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