_each_possible_cpu(cpu) {
2605 		struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2606 		char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2607 
2608 		err = create_hyp_stack(__pa(stack_base), &params->stack_hyp_va);
2609 		if (err) {
2610 			kvm_err("Cannot map hyp stack\n");
2611 			goto out_err;
2612 		}
2613 
2614 		/*
2615 		 * Save the stack PA in nvhe_init_params. This will be needed
2616 		 * to recreate the stack mapping in protected nVHE mode.
2617 		 * __hyp_pa() won't do the right thing there, since the stack
2618 		 * has been mapped in the flexible private VA space.
2619 		 */
2620 		params->stack_pa = __pa(stack_base);
2621 	}
2622 
2623 	for_each_possible_cpu(cpu) {
2624 		char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2625 		char *percpu_end = percpu_begin + nvhe_percpu_size();
2626 
2627 		/* Map Hyp percpu pages */
2628 		err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2629 		if (err) {
2630 			kvm_err("Cannot map hyp percpu region\n");
2631 			goto out_err;
2632 		}
2633 
2634 		/* Prepare the CPU initialization parameters */
2635 		cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2636 	}
2637 
2638 	kvm_hyp_init_symbols();
2639 
2640 	if (is_protected_kvm_enabled()) {
2641 		if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2642 		    cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH))
2643 			pkvm_hyp_init_ptrauth();
2644 
2645 		init_cpu_logical_map();
2646 
2647 		if (!init_psci_relay()) {
2648 			err = -ENODEV;
2649 			goto out_err;
2650 		}
2651 
2652 		err = init_pkvm_host_sve_state();
2653 		if (err)
2654 			goto out_err;
2655 
2656 		err = kvm_hyp_init_protection(hyp_va_bits);
2657 		if (err) {
2658 			kvm_err("Failed to init hyp memory protection\n");
2659 			goto out_err;
2660 		}
2661 	}
2662 
2663 	return 0;
2664 
2665 out_err:
2666 	teardown_hyp_mode();
2667 	kvm_err("error initializing Hyp mode: %d\n", err);
2668 	return err;
2669 }
2670 
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2671 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2672 {
2673 	struct kvm_vcpu *vcpu = NULL;
2674 	struct kvm_mpidr_data *data;
2675 	unsigned long i;
2676 
2677 	mpidr &= MPIDR_HWID_BITMASK;
2678 
2679 	rcu_read_lock();
2680 	data = rcu_dereference(kvm->arch.mpidr_data);
2681 
2682 	if (data) {
2683 		u16 idx = kvm_mpidr_index(data, mpidr);
2684 
2685 		vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]);
2686 		if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu))
2687 			vcpu = NULL;
2688 	}
2689 
2690 	rcu_read_unlock();
2691 
2692 	if (vcpu)
2693 		return vcpu;
2694 
2695 	kvm_for_each_vcpu(i, vcpu, kvm) {
2696 		if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2697 			return vcpu;
2698 	}
2699 	return NULL;
2700 }
2701 
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2702 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2703 {
2704 	return irqchip_in_kernel(kvm);
2705 }
2706 
kvm_arch_has_irq_bypass(void)2707 bool kvm_arch_has_irq_bypass(void)
2708 {
2709 	return true;
2710 }
2711 
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2712 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2713 				      struct irq_bypass_producer *prod)
2714 {
2715 	struct kvm_kernel_irqfd *irqfd =
2716 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2717 
2718 	return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2719 					  &irqfd->irq_entry);
2720 }
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2721 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2722 				      struct irq_bypass_producer *prod)
2723 {
2724 	struct kvm_kernel_irqfd *irqfd =
2725 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2726 
2727 	kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
2728 				     &irqfd->irq_entry);
2729 }
2730 
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2731 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2732 {
2733 	struct kvm_kernel_irqfd *irqfd =
2734 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2735 
2736 	kvm_arm_halt_guest(irqfd->kvm);
2737 }
2738 
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2739 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2740 {
2741 	struct kvm_kernel_irqfd *irqfd =
2742 		container_of(cons, struct kvm_kernel_irqfd, consumer);
2743 
2744 	kvm_arm_resume_guest(irqfd->kvm);
2745 }
2746 
2747 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2748 static __init int kvm_arm_init(void)
2749 {
2750 	int err;
2751 	bool in_hyp_mode;
2752 
2753 	if (!is_hyp_mode_available()) {
2754 		kvm_info("HYP mode not available\n");
2755 		return -ENODEV;
2756 	}
2757 
2758 	if (kvm_get_mode() == KVM_MODE_NONE) {
2759 		kvm_info("KVM disabled from command line\n");
2760 		return -ENODEV;
2761 	}
2762 
2763 	err = kvm_sys_reg_table_init();
2764 	if (err) {
2765 		kvm_info("Error initializing system register tables");
2766 		return err;
2767 	}
2768 
2769 	in_hyp_mode = is_kernel_in_hyp_mode();
2770 
2771 	if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2772 	    cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2773 		kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2774 			 "Only trusted guests should be used on this system.\n");
2775 
2776 	err = kvm_set_ipa_limit();
2777 	if (err)
2778 		return err;
2779 
2780 	err = kvm_arm_init_sve();
2781 	if (err)
2782 		return err;
2783 
2784 	err = kvm_arm_vmid_alloc_init();
2785 	if (err) {
2786 		kvm_err("Failed to initialize VMID allocator.\n");
2787 		return err;
2788 	}
2789 
2790 	if (!in_hyp_mode) {
2791 		err = init_hyp_mode();
2792 		if (err)
2793 			goto out_err;
2794 	}
2795 
2796 	err = kvm_init_vector_slots();
2797 	if (err) {
2798 		kvm_err("Cannot initialise vector slots\n");
2799 		goto out_hyp;
2800 	}
2801 
2802 	err = init_subsystems();
2803 	if (err)
2804 		goto out_hyp;
2805 
2806 	kvm_info("%s%sVHE mode initialized successfully\n",
2807 		 in_hyp_mode ? "" : (is_protected_kvm_enabled() ?
2808 				     "Protected " : "Hyp "),
2809 		 in_hyp_mode ? "" : (cpus_have_final_cap(ARM64_KVM_HVHE) ?
2810 				     "h" : "n"));
2811 
2812 	/*
2813 	 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2814 	 * hypervisor protection is finalized.
2815 	 */
2816 	err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2817 	if (err)
2818 		goto out_subs;
2819 
2820 	/*
2821 	 * This should be called after initialization is done and failure isn't
2822 	 * possible anymore.
2823 	 */
2824 	if (!in_hyp_mode)
2825 		finalize_init_hyp_mode();
2826 
2827 	kvm_arm_initialised = true;
2828 
2829 	return 0;
2830 
2831 out_subs:
2832 	teardown_subsystems();
2833 out_hyp:
2834 	if (!in_hyp_mode)
2835 		teardown_hyp_mode();
2836 out_err:
2837 	kvm_arm_vmid_alloc_free();
2838 	return err;
2839 }
2840 
early_kvm_mode_cfg(char * arg)2841 static int __init early_kvm_mode_cfg(char *arg)
2842 {
2843 	if (!arg)
2844 		return -EINVAL;
2845 
2846 	if (strcmp(arg, "none") == 0) {
2847 		kvm_mode = KVM_MODE_NONE;
2848 		return 0;
2849 	}
2850 
2851 	if (!is_hyp_mode_available()) {
2852 		pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2853 		return 0;
2854 	}
2855 
2856 	if (strcmp(arg, "protected") == 0) {
2857 		if (!is_kernel_in_hyp_mode())
2858 			kvm_mode = KVM_MODE_PROTECTED;
2859 		else
2860 			pr_warn_once("Protected KVM not available with VHE\n");
2861 
2862 		return 0;
2863 	}
2864 
2865 	if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2866 		kvm_mode = KVM_MODE_DEFAULT;
2867 		return 0;
2868 	}
2869 
2870 	if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2871 		kvm_mode = KVM_MODE_NV;
2872 		return 0;
2873 	}
2874 
2875 	return -EINVAL;
2876 }
2877 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2878 
early_kvm_wfx_trap_policy_cfg(char * arg,enum kvm_wfx_trap_policy * p)2879 static int __init early_kvm_wfx_trap_policy_cfg(char *arg, enum kvm_wfx_trap_policy *p)
2880 {
2881 	if (!arg)
2882 		return -EINVAL;
2883 
2884 	if (strcmp(arg, "trap") == 0) {
2885 		*p = KVM_WFX_TRAP;
2886 		return 0;
2887 	}
2888 
2889 	if (strcmp(arg, "notrap") == 0) {
2890 		*p = KVM_WFX_NOTRAP;
2891 		return 0;
2892 	}
2893 
2894 	return -EINVAL;
2895 }
2896 
early_kvm_wfi_trap_policy_cfg(char * arg)2897 static int __init early_kvm_wfi_trap_policy_cfg(char *arg)
2898 {
2899 	return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfi_trap_policy);
2900 }
2901 early_param("kvm-arm.wfi_trap_policy", early_kvm_wfi_trap_policy_cfg);
2902 
early_kvm_wfe_trap_policy_cfg(char * arg)2903 static int __init early_kvm_wfe_trap_policy_cfg(char *arg)
2904 {
2905 	return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfe_trap_policy);
2906 }
2907 early_param("kvm-arm.wfe_trap_policy", early_kvm_wfe_trap_policy_cfg);
2908 
kvm_get_mode(void)2909 enum kvm_mode kvm_get_mode(void)
2910 {
2911 	return kvm_mode;
2912 }
2913 
2914 module_init(kvm_arm_init);
2915