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/errno.h>
10 #include <linux/err.h>
11 #include <linux/kvm_host.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/vmalloc.h>
15 #include <linux/fs.h>
16 #include <linux/mman.h>
17 #include <linux/sched.h>
18 #include <linux/kvm.h>
19 #include <linux/kvm_irqfd.h>
20 #include <linux/irqbypass.h>
21 #include <linux/sched/stat.h>
22 #include <linux/psci.h>
23 #include <trace/events/kvm.h>
24
25 #define CREATE_TRACE_POINTS
26 #include "trace_arm.h"
27
28 #include <linux/uaccess.h>
29 #include <asm/ptrace.h>
30 #include <asm/mman.h>
31 #include <asm/tlbflush.h>
32 #include <asm/cacheflush.h>
33 #include <asm/cpufeature.h>
34 #include <asm/virt.h>
35 #include <asm/kvm_arm.h>
36 #include <asm/kvm_asm.h>
37 #include <asm/kvm_emulate.h>
38 #include <asm/kvm_mmu.h>
39 #include <asm/kvm_nested.h>
40 #include <asm/kvm_pkvm.h>
41 #include <asm/kvm_ptrauth.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 #include "sys_regs.h"
49
50 static enum kvm_mode kvm_mode = KVM_MODE_DEFAULT;
51
52 enum kvm_wfx_trap_policy {
53 KVM_WFX_NOTRAP_SINGLE_TASK, /* Default option */
54 KVM_WFX_NOTRAP,
55 KVM_WFX_TRAP,
56 };
57
58 static enum kvm_wfx_trap_policy kvm_wfi_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
59 static enum kvm_wfx_trap_policy kvm_wfe_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK;
60
61 DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector);
62
63 DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_base);
64 DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
65
66 DECLARE_KVM_NVHE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
67
68 static bool vgic_present, kvm_arm_initialised;
69
70 static DEFINE_PER_CPU(unsigned char, kvm_hyp_initialized);
71
is_kvm_arm_initialised(void)72 bool is_kvm_arm_initialised(void)
73 {
74 return kvm_arm_initialised;
75 }
76
kvm_arch_vcpu_should_kick(struct kvm_vcpu * vcpu)77 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
78 {
79 return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
80 }
81
kvm_vm_ioctl_enable_cap(struct kvm * kvm,struct kvm_enable_cap * cap)82 int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
83 struct kvm_enable_cap *cap)
84 {
85 int r = -EINVAL;
86
87 if (cap->flags)
88 return -EINVAL;
89
90 if (kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(cap->cap))
91 return -EINVAL;
92
93 switch (cap->cap) {
94 case KVM_CAP_ARM_NISV_TO_USER:
95 r = 0;
96 set_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
97 &kvm->arch.flags);
98 break;
99 case KVM_CAP_ARM_MTE:
100 mutex_lock(&kvm->lock);
101 if (system_supports_mte() && !kvm->created_vcpus) {
102 r = 0;
103 set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags);
104 }
105 mutex_unlock(&kvm->lock);
106 break;
107 case KVM_CAP_ARM_SYSTEM_SUSPEND:
108 r = 0;
109 set_bit(KVM_ARCH_FLAG_SYSTEM_SUSPEND_ENABLED, &kvm->arch.flags);
110 break;
111 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
112 mutex_lock(&kvm->slots_lock);
113 /*
114 * To keep things simple, allow changing the chunk
115 * size only when no memory slots have been created.
116 */
117 if (kvm_are_all_memslots_empty(kvm)) {
118 u64 new_cap = cap->args[0];
119
120 if (!new_cap || kvm_is_block_size_supported(new_cap)) {
121 r = 0;
122 kvm->arch.mmu.split_page_chunk_size = new_cap;
123 }
124 }
125 mutex_unlock(&kvm->slots_lock);
126 break;
127 case KVM_CAP_ARM_WRITABLE_IMP_ID_REGS:
128 mutex_lock(&kvm->lock);
129 if (!kvm->created_vcpus) {
130 r = 0;
131 set_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &kvm->arch.flags);
132 }
133 mutex_unlock(&kvm->lock);
134 break;
135 default:
136 break;
137 }
138
139 return r;
140 }
141
kvm_arm_default_max_vcpus(void)142 static int kvm_arm_default_max_vcpus(void)
143 {
144 return vgic_present ? kvm_vgic_get_max_vcpus() : KVM_MAX_VCPUS;
145 }
146
147 /**
148 * kvm_arch_init_vm - initializes a VM data structure
149 * @kvm: pointer to the KVM struct
150 * @type: kvm device type
151 */
kvm_arch_init_vm(struct kvm * kvm,unsigned long type)152 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
153 {
154 int ret;
155
156 mutex_init(&kvm->arch.config_lock);
157
158 #ifdef CONFIG_LOCKDEP
159 /* Clue in lockdep that the config_lock must be taken inside kvm->lock */
160 mutex_lock(&kvm->lock);
161 mutex_lock(&kvm->arch.config_lock);
162 mutex_unlock(&kvm->arch.config_lock);
163 mutex_unlock(&kvm->lock);
164 #endif
165
166 kvm_init_nested(kvm);
167
168 ret = kvm_share_hyp(kvm, kvm + 1);
169 if (ret)
170 return ret;
171
172 if (!zalloc_cpumask_var(&kvm->arch.supported_cpus, GFP_KERNEL_ACCOUNT)) {
173 ret = -ENOMEM;
174 goto err_unshare_kvm;
175 }
176 cpumask_copy(kvm->arch.supported_cpus, cpu_possible_mask);
177
178 ret = kvm_init_stage2_mmu(kvm, &kvm->arch.mmu, type);
179 if (ret)
180 goto err_free_cpumask;
181
182 if (is_protected_kvm_enabled()) {
183 /*
184 * If any failures occur after this is successful, make sure to
185 * call __pkvm_unreserve_vm to unreserve the VM in hyp.
186 */
187 ret = pkvm_init_host_vm(kvm);
188 if (ret)
189 goto err_free_cpumask;
190 }
191
192 kvm_vgic_early_init(kvm);
193
194 kvm_timer_init_vm(kvm);
195
196 /* The maximum number of VCPUs is limited by the host's GIC model */
197 kvm->max_vcpus = kvm_arm_default_max_vcpus();
198
199 kvm_arm_init_hypercalls(kvm);
200
201 bitmap_zero(kvm->arch.vcpu_features, KVM_VCPU_MAX_FEATURES);
202
203 return 0;
204
205 err_free_cpumask:
206 free_cpumask_var(kvm->arch.supported_cpus);
207 err_unshare_kvm:
208 kvm_unshare_hyp(kvm, kvm + 1);
209 return ret;
210 }
211
kvm_arch_vcpu_fault(struct kvm_vcpu * vcpu,struct vm_fault * vmf)212 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
213 {
214 return VM_FAULT_SIGBUS;
215 }
216
kvm_arch_create_vm_debugfs(struct kvm * kvm)217 void kvm_arch_create_vm_debugfs(struct kvm *kvm)
218 {
219 kvm_sys_regs_create_debugfs(kvm);
220 kvm_s2_ptdump_create_debugfs(kvm);
221 }
222
kvm_destroy_mpidr_data(struct kvm * kvm)223 static void kvm_destroy_mpidr_data(struct kvm *kvm)
224 {
225 struct kvm_mpidr_data *data;
226
227 mutex_lock(&kvm->arch.config_lock);
228
229 data = rcu_dereference_protected(kvm->arch.mpidr_data,
230 lockdep_is_held(&kvm->arch.config_lock));
231 if (data) {
232 rcu_assign_pointer(kvm->arch.mpidr_data, NULL);
233 synchronize_rcu();
234 kfree(data);
235 }
236
237 mutex_unlock(&kvm->arch.config_lock);
238 }
239
240 /**
241 * kvm_arch_destroy_vm - destroy the VM data structure
242 * @kvm: pointer to the KVM struct
243 */
kvm_arch_destroy_vm(struct kvm * kvm)244 void kvm_arch_destroy_vm(struct kvm *kvm)
245 {
246 bitmap_free(kvm->arch.pmu_filter);
247 free_cpumask_var(kvm->arch.supported_cpus);
248
249 kvm_vgic_destroy(kvm);
250
251 if (is_protected_kvm_enabled())
252 pkvm_destroy_hyp_vm(kvm);
253
254 kvm_destroy_mpidr_data(kvm);
255
256 kfree(kvm->arch.sysreg_masks);
257 kvm_destroy_vcpus(kvm);
258
259 kvm_unshare_hyp(kvm, kvm + 1);
260
261 kvm_arm_teardown_hypercalls(kvm);
262 }
263
kvm_has_full_ptr_auth(void)264 static bool kvm_has_full_ptr_auth(void)
265 {
266 bool apa, gpa, api, gpi, apa3, gpa3;
267 u64 isar1, isar2, val;
268
269 /*
270 * Check that:
271 *
272 * - both Address and Generic auth are implemented for a given
273 * algorithm (Q5, IMPDEF or Q3)
274 * - only a single algorithm is implemented.
275 */
276 if (!system_has_full_ptr_auth())
277 return false;
278
279 isar1 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
280 isar2 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
281
282 apa = !!FIELD_GET(ID_AA64ISAR1_EL1_APA_MASK, isar1);
283 val = FIELD_GET(ID_AA64ISAR1_EL1_GPA_MASK, isar1);
284 gpa = (val == ID_AA64ISAR1_EL1_GPA_IMP);
285
286 api = !!FIELD_GET(ID_AA64ISAR1_EL1_API_MASK, isar1);
287 val = FIELD_GET(ID_AA64ISAR1_EL1_GPI_MASK, isar1);
288 gpi = (val == ID_AA64ISAR1_EL1_GPI_IMP);
289
290 apa3 = !!FIELD_GET(ID_AA64ISAR2_EL1_APA3_MASK, isar2);
291 val = FIELD_GET(ID_AA64ISAR2_EL1_GPA3_MASK, isar2);
292 gpa3 = (val == ID_AA64ISAR2_EL1_GPA3_IMP);
293
294 return (apa == gpa && api == gpi && apa3 == gpa3 &&
295 (apa + api + apa3) == 1);
296 }
297
kvm_vm_ioctl_check_extension(struct kvm * kvm,long ext)298 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
299 {
300 int r;
301
302 if (kvm && kvm_vm_is_protected(kvm) && !kvm_pvm_ext_allowed(ext))
303 return 0;
304
305 switch (ext) {
306 case KVM_CAP_IRQCHIP:
307 r = vgic_present;
308 break;
309 case KVM_CAP_IOEVENTFD:
310 case KVM_CAP_USER_MEMORY:
311 case KVM_CAP_SYNC_MMU:
312 case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
313 case KVM_CAP_ONE_REG:
314 case KVM_CAP_ARM_PSCI:
315 case KVM_CAP_ARM_PSCI_0_2:
316 case KVM_CAP_READONLY_MEM:
317 case KVM_CAP_MP_STATE:
318 case KVM_CAP_IMMEDIATE_EXIT:
319 case KVM_CAP_VCPU_EVENTS:
320 case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2:
321 case KVM_CAP_ARM_NISV_TO_USER:
322 case KVM_CAP_ARM_INJECT_EXT_DABT:
323 case KVM_CAP_SET_GUEST_DEBUG:
324 case KVM_CAP_VCPU_ATTRIBUTES:
325 case KVM_CAP_PTP_KVM:
326 case KVM_CAP_ARM_SYSTEM_SUSPEND:
327 case KVM_CAP_IRQFD_RESAMPLE:
328 case KVM_CAP_COUNTER_OFFSET:
329 case KVM_CAP_ARM_WRITABLE_IMP_ID_REGS:
330 r = 1;
331 break;
332 case KVM_CAP_SET_GUEST_DEBUG2:
333 return KVM_GUESTDBG_VALID_MASK;
334 case KVM_CAP_ARM_SET_DEVICE_ADDR:
335 r = 1;
336 break;
337 case KVM_CAP_NR_VCPUS:
338 /*
339 * ARM64 treats KVM_CAP_NR_CPUS differently from all other
340 * architectures, as it does not always bound it to
341 * KVM_CAP_MAX_VCPUS. It should not matter much because
342 * this is just an advisory value.
343 */
344 r = min_t(unsigned int, num_online_cpus(),
345 kvm_arm_default_max_vcpus());
346 break;
347 case KVM_CAP_MAX_VCPUS:
348 case KVM_CAP_MAX_VCPU_ID:
349 if (kvm)
350 r = kvm->max_vcpus;
351 else
352 r = kvm_arm_default_max_vcpus();
353 break;
354 case KVM_CAP_MSI_DEVID:
355 if (!kvm)
356 r = -EINVAL;
357 else
358 r = kvm->arch.vgic.msis_require_devid;
359 break;
360 case KVM_CAP_ARM_USER_IRQ:
361 /*
362 * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
363 * (bump this number if adding more devices)
364 */
365 r = 1;
366 break;
367 case KVM_CAP_ARM_MTE:
368 r = system_supports_mte();
369 break;
370 case KVM_CAP_STEAL_TIME:
371 r = kvm_arm_pvtime_supported();
372 break;
373 case KVM_CAP_ARM_EL1_32BIT:
374 r = cpus_have_final_cap(ARM64_HAS_32BIT_EL1);
375 break;
376 case KVM_CAP_ARM_EL2:
377 r = cpus_have_final_cap(ARM64_HAS_NESTED_VIRT);
378 break;
379 case KVM_CAP_ARM_EL2_E2H0:
380 r = cpus_have_final_cap(ARM64_HAS_HCR_NV1);
381 break;
382 case KVM_CAP_GUEST_DEBUG_HW_BPS:
383 r = get_num_brps();
384 break;
385 case KVM_CAP_GUEST_DEBUG_HW_WPS:
386 r = get_num_wrps();
387 break;
388 case KVM_CAP_ARM_PMU_V3:
389 r = kvm_supports_guest_pmuv3();
390 break;
391 case KVM_CAP_ARM_INJECT_SERROR_ESR:
392 r = cpus_have_final_cap(ARM64_HAS_RAS_EXTN);
393 break;
394 case KVM_CAP_ARM_VM_IPA_SIZE:
395 r = get_kvm_ipa_limit();
396 break;
397 case KVM_CAP_ARM_SVE:
398 r = system_supports_sve();
399 break;
400 case KVM_CAP_ARM_PTRAUTH_ADDRESS:
401 case KVM_CAP_ARM_PTRAUTH_GENERIC:
402 r = kvm_has_full_ptr_auth();
403 break;
404 case KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE:
405 if (kvm)
406 r = kvm->arch.mmu.split_page_chunk_size;
407 else
408 r = KVM_ARM_EAGER_SPLIT_CHUNK_SIZE_DEFAULT;
409 break;
410 case KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES:
411 r = kvm_supported_block_sizes();
412 break;
413 case KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES:
414 r = BIT(0);
415 break;
416 case KVM_CAP_ARM_CACHEABLE_PFNMAP_SUPPORTED:
417 if (!kvm)
418 r = -EINVAL;
419 else
420 r = kvm_supports_cacheable_pfnmap();
421 break;
422
423 default:
424 r = 0;
425 }
426
427 return r;
428 }
429
kvm_arch_dev_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)430 long kvm_arch_dev_ioctl(struct file *filp,
431 unsigned int ioctl, unsigned long arg)
432 {
433 return -EINVAL;
434 }
435
kvm_arch_alloc_vm(void)436 struct kvm *kvm_arch_alloc_vm(void)
437 {
438 size_t sz = sizeof(struct kvm);
439
440 if (!has_vhe())
441 return kzalloc(sz, GFP_KERNEL_ACCOUNT);
442
443 return __vmalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM | __GFP_ZERO);
444 }
445
kvm_arch_vcpu_precreate(struct kvm * kvm,unsigned int id)446 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
447 {
448 if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
449 return -EBUSY;
450
451 if (id >= kvm->max_vcpus)
452 return -EINVAL;
453
454 return 0;
455 }
456
kvm_arch_vcpu_create(struct kvm_vcpu * vcpu)457 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
458 {
459 int err;
460
461 spin_lock_init(&vcpu->arch.mp_state_lock);
462
463 #ifdef CONFIG_LOCKDEP
464 /* Inform lockdep that the config_lock is acquired after vcpu->mutex */
465 mutex_lock(&vcpu->mutex);
466 mutex_lock(&vcpu->kvm->arch.config_lock);
467 mutex_unlock(&vcpu->kvm->arch.config_lock);
468 mutex_unlock(&vcpu->mutex);
469 #endif
470
471 /* Force users to call KVM_ARM_VCPU_INIT */
472 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
473
474 vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
475
476 /* Set up the timer */
477 kvm_timer_vcpu_init(vcpu);
478
479 kvm_pmu_vcpu_init(vcpu);
480
481 kvm_arm_pvtime_vcpu_init(&vcpu->arch);
482
483 vcpu->arch.hw_mmu = &vcpu->kvm->arch.mmu;
484
485 /*
486 * This vCPU may have been created after mpidr_data was initialized.
487 * Throw out the pre-computed mappings if that is the case which forces
488 * KVM to fall back to iteratively searching the vCPUs.
489 */
490 kvm_destroy_mpidr_data(vcpu->kvm);
491
492 err = kvm_vgic_vcpu_init(vcpu);
493 if (err)
494 return err;
495
496 err = kvm_share_hyp(vcpu, vcpu + 1);
497 if (err)
498 kvm_vgic_vcpu_destroy(vcpu);
499
500 return err;
501 }
502
kvm_arch_vcpu_postcreate(struct kvm_vcpu * vcpu)503 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
504 {
505 }
506
kvm_arch_vcpu_destroy(struct kvm_vcpu * vcpu)507 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
508 {
509 if (!is_protected_kvm_enabled())
510 kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
511 else
512 free_hyp_memcache(&vcpu->arch.pkvm_memcache);
513 kvm_timer_vcpu_terminate(vcpu);
514 kvm_pmu_vcpu_destroy(vcpu);
515 kvm_vgic_vcpu_destroy(vcpu);
516 kvm_arm_vcpu_destroy(vcpu);
517 }
518
kvm_arch_vcpu_blocking(struct kvm_vcpu * vcpu)519 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
520 {
521
522 }
523
kvm_arch_vcpu_unblocking(struct kvm_vcpu * vcpu)524 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
525 {
526
527 }
528
vcpu_set_pauth_traps(struct kvm_vcpu * vcpu)529 static void vcpu_set_pauth_traps(struct kvm_vcpu *vcpu)
530 {
531 if (vcpu_has_ptrauth(vcpu) && !is_protected_kvm_enabled()) {
532 /*
533 * Either we're running an L2 guest, and the API/APK bits come
534 * from L1's HCR_EL2, or API/APK are both set.
535 */
536 if (unlikely(is_nested_ctxt(vcpu))) {
537 u64 val;
538
539 val = __vcpu_sys_reg(vcpu, HCR_EL2);
540 val &= (HCR_API | HCR_APK);
541 vcpu->arch.hcr_el2 &= ~(HCR_API | HCR_APK);
542 vcpu->arch.hcr_el2 |= val;
543 } else {
544 vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK);
545 }
546
547 /*
548 * Save the host keys if there is any chance for the guest
549 * to use pauth, as the entry code will reload the guest
550 * keys in that case.
551 */
552 if (vcpu->arch.hcr_el2 & (HCR_API | HCR_APK)) {
553 struct kvm_cpu_context *ctxt;
554
555 ctxt = this_cpu_ptr_hyp_sym(kvm_hyp_ctxt);
556 ptrauth_save_keys(ctxt);
557 }
558 }
559 }
560
kvm_vcpu_should_clear_twi(struct kvm_vcpu * vcpu)561 static bool kvm_vcpu_should_clear_twi(struct kvm_vcpu *vcpu)
562 {
563 if (unlikely(kvm_wfi_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
564 return kvm_wfi_trap_policy == KVM_WFX_NOTRAP;
565
566 return single_task_running() &&
567 (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
568 vcpu->kvm->arch.vgic.nassgireq);
569 }
570
kvm_vcpu_should_clear_twe(struct kvm_vcpu * vcpu)571 static bool kvm_vcpu_should_clear_twe(struct kvm_vcpu *vcpu)
572 {
573 if (unlikely(kvm_wfe_trap_policy != KVM_WFX_NOTRAP_SINGLE_TASK))
574 return kvm_wfe_trap_policy == KVM_WFX_NOTRAP;
575
576 return single_task_running();
577 }
578
kvm_arch_vcpu_load(struct kvm_vcpu * vcpu,int cpu)579 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
580 {
581 struct kvm_s2_mmu *mmu;
582 int *last_ran;
583
584 if (is_protected_kvm_enabled())
585 goto nommu;
586
587 if (vcpu_has_nv(vcpu))
588 kvm_vcpu_load_hw_mmu(vcpu);
589
590 mmu = vcpu->arch.hw_mmu;
591 last_ran = this_cpu_ptr(mmu->last_vcpu_ran);
592
593 /*
594 * Ensure a VMID is allocated for the MMU before programming VTTBR_EL2,
595 * which happens eagerly in VHE.
596 *
597 * Also, the VMID allocator only preserves VMIDs that are active at the
598 * time of rollover, so KVM might need to grab a new VMID for the MMU if
599 * this is called from kvm_sched_in().
600 */
601 kvm_arm_vmid_update(&mmu->vmid);
602
603 /*
604 * We guarantee that both TLBs and I-cache are private to each
605 * vcpu. If detecting that a vcpu from the same VM has
606 * previously run on the same physical CPU, call into the
607 * hypervisor code to nuke the relevant contexts.
608 *
609 * We might get preempted before the vCPU actually runs, but
610 * over-invalidation doesn't affect correctness.
611 */
612 if (*last_ran != vcpu->vcpu_idx) {
613 kvm_call_hyp(__kvm_flush_cpu_context, mmu);
614 *last_ran = vcpu->vcpu_idx;
615 }
616
617 nommu:
618 vcpu->cpu = cpu;
619
620 /*
621 * The timer must be loaded before the vgic to correctly set up physical
622 * interrupt deactivation in nested state (e.g. timer interrupt).
623 */
624 kvm_timer_vcpu_load(vcpu);
625 kvm_vgic_load(vcpu);
626 kvm_vcpu_load_debug(vcpu);
627 if (has_vhe())
628 kvm_vcpu_load_vhe(vcpu);
629 kvm_arch_vcpu_load_fp(vcpu);
630 kvm_vcpu_pmu_restore_guest(vcpu);
631 if (kvm_arm_is_pvtime_enabled(&vcpu->arch))
632 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
633
634 if (kvm_vcpu_should_clear_twe(vcpu))
635 vcpu->arch.hcr_el2 &= ~HCR_TWE;
636 else
637 vcpu->arch.hcr_el2 |= HCR_TWE;
638
639 if (kvm_vcpu_should_clear_twi(vcpu))
640 vcpu->arch.hcr_el2 &= ~HCR_TWI;
641 else
642 vcpu->arch.hcr_el2 |= HCR_TWI;
643
644 vcpu_set_pauth_traps(vcpu);
645 kvm_vcpu_load_fgt(vcpu);
646
647 if (is_protected_kvm_enabled()) {
648 kvm_call_hyp_nvhe(__pkvm_vcpu_load,
649 vcpu->kvm->arch.pkvm.handle,
650 vcpu->vcpu_idx, vcpu->arch.hcr_el2);
651 kvm_call_hyp(__vgic_v3_restore_vmcr_aprs,
652 &vcpu->arch.vgic_cpu.vgic_v3);
653 }
654
655 if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus))
656 vcpu_set_on_unsupported_cpu(vcpu);
657 }
658
kvm_arch_vcpu_put(struct kvm_vcpu * vcpu)659 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
660 {
661 if (is_protected_kvm_enabled()) {
662 kvm_call_hyp(__vgic_v3_save_vmcr_aprs,
663 &vcpu->arch.vgic_cpu.vgic_v3);
664 kvm_call_hyp_nvhe(__pkvm_vcpu_put);
665 }
666
667 kvm_vcpu_put_debug(vcpu);
668 kvm_arch_vcpu_put_fp(vcpu);
669 if (has_vhe())
670 kvm_vcpu_put_vhe(vcpu);
671 kvm_timer_vcpu_put(vcpu);
672 kvm_vgic_put(vcpu);
673 kvm_vcpu_pmu_restore_host(vcpu);
674 if (vcpu_has_nv(vcpu))
675 kvm_vcpu_put_hw_mmu(vcpu);
676 kvm_arm_vmid_clear_active();
677
678 vcpu_clear_on_unsupported_cpu(vcpu);
679 vcpu->cpu = -1;
680 }
681
__kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)682 static void __kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
683 {
684 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED);
685 kvm_make_request(KVM_REQ_SLEEP, vcpu);
686 kvm_vcpu_kick(vcpu);
687 }
688
kvm_arm_vcpu_power_off(struct kvm_vcpu * vcpu)689 void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
690 {
691 spin_lock(&vcpu->arch.mp_state_lock);
692 __kvm_arm_vcpu_power_off(vcpu);
693 spin_unlock(&vcpu->arch.mp_state_lock);
694 }
695
kvm_arm_vcpu_stopped(struct kvm_vcpu * vcpu)696 bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu)
697 {
698 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED;
699 }
700
kvm_arm_vcpu_suspend(struct kvm_vcpu * vcpu)701 static void kvm_arm_vcpu_suspend(struct kvm_vcpu *vcpu)
702 {
703 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_SUSPENDED);
704 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
705 kvm_vcpu_kick(vcpu);
706 }
707
kvm_arm_vcpu_suspended(struct kvm_vcpu * vcpu)708 static bool kvm_arm_vcpu_suspended(struct kvm_vcpu *vcpu)
709 {
710 return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_SUSPENDED;
711 }
712
kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)713 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
714 struct kvm_mp_state *mp_state)
715 {
716 *mp_state = READ_ONCE(vcpu->arch.mp_state);
717
718 return 0;
719 }
720
kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu * vcpu,struct kvm_mp_state * mp_state)721 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
722 struct kvm_mp_state *mp_state)
723 {
724 int ret = 0;
725
726 spin_lock(&vcpu->arch.mp_state_lock);
727
728 switch (mp_state->mp_state) {
729 case KVM_MP_STATE_RUNNABLE:
730 WRITE_ONCE(vcpu->arch.mp_state, *mp_state);
731 break;
732 case KVM_MP_STATE_STOPPED:
733 __kvm_arm_vcpu_power_off(vcpu);
734 break;
735 case KVM_MP_STATE_SUSPENDED:
736 kvm_arm_vcpu_suspend(vcpu);
737 break;
738 default:
739 ret = -EINVAL;
740 }
741
742 spin_unlock(&vcpu->arch.mp_state_lock);
743
744 return ret;
745 }
746
747 /**
748 * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
749 * @v: The VCPU pointer
750 *
751 * If the guest CPU is not waiting for interrupts or an interrupt line is
752 * asserted, the CPU is by definition runnable.
753 */
kvm_arch_vcpu_runnable(struct kvm_vcpu * v)754 int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
755 {
756 bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF | HCR_VSE);
757
758 return ((irq_lines || kvm_vgic_vcpu_pending_irq(v))
759 && !kvm_arm_vcpu_stopped(v) && !v->arch.pause);
760 }
761
kvm_arch_vcpu_in_kernel(struct kvm_vcpu * vcpu)762 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
763 {
764 return vcpu_mode_priv(vcpu);
765 }
766
767 #ifdef CONFIG_GUEST_PERF_EVENTS
kvm_arch_vcpu_get_ip(struct kvm_vcpu * vcpu)768 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu)
769 {
770 return *vcpu_pc(vcpu);
771 }
772 #endif
773
kvm_init_mpidr_data(struct kvm * kvm)774 static void kvm_init_mpidr_data(struct kvm *kvm)
775 {
776 struct kvm_mpidr_data *data = NULL;
777 unsigned long c, mask, nr_entries;
778 u64 aff_set = 0, aff_clr = ~0UL;
779 struct kvm_vcpu *vcpu;
780
781 mutex_lock(&kvm->arch.config_lock);
782
783 if (rcu_access_pointer(kvm->arch.mpidr_data) ||
784 atomic_read(&kvm->online_vcpus) == 1)
785 goto out;
786
787 kvm_for_each_vcpu(c, vcpu, kvm) {
788 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
789 aff_set |= aff;
790 aff_clr &= aff;
791 }
792
793 /*
794 * A significant bit can be either 0 or 1, and will only appear in
795 * aff_set. Use aff_clr to weed out the useless stuff.
796 */
797 mask = aff_set ^ aff_clr;
798 nr_entries = BIT_ULL(hweight_long(mask));
799
800 /*
801 * Don't let userspace fool us. If we need more than a single page
802 * to describe the compressed MPIDR array, just fall back to the
803 * iterative method. Single vcpu VMs do not need this either.
804 */
805 if (struct_size(data, cmpidr_to_idx, nr_entries) <= PAGE_SIZE)
806 data = kzalloc(struct_size(data, cmpidr_to_idx, nr_entries),
807 GFP_KERNEL_ACCOUNT);
808
809 if (!data)
810 goto out;
811
812 data->mpidr_mask = mask;
813
814 kvm_for_each_vcpu(c, vcpu, kvm) {
815 u64 aff = kvm_vcpu_get_mpidr_aff(vcpu);
816 u16 index = kvm_mpidr_index(data, aff);
817
818 data->cmpidr_to_idx[index] = c;
819 }
820
821 rcu_assign_pointer(kvm->arch.mpidr_data, data);
822 out:
823 mutex_unlock(&kvm->arch.config_lock);
824 }
825
826 /*
827 * Handle both the initialisation that is being done when the vcpu is
828 * run for the first time, as well as the updates that must be
829 * performed each time we get a new thread dealing with this vcpu.
830 */
kvm_arch_vcpu_run_pid_change(struct kvm_vcpu * vcpu)831 int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
832 {
833 struct kvm *kvm = vcpu->kvm;
834 int ret;
835
836 if (!kvm_vcpu_initialized(vcpu))
837 return -ENOEXEC;
838
839 if (!kvm_arm_vcpu_is_finalized(vcpu))
840 return -EPERM;
841
842 if (likely(vcpu_has_run_once(vcpu)))
843 return 0;
844
845 kvm_init_mpidr_data(kvm);
846
847 if (likely(irqchip_in_kernel(kvm))) {
848 /*
849 * Map the VGIC hardware resources before running a vcpu the
850 * first time on this VM.
851 */
852 ret = kvm_vgic_map_resources(kvm);
853 if (ret)
854 return ret;
855 }
856
857 ret = kvm_finalize_sys_regs(vcpu);
858 if (ret)
859 return ret;
860
861 if (vcpu_has_nv(vcpu)) {
862 ret = kvm_vcpu_allocate_vncr_tlb(vcpu);
863 if (ret)
864 return ret;
865
866 ret = kvm_vgic_vcpu_nv_init(vcpu);
867 if (ret)
868 return ret;
869 }
870
871 /*
872 * This needs to happen after any restriction has been applied
873 * to the feature set.
874 */
875 kvm_calculate_traps(vcpu);
876
877 ret = kvm_timer_enable(vcpu);
878 if (ret)
879 return ret;
880
881 if (kvm_vcpu_has_pmu(vcpu)) {
882 ret = kvm_arm_pmu_v3_enable(vcpu);
883 if (ret)
884 return ret;
885 }
886
887 if (is_protected_kvm_enabled()) {
888 ret = pkvm_create_hyp_vm(kvm);
889 if (ret)
890 return ret;
891
892 ret = pkvm_create_hyp_vcpu(vcpu);
893 if (ret)
894 return ret;
895 }
896
897 mutex_lock(&kvm->arch.config_lock);
898 set_bit(KVM_ARCH_FLAG_HAS_RAN_ONCE, &kvm->arch.flags);
899 mutex_unlock(&kvm->arch.config_lock);
900
901 return ret;
902 }
903
kvm_arch_intc_initialized(struct kvm * kvm)904 bool kvm_arch_intc_initialized(struct kvm *kvm)
905 {
906 return vgic_initialized(kvm);
907 }
908
kvm_arm_halt_guest(struct kvm * kvm)909 void kvm_arm_halt_guest(struct kvm *kvm)
910 {
911 unsigned long i;
912 struct kvm_vcpu *vcpu;
913
914 kvm_for_each_vcpu(i, vcpu, kvm)
915 vcpu->arch.pause = true;
916 kvm_make_all_cpus_request(kvm, KVM_REQ_SLEEP);
917 }
918
kvm_arm_resume_guest(struct kvm * kvm)919 void kvm_arm_resume_guest(struct kvm *kvm)
920 {
921 unsigned long i;
922 struct kvm_vcpu *vcpu;
923
924 kvm_for_each_vcpu(i, vcpu, kvm) {
925 vcpu->arch.pause = false;
926 __kvm_vcpu_wake_up(vcpu);
927 }
928 }
929
kvm_vcpu_sleep(struct kvm_vcpu * vcpu)930 static void kvm_vcpu_sleep(struct kvm_vcpu *vcpu)
931 {
932 struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
933
934 rcuwait_wait_event(wait,
935 (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause),
936 TASK_INTERRUPTIBLE);
937
938 if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) {
939 /* Awaken to handle a signal, request we sleep again later. */
940 kvm_make_request(KVM_REQ_SLEEP, vcpu);
941 }
942
943 /*
944 * Make sure we will observe a potential reset request if we've
945 * observed a change to the power state. Pairs with the smp_wmb() in
946 * kvm_psci_vcpu_on().
947 */
948 smp_rmb();
949 }
950
951 /**
952 * kvm_vcpu_wfi - emulate Wait-For-Interrupt behavior
953 * @vcpu: The VCPU pointer
954 *
955 * Suspend execution of a vCPU until a valid wake event is detected, i.e. until
956 * the vCPU is runnable. The vCPU may or may not be scheduled out, depending
957 * on when a wake event arrives, e.g. there may already be a pending wake event.
958 */
kvm_vcpu_wfi(struct kvm_vcpu * vcpu)959 void kvm_vcpu_wfi(struct kvm_vcpu *vcpu)
960 {
961 /*
962 * Sync back the state of the GIC CPU interface so that we have
963 * the latest PMR and group enables. This ensures that
964 * kvm_arch_vcpu_runnable has up-to-date data to decide whether
965 * we have pending interrupts, e.g. when determining if the
966 * vCPU should block.
967 *
968 * For the same reason, we want to tell GICv4 that we need
969 * doorbells to be signalled, should an interrupt become pending.
970 */
971 preempt_disable();
972 vcpu_set_flag(vcpu, IN_WFI);
973 kvm_vgic_put(vcpu);
974 preempt_enable();
975
976 kvm_vcpu_halt(vcpu);
977 vcpu_clear_flag(vcpu, IN_WFIT);
978
979 preempt_disable();
980 vcpu_clear_flag(vcpu, IN_WFI);
981 kvm_vgic_load(vcpu);
982 preempt_enable();
983 }
984
kvm_vcpu_suspend(struct kvm_vcpu * vcpu)985 static int kvm_vcpu_suspend(struct kvm_vcpu *vcpu)
986 {
987 if (!kvm_arm_vcpu_suspended(vcpu))
988 return 1;
989
990 kvm_vcpu_wfi(vcpu);
991
992 /*
993 * The suspend state is sticky; we do not leave it until userspace
994 * explicitly marks the vCPU as runnable. Request that we suspend again
995 * later.
996 */
997 kvm_make_request(KVM_REQ_SUSPEND, vcpu);
998
999 /*
1000 * Check to make sure the vCPU is actually runnable. If so, exit to
1001 * userspace informing it of the wakeup condition.
1002 */
1003 if (kvm_arch_vcpu_runnable(vcpu)) {
1004 memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
1005 vcpu->run->system_event.type = KVM_SYSTEM_EVENT_WAKEUP;
1006 vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
1007 return 0;
1008 }
1009
1010 /*
1011 * Otherwise, we were unblocked to process a different event, such as a
1012 * pending signal. Return 1 and allow kvm_arch_vcpu_ioctl_run() to
1013 * process the event.
1014 */
1015 return 1;
1016 }
1017
1018 /**
1019 * check_vcpu_requests - check and handle pending vCPU requests
1020 * @vcpu: the VCPU pointer
1021 *
1022 * Return: 1 if we should enter the guest
1023 * 0 if we should exit to userspace
1024 * < 0 if we should exit to userspace, where the return value indicates
1025 * an error
1026 */
check_vcpu_requests(struct kvm_vcpu * vcpu)1027 static int check_vcpu_requests(struct kvm_vcpu *vcpu)
1028 {
1029 if (kvm_request_pending(vcpu)) {
1030 if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu))
1031 return -EIO;
1032
1033 if (kvm_check_request(KVM_REQ_SLEEP, vcpu))
1034 kvm_vcpu_sleep(vcpu);
1035
1036 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1037 kvm_reset_vcpu(vcpu);
1038
1039 /*
1040 * Clear IRQ_PENDING requests that were made to guarantee
1041 * that a VCPU sees new virtual interrupts.
1042 */
1043 kvm_check_request(KVM_REQ_IRQ_PENDING, vcpu);
1044
1045 if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
1046 kvm_update_stolen_time(vcpu);
1047
1048 if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
1049 /* The distributor enable bits were changed */
1050 preempt_disable();
1051 vgic_v4_put(vcpu);
1052 vgic_v4_load(vcpu);
1053 preempt_enable();
1054 }
1055
1056 if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu))
1057 kvm_vcpu_reload_pmu(vcpu);
1058
1059 if (kvm_check_request(KVM_REQ_RESYNC_PMU_EL0, vcpu))
1060 kvm_vcpu_pmu_restore_guest(vcpu);
1061
1062 if (kvm_check_request(KVM_REQ_SUSPEND, vcpu))
1063 return kvm_vcpu_suspend(vcpu);
1064
1065 if (kvm_dirty_ring_check_request(vcpu))
1066 return 0;
1067
1068 check_nested_vcpu_requests(vcpu);
1069 }
1070
1071 return 1;
1072 }
1073
vcpu_mode_is_bad_32bit(struct kvm_vcpu * vcpu)1074 static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu)
1075 {
1076 if (likely(!vcpu_mode_is_32bit(vcpu)))
1077 return false;
1078
1079 if (vcpu_has_nv(vcpu))
1080 return true;
1081
1082 return !kvm_supports_32bit_el0();
1083 }
1084
1085 /**
1086 * kvm_vcpu_exit_request - returns true if the VCPU should *not* enter the guest
1087 * @vcpu: The VCPU pointer
1088 * @ret: Pointer to write optional return code
1089 *
1090 * Returns: true if the VCPU needs to return to a preemptible + interruptible
1091 * and skip guest entry.
1092 *
1093 * This function disambiguates between two different types of exits: exits to a
1094 * preemptible + interruptible kernel context and exits to userspace. For an
1095 * exit to userspace, this function will write the return code to ret and return
1096 * true. For an exit to preemptible + interruptible kernel context (i.e. check
1097 * for pending work and re-enter), return true without writing to ret.
1098 */
kvm_vcpu_exit_request(struct kvm_vcpu * vcpu,int * ret)1099 static bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu, int *ret)
1100 {
1101 struct kvm_run *run = vcpu->run;
1102
1103 /*
1104 * If we're using a userspace irqchip, then check if we need
1105 * to tell a userspace irqchip about timer or PMU level
1106 * changes and if so, exit to userspace (the actual level
1107 * state gets updated in kvm_timer_update_run and
1108 * kvm_pmu_update_run below).
1109 */
1110 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1111 if (kvm_timer_should_notify_user(vcpu) ||
1112 kvm_pmu_should_notify_user(vcpu)) {
1113 *ret = -EINTR;
1114 run->exit_reason = KVM_EXIT_INTR;
1115 return true;
1116 }
1117 }
1118
1119 if (unlikely(vcpu_on_unsupported_cpu(vcpu))) {
1120 run->exit_reason = KVM_EXIT_FAIL_ENTRY;
1121 run->fail_entry.hardware_entry_failure_reason = KVM_EXIT_FAIL_ENTRY_CPU_UNSUPPORTED;
1122 run->fail_entry.cpu = smp_processor_id();
1123 *ret = 0;
1124 return true;
1125 }
1126
1127 return kvm_request_pending(vcpu) ||
1128 xfer_to_guest_mode_work_pending();
1129 }
1130
1131 /*
1132 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
1133 * the vCPU is running.
1134 *
1135 * This must be noinstr as instrumentation may make use of RCU, and this is not
1136 * safe during the EQS.
1137 */
kvm_arm_vcpu_enter_exit(struct kvm_vcpu * vcpu)1138 static int noinstr kvm_arm_vcpu_enter_exit(struct kvm_vcpu *vcpu)
1139 {
1140 int ret;
1141
1142 guest_state_enter_irqoff();
1143 ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
1144 guest_state_exit_irqoff();
1145
1146 return ret;
1147 }
1148
1149 /**
1150 * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
1151 * @vcpu: The VCPU pointer
1152 *
1153 * This function is called through the VCPU_RUN ioctl called from user space. It
1154 * will execute VM code in a loop until the time slice for the process is used
1155 * or some emulation is needed from user space in which case the function will
1156 * return with return value 0 and with the kvm_run structure filled in with the
1157 * required data for the requested emulation.
1158 */
kvm_arch_vcpu_ioctl_run(struct kvm_vcpu * vcpu)1159 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
1160 {
1161 struct kvm_run *run = vcpu->run;
1162 int ret;
1163
1164 if (run->exit_reason == KVM_EXIT_MMIO) {
1165 ret = kvm_handle_mmio_return(vcpu);
1166 if (ret <= 0)
1167 return ret;
1168 }
1169
1170 vcpu_load(vcpu);
1171
1172 if (!vcpu->wants_to_run) {
1173 ret = -EINTR;
1174 goto out;
1175 }
1176
1177 kvm_sigset_activate(vcpu);
1178
1179 ret = 1;
1180 run->exit_reason = KVM_EXIT_UNKNOWN;
1181 run->flags = 0;
1182 while (ret > 0) {
1183 /*
1184 * Check conditions before entering the guest
1185 */
1186 ret = kvm_xfer_to_guest_mode_handle_work(vcpu);
1187 if (!ret)
1188 ret = 1;
1189
1190 if (ret > 0)
1191 ret = check_vcpu_requests(vcpu);
1192
1193 /*
1194 * Preparing the interrupts to be injected also
1195 * involves poking the GIC, which must be done in a
1196 * non-preemptible context.
1197 */
1198 preempt_disable();
1199
1200 kvm_nested_flush_hwstate(vcpu);
1201
1202 if (kvm_vcpu_has_pmu(vcpu))
1203 kvm_pmu_flush_hwstate(vcpu);
1204
1205 local_irq_disable();
1206
1207 kvm_vgic_flush_hwstate(vcpu);
1208
1209 kvm_pmu_update_vcpu_events(vcpu);
1210
1211 /*
1212 * Ensure we set mode to IN_GUEST_MODE after we disable
1213 * interrupts and before the final VCPU requests check.
1214 * See the comment in kvm_vcpu_exiting_guest_mode() and
1215 * Documentation/virt/kvm/vcpu-requests.rst
1216 */
1217 smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1218
1219 if (ret <= 0 || kvm_vcpu_exit_request(vcpu, &ret)) {
1220 vcpu->mode = OUTSIDE_GUEST_MODE;
1221 isb(); /* Ensure work in x_flush_hwstate is committed */
1222 if (kvm_vcpu_has_pmu(vcpu))
1223 kvm_pmu_sync_hwstate(vcpu);
1224 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1225 kvm_timer_sync_user(vcpu);
1226 kvm_vgic_sync_hwstate(vcpu);
1227 local_irq_enable();
1228 preempt_enable();
1229 continue;
1230 }
1231
1232 kvm_arch_vcpu_ctxflush_fp(vcpu);
1233
1234 /**************************************************************
1235 * Enter the guest
1236 */
1237 trace_kvm_entry(*vcpu_pc(vcpu));
1238 guest_timing_enter_irqoff();
1239
1240 ret = kvm_arm_vcpu_enter_exit(vcpu);
1241
1242 vcpu->mode = OUTSIDE_GUEST_MODE;
1243 vcpu->stat.exits++;
1244 /*
1245 * Back from guest
1246 *************************************************************/
1247
1248 /*
1249 * We must sync the PMU state before the vgic state so
1250 * that the vgic can properly sample the updated state of the
1251 * interrupt line.
1252 */
1253 if (kvm_vcpu_has_pmu(vcpu))
1254 kvm_pmu_sync_hwstate(vcpu);
1255
1256 /*
1257 * Sync the vgic state before syncing the timer state because
1258 * the timer code needs to know if the virtual timer
1259 * interrupts are active.
1260 */
1261 kvm_vgic_sync_hwstate(vcpu);
1262
1263 /*
1264 * Sync the timer hardware state before enabling interrupts as
1265 * we don't want vtimer interrupts to race with syncing the
1266 * timer virtual interrupt state.
1267 */
1268 if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
1269 kvm_timer_sync_user(vcpu);
1270
1271 if (is_hyp_ctxt(vcpu))
1272 kvm_timer_sync_nested(vcpu);
1273
1274 kvm_arch_vcpu_ctxsync_fp(vcpu);
1275
1276 /*
1277 * We must ensure that any pending interrupts are taken before
1278 * we exit guest timing so that timer ticks are accounted as
1279 * guest time. Transiently unmask interrupts so that any
1280 * pending interrupts are taken.
1281 *
1282 * Per ARM DDI 0487G.b section D1.13.4, an ISB (or other
1283 * context synchronization event) is necessary to ensure that
1284 * pending interrupts are taken.
1285 */
1286 if (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_IRQ) {
1287 local_irq_enable();
1288 isb();
1289 local_irq_disable();
1290 }
1291
1292 guest_timing_exit_irqoff();
1293
1294 local_irq_enable();
1295
1296 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
1297
1298 /* Exit types that need handling before we can be preempted */
1299 handle_exit_early(vcpu, ret);
1300
1301 kvm_nested_sync_hwstate(vcpu);
1302
1303 preempt_enable();
1304
1305 /*
1306 * The ARMv8 architecture doesn't give the hypervisor
1307 * a mechanism to prevent a guest from dropping to AArch32 EL0
1308 * if implemented by the CPU. If we spot the guest in such
1309 * state and that we decided it wasn't supposed to do so (like
1310 * with the asymmetric AArch32 case), return to userspace with
1311 * a fatal error.
1312 */
1313 if (vcpu_mode_is_bad_32bit(vcpu)) {
1314 /*
1315 * As we have caught the guest red-handed, decide that
1316 * it isn't fit for purpose anymore by making the vcpu
1317 * invalid. The VMM can try and fix it by issuing a
1318 * KVM_ARM_VCPU_INIT if it really wants to.
1319 */
1320 vcpu_clear_flag(vcpu, VCPU_INITIALIZED);
1321 ret = ARM_EXCEPTION_IL;
1322 }
1323
1324 ret = handle_exit(vcpu, ret);
1325 }
1326
1327 /* Tell userspace about in-kernel device output levels */
1328 if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
1329 kvm_timer_update_run(vcpu);
1330 kvm_pmu_update_run(vcpu);
1331 }
1332
1333 kvm_sigset_deactivate(vcpu);
1334
1335 out:
1336 /*
1337 * In the unlikely event that we are returning to userspace
1338 * with pending exceptions or PC adjustment, commit these
1339 * adjustments in order to give userspace a consistent view of
1340 * the vcpu state. Note that this relies on __kvm_adjust_pc()
1341 * being preempt-safe on VHE.
1342 */
1343 if (unlikely(vcpu_get_flag(vcpu, PENDING_EXCEPTION) ||
1344 vcpu_get_flag(vcpu, INCREMENT_PC)))
1345 kvm_call_hyp(__kvm_adjust_pc, vcpu);
1346
1347 vcpu_put(vcpu);
1348 return ret;
1349 }
1350
vcpu_interrupt_line(struct kvm_vcpu * vcpu,int number,bool level)1351 static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
1352 {
1353 int bit_index;
1354 bool set;
1355 unsigned long *hcr;
1356
1357 if (number == KVM_ARM_IRQ_CPU_IRQ)
1358 bit_index = __ffs(HCR_VI);
1359 else /* KVM_ARM_IRQ_CPU_FIQ */
1360 bit_index = __ffs(HCR_VF);
1361
1362 hcr = vcpu_hcr(vcpu);
1363 if (level)
1364 set = test_and_set_bit(bit_index, hcr);
1365 else
1366 set = test_and_clear_bit(bit_index, hcr);
1367
1368 /*
1369 * If we didn't change anything, no need to wake up or kick other CPUs
1370 */
1371 if (set == level)
1372 return 0;
1373
1374 /*
1375 * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
1376 * trigger a world-switch round on the running physical CPU to set the
1377 * virtual IRQ/FIQ fields in the HCR appropriately.
1378 */
1379 kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
1380 kvm_vcpu_kick(vcpu);
1381
1382 return 0;
1383 }
1384
kvm_vm_ioctl_irq_line(struct kvm * kvm,struct kvm_irq_level * irq_level,bool line_status)1385 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
1386 bool line_status)
1387 {
1388 u32 irq = irq_level->irq;
1389 unsigned int irq_type, vcpu_id, irq_num;
1390 struct kvm_vcpu *vcpu = NULL;
1391 bool level = irq_level->level;
1392
1393 irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
1394 vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
1395 vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
1396 irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
1397
1398 trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
1399
1400 switch (irq_type) {
1401 case KVM_ARM_IRQ_TYPE_CPU:
1402 if (irqchip_in_kernel(kvm))
1403 return -ENXIO;
1404
1405 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1406 if (!vcpu)
1407 return -EINVAL;
1408
1409 if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
1410 return -EINVAL;
1411
1412 return vcpu_interrupt_line(vcpu, irq_num, level);
1413 case KVM_ARM_IRQ_TYPE_PPI:
1414 if (!irqchip_in_kernel(kvm))
1415 return -ENXIO;
1416
1417 vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
1418 if (!vcpu)
1419 return -EINVAL;
1420
1421 if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
1422 return -EINVAL;
1423
1424 return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
1425 case KVM_ARM_IRQ_TYPE_SPI:
1426 if (!irqchip_in_kernel(kvm))
1427 return -ENXIO;
1428
1429 if (irq_num < VGIC_NR_PRIVATE_IRQS)
1430 return -EINVAL;
1431
1432 return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
1433 }
1434
1435 return -EINVAL;
1436 }
1437
system_supported_vcpu_features(void)1438 static unsigned long system_supported_vcpu_features(void)
1439 {
1440 unsigned long features = KVM_VCPU_VALID_FEATURES;
1441
1442 if (!cpus_have_final_cap(ARM64_HAS_32BIT_EL1))
1443 clear_bit(KVM_ARM_VCPU_EL1_32BIT, &features);
1444
1445 if (!kvm_supports_guest_pmuv3())
1446 clear_bit(KVM_ARM_VCPU_PMU_V3, &features);
1447
1448 if (!system_supports_sve())
1449 clear_bit(KVM_ARM_VCPU_SVE, &features);
1450
1451 if (!kvm_has_full_ptr_auth()) {
1452 clear_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features);
1453 clear_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features);
1454 }
1455
1456 if (!cpus_have_final_cap(ARM64_HAS_NESTED_VIRT))
1457 clear_bit(KVM_ARM_VCPU_HAS_EL2, &features);
1458
1459 return features;
1460 }
1461
kvm_vcpu_init_check_features(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1462 static int kvm_vcpu_init_check_features(struct kvm_vcpu *vcpu,
1463 const struct kvm_vcpu_init *init)
1464 {
1465 unsigned long features = init->features[0];
1466 int i;
1467
1468 if (features & ~KVM_VCPU_VALID_FEATURES)
1469 return -ENOENT;
1470
1471 for (i = 1; i < ARRAY_SIZE(init->features); i++) {
1472 if (init->features[i])
1473 return -ENOENT;
1474 }
1475
1476 if (features & ~system_supported_vcpu_features())
1477 return -EINVAL;
1478
1479 /*
1480 * For now make sure that both address/generic pointer authentication
1481 * features are requested by the userspace together.
1482 */
1483 if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, &features) !=
1484 test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, &features))
1485 return -EINVAL;
1486
1487 if (!test_bit(KVM_ARM_VCPU_EL1_32BIT, &features))
1488 return 0;
1489
1490 /* MTE is incompatible with AArch32 */
1491 if (kvm_has_mte(vcpu->kvm))
1492 return -EINVAL;
1493
1494 /* NV is incompatible with AArch32 */
1495 if (test_bit(KVM_ARM_VCPU_HAS_EL2, &features))
1496 return -EINVAL;
1497
1498 return 0;
1499 }
1500
kvm_vcpu_init_changed(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1501 static bool kvm_vcpu_init_changed(struct kvm_vcpu *vcpu,
1502 const struct kvm_vcpu_init *init)
1503 {
1504 unsigned long features = init->features[0];
1505
1506 return !bitmap_equal(vcpu->kvm->arch.vcpu_features, &features,
1507 KVM_VCPU_MAX_FEATURES);
1508 }
1509
kvm_setup_vcpu(struct kvm_vcpu * vcpu)1510 static int kvm_setup_vcpu(struct kvm_vcpu *vcpu)
1511 {
1512 struct kvm *kvm = vcpu->kvm;
1513 int ret = 0;
1514
1515 /*
1516 * When the vCPU has a PMU, but no PMU is set for the guest
1517 * yet, set the default one.
1518 */
1519 if (kvm_vcpu_has_pmu(vcpu) && !kvm->arch.arm_pmu)
1520 ret = kvm_arm_set_default_pmu(kvm);
1521
1522 /* Prepare for nested if required */
1523 if (!ret && vcpu_has_nv(vcpu))
1524 ret = kvm_vcpu_init_nested(vcpu);
1525
1526 return ret;
1527 }
1528
__kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1529 static int __kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1530 const struct kvm_vcpu_init *init)
1531 {
1532 unsigned long features = init->features[0];
1533 struct kvm *kvm = vcpu->kvm;
1534 int ret = -EINVAL;
1535
1536 mutex_lock(&kvm->arch.config_lock);
1537
1538 if (test_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags) &&
1539 kvm_vcpu_init_changed(vcpu, init))
1540 goto out_unlock;
1541
1542 bitmap_copy(kvm->arch.vcpu_features, &features, KVM_VCPU_MAX_FEATURES);
1543
1544 ret = kvm_setup_vcpu(vcpu);
1545 if (ret)
1546 goto out_unlock;
1547
1548 /* Now we know what it is, we can reset it. */
1549 kvm_reset_vcpu(vcpu);
1550
1551 set_bit(KVM_ARCH_FLAG_VCPU_FEATURES_CONFIGURED, &kvm->arch.flags);
1552 vcpu_set_flag(vcpu, VCPU_INITIALIZED);
1553 ret = 0;
1554 out_unlock:
1555 mutex_unlock(&kvm->arch.config_lock);
1556 return ret;
1557 }
1558
kvm_vcpu_set_target(struct kvm_vcpu * vcpu,const struct kvm_vcpu_init * init)1559 static int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
1560 const struct kvm_vcpu_init *init)
1561 {
1562 int ret;
1563
1564 if (init->target != KVM_ARM_TARGET_GENERIC_V8 &&
1565 init->target != kvm_target_cpu())
1566 return -EINVAL;
1567
1568 ret = kvm_vcpu_init_check_features(vcpu, init);
1569 if (ret)
1570 return ret;
1571
1572 if (!kvm_vcpu_initialized(vcpu))
1573 return __kvm_vcpu_set_target(vcpu, init);
1574
1575 if (kvm_vcpu_init_changed(vcpu, init))
1576 return -EINVAL;
1577
1578 kvm_reset_vcpu(vcpu);
1579 return 0;
1580 }
1581
kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu * vcpu,struct kvm_vcpu_init * init)1582 static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
1583 struct kvm_vcpu_init *init)
1584 {
1585 bool power_off = false;
1586 int ret;
1587
1588 /*
1589 * Treat the power-off vCPU feature as ephemeral. Clear the bit to avoid
1590 * reflecting it in the finalized feature set, thus limiting its scope
1591 * to a single KVM_ARM_VCPU_INIT call.
1592 */
1593 if (init->features[0] & BIT(KVM_ARM_VCPU_POWER_OFF)) {
1594 init->features[0] &= ~BIT(KVM_ARM_VCPU_POWER_OFF);
1595 power_off = true;
1596 }
1597
1598 ret = kvm_vcpu_set_target(vcpu, init);
1599 if (ret)
1600 return ret;
1601
1602 /*
1603 * Ensure a rebooted VM will fault in RAM pages and detect if the
1604 * guest MMU is turned off and flush the caches as needed.
1605 *
1606 * S2FWB enforces all memory accesses to RAM being cacheable,
1607 * ensuring that the data side is always coherent. We still
1608 * need to invalidate the I-cache though, as FWB does *not*
1609 * imply CTR_EL0.DIC.
1610 */
1611 if (vcpu_has_run_once(vcpu)) {
1612 if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB))
1613 stage2_unmap_vm(vcpu->kvm);
1614 else
1615 icache_inval_all_pou();
1616 }
1617
1618 vcpu_reset_hcr(vcpu);
1619
1620 /*
1621 * Handle the "start in power-off" case.
1622 */
1623 spin_lock(&vcpu->arch.mp_state_lock);
1624
1625 if (power_off)
1626 __kvm_arm_vcpu_power_off(vcpu);
1627 else
1628 WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE);
1629
1630 spin_unlock(&vcpu->arch.mp_state_lock);
1631
1632 return 0;
1633 }
1634
kvm_arm_vcpu_set_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1635 static int kvm_arm_vcpu_set_attr(struct kvm_vcpu *vcpu,
1636 struct kvm_device_attr *attr)
1637 {
1638 int ret = -ENXIO;
1639
1640 switch (attr->group) {
1641 default:
1642 ret = kvm_arm_vcpu_arch_set_attr(vcpu, attr);
1643 break;
1644 }
1645
1646 return ret;
1647 }
1648
kvm_arm_vcpu_get_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1649 static int kvm_arm_vcpu_get_attr(struct kvm_vcpu *vcpu,
1650 struct kvm_device_attr *attr)
1651 {
1652 int ret = -ENXIO;
1653
1654 switch (attr->group) {
1655 default:
1656 ret = kvm_arm_vcpu_arch_get_attr(vcpu, attr);
1657 break;
1658 }
1659
1660 return ret;
1661 }
1662
kvm_arm_vcpu_has_attr(struct kvm_vcpu * vcpu,struct kvm_device_attr * attr)1663 static int kvm_arm_vcpu_has_attr(struct kvm_vcpu *vcpu,
1664 struct kvm_device_attr *attr)
1665 {
1666 int ret = -ENXIO;
1667
1668 switch (attr->group) {
1669 default:
1670 ret = kvm_arm_vcpu_arch_has_attr(vcpu, attr);
1671 break;
1672 }
1673
1674 return ret;
1675 }
1676
kvm_arm_vcpu_get_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1677 static int kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
1678 struct kvm_vcpu_events *events)
1679 {
1680 memset(events, 0, sizeof(*events));
1681
1682 return __kvm_arm_vcpu_get_events(vcpu, events);
1683 }
1684
kvm_arm_vcpu_set_events(struct kvm_vcpu * vcpu,struct kvm_vcpu_events * events)1685 static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
1686 struct kvm_vcpu_events *events)
1687 {
1688 int i;
1689
1690 /* check whether the reserved field is zero */
1691 for (i = 0; i < ARRAY_SIZE(events->reserved); i++)
1692 if (events->reserved[i])
1693 return -EINVAL;
1694
1695 /* check whether the pad field is zero */
1696 for (i = 0; i < ARRAY_SIZE(events->exception.pad); i++)
1697 if (events->exception.pad[i])
1698 return -EINVAL;
1699
1700 return __kvm_arm_vcpu_set_events(vcpu, events);
1701 }
1702
kvm_arch_vcpu_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1703 long kvm_arch_vcpu_ioctl(struct file *filp,
1704 unsigned int ioctl, unsigned long arg)
1705 {
1706 struct kvm_vcpu *vcpu = filp->private_data;
1707 void __user *argp = (void __user *)arg;
1708 struct kvm_device_attr attr;
1709 long r;
1710
1711 switch (ioctl) {
1712 case KVM_ARM_VCPU_INIT: {
1713 struct kvm_vcpu_init init;
1714
1715 r = -EFAULT;
1716 if (copy_from_user(&init, argp, sizeof(init)))
1717 break;
1718
1719 r = kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init);
1720 break;
1721 }
1722 case KVM_SET_ONE_REG:
1723 case KVM_GET_ONE_REG: {
1724 struct kvm_one_reg reg;
1725
1726 r = -ENOEXEC;
1727 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1728 break;
1729
1730 r = -EFAULT;
1731 if (copy_from_user(®, argp, sizeof(reg)))
1732 break;
1733
1734 /*
1735 * We could owe a reset due to PSCI. Handle the pending reset
1736 * here to ensure userspace register accesses are ordered after
1737 * the reset.
1738 */
1739 if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
1740 kvm_reset_vcpu(vcpu);
1741
1742 if (ioctl == KVM_SET_ONE_REG)
1743 r = kvm_arm_set_reg(vcpu, ®);
1744 else
1745 r = kvm_arm_get_reg(vcpu, ®);
1746 break;
1747 }
1748 case KVM_GET_REG_LIST: {
1749 struct kvm_reg_list __user *user_list = argp;
1750 struct kvm_reg_list reg_list;
1751 unsigned n;
1752
1753 r = -ENOEXEC;
1754 if (unlikely(!kvm_vcpu_initialized(vcpu)))
1755 break;
1756
1757 r = -EPERM;
1758 if (!kvm_arm_vcpu_is_finalized(vcpu))
1759 break;
1760
1761 r = -EFAULT;
1762 if (copy_from_user(®_list, user_list, sizeof(reg_list)))
1763 break;
1764 n = reg_list.n;
1765 reg_list.n = kvm_arm_num_regs(vcpu);
1766 if (copy_to_user(user_list, ®_list, sizeof(reg_list)))
1767 break;
1768 r = -E2BIG;
1769 if (n < reg_list.n)
1770 break;
1771 r = kvm_arm_copy_reg_indices(vcpu, user_list->reg);
1772 break;
1773 }
1774 case KVM_SET_DEVICE_ATTR: {
1775 r = -EFAULT;
1776 if (copy_from_user(&attr, argp, sizeof(attr)))
1777 break;
1778 r = kvm_arm_vcpu_set_attr(vcpu, &attr);
1779 break;
1780 }
1781 case KVM_GET_DEVICE_ATTR: {
1782 r = -EFAULT;
1783 if (copy_from_user(&attr, argp, sizeof(attr)))
1784 break;
1785 r = kvm_arm_vcpu_get_attr(vcpu, &attr);
1786 break;
1787 }
1788 case KVM_HAS_DEVICE_ATTR: {
1789 r = -EFAULT;
1790 if (copy_from_user(&attr, argp, sizeof(attr)))
1791 break;
1792 r = kvm_arm_vcpu_has_attr(vcpu, &attr);
1793 break;
1794 }
1795 case KVM_GET_VCPU_EVENTS: {
1796 struct kvm_vcpu_events events;
1797
1798 if (!kvm_vcpu_initialized(vcpu))
1799 return -ENOEXEC;
1800
1801 if (kvm_arm_vcpu_get_events(vcpu, &events))
1802 return -EINVAL;
1803
1804 if (copy_to_user(argp, &events, sizeof(events)))
1805 return -EFAULT;
1806
1807 return 0;
1808 }
1809 case KVM_SET_VCPU_EVENTS: {
1810 struct kvm_vcpu_events events;
1811
1812 if (!kvm_vcpu_initialized(vcpu))
1813 return -ENOEXEC;
1814
1815 if (copy_from_user(&events, argp, sizeof(events)))
1816 return -EFAULT;
1817
1818 return kvm_arm_vcpu_set_events(vcpu, &events);
1819 }
1820 case KVM_ARM_VCPU_FINALIZE: {
1821 int what;
1822
1823 if (!kvm_vcpu_initialized(vcpu))
1824 return -ENOEXEC;
1825
1826 if (get_user(what, (const int __user *)argp))
1827 return -EFAULT;
1828
1829 return kvm_arm_vcpu_finalize(vcpu, what);
1830 }
1831 default:
1832 r = -EINVAL;
1833 }
1834
1835 return r;
1836 }
1837
kvm_arch_sync_dirty_log(struct kvm * kvm,struct kvm_memory_slot * memslot)1838 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
1839 {
1840
1841 }
1842
kvm_vm_ioctl_set_device_addr(struct kvm * kvm,struct kvm_arm_device_addr * dev_addr)1843 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
1844 struct kvm_arm_device_addr *dev_addr)
1845 {
1846 switch (FIELD_GET(KVM_ARM_DEVICE_ID_MASK, dev_addr->id)) {
1847 case KVM_ARM_DEVICE_VGIC_V2:
1848 if (!vgic_present)
1849 return -ENXIO;
1850 return kvm_set_legacy_vgic_v2_addr(kvm, dev_addr);
1851 default:
1852 return -ENODEV;
1853 }
1854 }
1855
kvm_vm_has_attr(struct kvm * kvm,struct kvm_device_attr * attr)1856 static int kvm_vm_has_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1857 {
1858 switch (attr->group) {
1859 case KVM_ARM_VM_SMCCC_CTRL:
1860 return kvm_vm_smccc_has_attr(kvm, attr);
1861 default:
1862 return -ENXIO;
1863 }
1864 }
1865
kvm_vm_set_attr(struct kvm * kvm,struct kvm_device_attr * attr)1866 static int kvm_vm_set_attr(struct kvm *kvm, struct kvm_device_attr *attr)
1867 {
1868 switch (attr->group) {
1869 case KVM_ARM_VM_SMCCC_CTRL:
1870 return kvm_vm_smccc_set_attr(kvm, attr);
1871 default:
1872 return -ENXIO;
1873 }
1874 }
1875
kvm_arch_vm_ioctl(struct file * filp,unsigned int ioctl,unsigned long arg)1876 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1877 {
1878 struct kvm *kvm = filp->private_data;
1879 void __user *argp = (void __user *)arg;
1880 struct kvm_device_attr attr;
1881
1882 switch (ioctl) {
1883 case KVM_CREATE_IRQCHIP: {
1884 int ret;
1885 if (!vgic_present)
1886 return -ENXIO;
1887 mutex_lock(&kvm->lock);
1888 ret = kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
1889 mutex_unlock(&kvm->lock);
1890 return ret;
1891 }
1892 case KVM_ARM_SET_DEVICE_ADDR: {
1893 struct kvm_arm_device_addr dev_addr;
1894
1895 if (copy_from_user(&dev_addr, argp, sizeof(dev_addr)))
1896 return -EFAULT;
1897 return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr);
1898 }
1899 case KVM_ARM_PREFERRED_TARGET: {
1900 struct kvm_vcpu_init init = {
1901 .target = KVM_ARM_TARGET_GENERIC_V8,
1902 };
1903
1904 if (copy_to_user(argp, &init, sizeof(init)))
1905 return -EFAULT;
1906
1907 return 0;
1908 }
1909 case KVM_ARM_MTE_COPY_TAGS: {
1910 struct kvm_arm_copy_mte_tags copy_tags;
1911
1912 if (copy_from_user(©_tags, argp, sizeof(copy_tags)))
1913 return -EFAULT;
1914 return kvm_vm_ioctl_mte_copy_tags(kvm, ©_tags);
1915 }
1916 case KVM_ARM_SET_COUNTER_OFFSET: {
1917 struct kvm_arm_counter_offset offset;
1918
1919 if (copy_from_user(&offset, argp, sizeof(offset)))
1920 return -EFAULT;
1921 return kvm_vm_ioctl_set_counter_offset(kvm, &offset);
1922 }
1923 case KVM_HAS_DEVICE_ATTR: {
1924 if (copy_from_user(&attr, argp, sizeof(attr)))
1925 return -EFAULT;
1926
1927 return kvm_vm_has_attr(kvm, &attr);
1928 }
1929 case KVM_SET_DEVICE_ATTR: {
1930 if (copy_from_user(&attr, argp, sizeof(attr)))
1931 return -EFAULT;
1932
1933 return kvm_vm_set_attr(kvm, &attr);
1934 }
1935 case KVM_ARM_GET_REG_WRITABLE_MASKS: {
1936 struct reg_mask_range range;
1937
1938 if (copy_from_user(&range, argp, sizeof(range)))
1939 return -EFAULT;
1940 return kvm_vm_ioctl_get_reg_writable_masks(kvm, &range);
1941 }
1942 default:
1943 return -EINVAL;
1944 }
1945 }
1946
nvhe_percpu_size(void)1947 static unsigned long nvhe_percpu_size(void)
1948 {
1949 return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) -
1950 (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start);
1951 }
1952
nvhe_percpu_order(void)1953 static unsigned long nvhe_percpu_order(void)
1954 {
1955 unsigned long size = nvhe_percpu_size();
1956
1957 return size ? get_order(size) : 0;
1958 }
1959
pkvm_host_sve_state_order(void)1960 static size_t pkvm_host_sve_state_order(void)
1961 {
1962 return get_order(pkvm_host_sve_state_size());
1963 }
1964
1965 /* A lookup table holding the hypervisor VA for each vector slot */
1966 static void *hyp_spectre_vector_selector[BP_HARDEN_EL2_SLOTS];
1967
kvm_init_vector_slot(void * base,enum arm64_hyp_spectre_vector slot)1968 static void kvm_init_vector_slot(void *base, enum arm64_hyp_spectre_vector slot)
1969 {
1970 hyp_spectre_vector_selector[slot] = __kvm_vector_slot2addr(base, slot);
1971 }
1972
kvm_init_vector_slots(void)1973 static int kvm_init_vector_slots(void)
1974 {
1975 int err;
1976 void *base;
1977
1978 base = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
1979 kvm_init_vector_slot(base, HYP_VECTOR_DIRECT);
1980
1981 base = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
1982 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_DIRECT);
1983
1984 if (kvm_system_needs_idmapped_vectors() &&
1985 !is_protected_kvm_enabled()) {
1986 err = create_hyp_exec_mappings(__pa_symbol(__bp_harden_hyp_vecs),
1987 __BP_HARDEN_HYP_VECS_SZ, &base);
1988 if (err)
1989 return err;
1990 }
1991
1992 kvm_init_vector_slot(base, HYP_VECTOR_INDIRECT);
1993 kvm_init_vector_slot(base, HYP_VECTOR_SPECTRE_INDIRECT);
1994 return 0;
1995 }
1996
cpu_prepare_hyp_mode(int cpu,u32 hyp_va_bits)1997 static void __init cpu_prepare_hyp_mode(int cpu, u32 hyp_va_bits)
1998 {
1999 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2000 unsigned long tcr;
2001
2002 /*
2003 * Calculate the raw per-cpu offset without a translation from the
2004 * kernel's mapping to the linear mapping, and store it in tpidr_el2
2005 * so that we can use adr_l to access per-cpu variables in EL2.
2006 * Also drop the KASAN tag which gets in the way...
2007 */
2008 params->tpidr_el2 = (unsigned long)kasan_reset_tag(per_cpu_ptr_nvhe_sym(__per_cpu_start, cpu)) -
2009 (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start));
2010
2011 params->mair_el2 = read_sysreg(mair_el1);
2012
2013 tcr = read_sysreg(tcr_el1);
2014 if (cpus_have_final_cap(ARM64_KVM_HVHE)) {
2015 tcr &= ~(TCR_HD | TCR_HA | TCR_A1 | TCR_T0SZ_MASK);
2016 tcr |= TCR_EPD1_MASK;
2017 } else {
2018 unsigned long ips = FIELD_GET(TCR_IPS_MASK, tcr);
2019
2020 tcr &= TCR_EL2_MASK;
2021 tcr |= TCR_EL2_RES1 | FIELD_PREP(TCR_EL2_PS_MASK, ips);
2022 if (lpa2_is_enabled())
2023 tcr |= TCR_EL2_DS;
2024 }
2025 tcr |= TCR_T0SZ(hyp_va_bits);
2026 params->tcr_el2 = tcr;
2027
2028 params->pgd_pa = kvm_mmu_get_httbr();
2029 if (is_protected_kvm_enabled())
2030 params->hcr_el2 = HCR_HOST_NVHE_PROTECTED_FLAGS;
2031 else
2032 params->hcr_el2 = HCR_HOST_NVHE_FLAGS;
2033 if (cpus_have_final_cap(ARM64_KVM_HVHE))
2034 params->hcr_el2 |= HCR_E2H;
2035 params->vttbr = params->vtcr = 0;
2036
2037 /*
2038 * Flush the init params from the data cache because the struct will
2039 * be read while the MMU is off.
2040 */
2041 kvm_flush_dcache_to_poc(params, sizeof(*params));
2042 }
2043
hyp_install_host_vector(void)2044 static void hyp_install_host_vector(void)
2045 {
2046 struct kvm_nvhe_init_params *params;
2047 struct arm_smccc_res res;
2048
2049 /* Switch from the HYP stub to our own HYP init vector */
2050 __hyp_set_vectors(kvm_get_idmap_vector());
2051
2052 /*
2053 * Call initialization code, and switch to the full blown HYP code.
2054 * If the cpucaps haven't been finalized yet, something has gone very
2055 * wrong, and hyp will crash and burn when it uses any
2056 * cpus_have_*_cap() wrapper.
2057 */
2058 BUG_ON(!system_capabilities_finalized());
2059 params = this_cpu_ptr_nvhe_sym(kvm_init_params);
2060 arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), virt_to_phys(params), &res);
2061 WARN_ON(res.a0 != SMCCC_RET_SUCCESS);
2062 }
2063
cpu_init_hyp_mode(void)2064 static void cpu_init_hyp_mode(void)
2065 {
2066 hyp_install_host_vector();
2067
2068 /*
2069 * Disabling SSBD on a non-VHE system requires us to enable SSBS
2070 * at EL2.
2071 */
2072 if (this_cpu_has_cap(ARM64_SSBS) &&
2073 arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) {
2074 kvm_call_hyp_nvhe(__kvm_enable_ssbs);
2075 }
2076 }
2077
cpu_hyp_reset(void)2078 static void cpu_hyp_reset(void)
2079 {
2080 if (!is_kernel_in_hyp_mode())
2081 __hyp_reset_vectors();
2082 }
2083
2084 /*
2085 * EL2 vectors can be mapped and rerouted in a number of ways,
2086 * depending on the kernel configuration and CPU present:
2087 *
2088 * - If the CPU is affected by Spectre-v2, the hardening sequence is
2089 * placed in one of the vector slots, which is executed before jumping
2090 * to the real vectors.
2091 *
2092 * - If the CPU also has the ARM64_SPECTRE_V3A cap, the slot
2093 * containing the hardening sequence is mapped next to the idmap page,
2094 * and executed before jumping to the real vectors.
2095 *
2096 * - If the CPU only has the ARM64_SPECTRE_V3A cap, then an
2097 * empty slot is selected, mapped next to the idmap page, and
2098 * executed before jumping to the real vectors.
2099 *
2100 * Note that ARM64_SPECTRE_V3A is somewhat incompatible with
2101 * VHE, as we don't have hypervisor-specific mappings. If the system
2102 * is VHE and yet selects this capability, it will be ignored.
2103 */
cpu_set_hyp_vector(void)2104 static void cpu_set_hyp_vector(void)
2105 {
2106 struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data);
2107 void *vector = hyp_spectre_vector_selector[data->slot];
2108
2109 if (!is_protected_kvm_enabled())
2110 *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)vector;
2111 else
2112 kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot);
2113 }
2114
cpu_hyp_init_context(void)2115 static void cpu_hyp_init_context(void)
2116 {
2117 kvm_init_host_cpu_context(host_data_ptr(host_ctxt));
2118 kvm_init_host_debug_data();
2119
2120 if (!is_kernel_in_hyp_mode())
2121 cpu_init_hyp_mode();
2122 }
2123
cpu_hyp_init_features(void)2124 static void cpu_hyp_init_features(void)
2125 {
2126 cpu_set_hyp_vector();
2127
2128 if (is_kernel_in_hyp_mode()) {
2129 kvm_timer_init_vhe();
2130 kvm_debug_init_vhe();
2131 }
2132
2133 if (vgic_present)
2134 kvm_vgic_init_cpu_hardware();
2135 }
2136
cpu_hyp_reinit(void)2137 static void cpu_hyp_reinit(void)
2138 {
2139 cpu_hyp_reset();
2140 cpu_hyp_init_context();
2141 cpu_hyp_init_features();
2142 }
2143
cpu_hyp_init(void * discard)2144 static void cpu_hyp_init(void *discard)
2145 {
2146 if (!__this_cpu_read(kvm_hyp_initialized)) {
2147 cpu_hyp_reinit();
2148 __this_cpu_write(kvm_hyp_initialized, 1);
2149 }
2150 }
2151
cpu_hyp_uninit(void * discard)2152 static void cpu_hyp_uninit(void *discard)
2153 {
2154 if (!is_protected_kvm_enabled() && __this_cpu_read(kvm_hyp_initialized)) {
2155 cpu_hyp_reset();
2156 __this_cpu_write(kvm_hyp_initialized, 0);
2157 }
2158 }
2159
kvm_arch_enable_virtualization_cpu(void)2160 int kvm_arch_enable_virtualization_cpu(void)
2161 {
2162 /*
2163 * Most calls to this function are made with migration
2164 * disabled, but not with preemption disabled. The former is
2165 * enough to ensure correctness, but most of the helpers
2166 * expect the later and will throw a tantrum otherwise.
2167 */
2168 preempt_disable();
2169
2170 cpu_hyp_init(NULL);
2171
2172 kvm_vgic_cpu_up();
2173 kvm_timer_cpu_up();
2174
2175 preempt_enable();
2176
2177 return 0;
2178 }
2179
kvm_arch_disable_virtualization_cpu(void)2180 void kvm_arch_disable_virtualization_cpu(void)
2181 {
2182 kvm_timer_cpu_down();
2183 kvm_vgic_cpu_down();
2184
2185 if (!is_protected_kvm_enabled())
2186 cpu_hyp_uninit(NULL);
2187 }
2188
2189 #ifdef CONFIG_CPU_PM
hyp_init_cpu_pm_notifier(struct notifier_block * self,unsigned long cmd,void * v)2190 static int hyp_init_cpu_pm_notifier(struct notifier_block *self,
2191 unsigned long cmd,
2192 void *v)
2193 {
2194 /*
2195 * kvm_hyp_initialized is left with its old value over
2196 * PM_ENTER->PM_EXIT. It is used to indicate PM_EXIT should
2197 * re-enable hyp.
2198 */
2199 switch (cmd) {
2200 case CPU_PM_ENTER:
2201 if (__this_cpu_read(kvm_hyp_initialized))
2202 /*
2203 * don't update kvm_hyp_initialized here
2204 * so that the hyp will be re-enabled
2205 * when we resume. See below.
2206 */
2207 cpu_hyp_reset();
2208
2209 return NOTIFY_OK;
2210 case CPU_PM_ENTER_FAILED:
2211 case CPU_PM_EXIT:
2212 if (__this_cpu_read(kvm_hyp_initialized))
2213 /* The hyp was enabled before suspend. */
2214 cpu_hyp_reinit();
2215
2216 return NOTIFY_OK;
2217
2218 default:
2219 return NOTIFY_DONE;
2220 }
2221 }
2222
2223 static struct notifier_block hyp_init_cpu_pm_nb = {
2224 .notifier_call = hyp_init_cpu_pm_notifier,
2225 };
2226
hyp_cpu_pm_init(void)2227 static void __init hyp_cpu_pm_init(void)
2228 {
2229 if (!is_protected_kvm_enabled())
2230 cpu_pm_register_notifier(&hyp_init_cpu_pm_nb);
2231 }
hyp_cpu_pm_exit(void)2232 static void __init hyp_cpu_pm_exit(void)
2233 {
2234 if (!is_protected_kvm_enabled())
2235 cpu_pm_unregister_notifier(&hyp_init_cpu_pm_nb);
2236 }
2237 #else
hyp_cpu_pm_init(void)2238 static inline void __init hyp_cpu_pm_init(void)
2239 {
2240 }
hyp_cpu_pm_exit(void)2241 static inline void __init hyp_cpu_pm_exit(void)
2242 {
2243 }
2244 #endif
2245
init_cpu_logical_map(void)2246 static void __init init_cpu_logical_map(void)
2247 {
2248 unsigned int cpu;
2249
2250 /*
2251 * Copy the MPIDR <-> logical CPU ID mapping to hyp.
2252 * Only copy the set of online CPUs whose features have been checked
2253 * against the finalized system capabilities. The hypervisor will not
2254 * allow any other CPUs from the `possible` set to boot.
2255 */
2256 for_each_online_cpu(cpu)
2257 hyp_cpu_logical_map[cpu] = cpu_logical_map(cpu);
2258 }
2259
2260 #define init_psci_0_1_impl_state(config, what) \
2261 config.psci_0_1_ ## what ## _implemented = psci_ops.what
2262
init_psci_relay(void)2263 static bool __init init_psci_relay(void)
2264 {
2265 /*
2266 * If PSCI has not been initialized, protected KVM cannot install
2267 * itself on newly booted CPUs.
2268 */
2269 if (!psci_ops.get_version) {
2270 kvm_err("Cannot initialize protected mode without PSCI\n");
2271 return false;
2272 }
2273
2274 kvm_host_psci_config.version = psci_ops.get_version();
2275 kvm_host_psci_config.smccc_version = arm_smccc_get_version();
2276
2277 if (kvm_host_psci_config.version == PSCI_VERSION(0, 1)) {
2278 kvm_host_psci_config.function_ids_0_1 = get_psci_0_1_function_ids();
2279 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_suspend);
2280 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_on);
2281 init_psci_0_1_impl_state(kvm_host_psci_config, cpu_off);
2282 init_psci_0_1_impl_state(kvm_host_psci_config, migrate);
2283 }
2284 return true;
2285 }
2286
init_subsystems(void)2287 static int __init init_subsystems(void)
2288 {
2289 int err = 0;
2290
2291 /*
2292 * Enable hardware so that subsystem initialisation can access EL2.
2293 */
2294 on_each_cpu(cpu_hyp_init, NULL, 1);
2295
2296 /*
2297 * Register CPU lower-power notifier
2298 */
2299 hyp_cpu_pm_init();
2300
2301 /*
2302 * Init HYP view of VGIC
2303 */
2304 err = kvm_vgic_hyp_init();
2305 switch (err) {
2306 case 0:
2307 vgic_present = true;
2308 break;
2309 case -ENODEV:
2310 case -ENXIO:
2311 /*
2312 * No VGIC? No pKVM for you.
2313 *
2314 * Protected mode assumes that VGICv3 is present, so no point
2315 * in trying to hobble along if vgic initialization fails.
2316 */
2317 if (is_protected_kvm_enabled())
2318 goto out;
2319
2320 /*
2321 * Otherwise, userspace could choose to implement a GIC for its
2322 * guest on non-cooperative hardware.
2323 */
2324 vgic_present = false;
2325 err = 0;
2326 break;
2327 default:
2328 goto out;
2329 }
2330
2331 if (kvm_mode == KVM_MODE_NV &&
2332 !(vgic_present && (kvm_vgic_global_state.type == VGIC_V3 ||
2333 kvm_vgic_global_state.has_gcie_v3_compat))) {
2334 kvm_err("NV support requires GICv3 or GICv5 with legacy support, giving up\n");
2335 err = -EINVAL;
2336 goto out;
2337 }
2338
2339 /*
2340 * Init HYP architected timer support
2341 */
2342 err = kvm_timer_hyp_init(vgic_present);
2343 if (err)
2344 goto out;
2345
2346 kvm_register_perf_callbacks(NULL);
2347
2348 out:
2349 if (err)
2350 hyp_cpu_pm_exit();
2351
2352 if (err || !is_protected_kvm_enabled())
2353 on_each_cpu(cpu_hyp_uninit, NULL, 1);
2354
2355 return err;
2356 }
2357
teardown_subsystems(void)2358 static void __init teardown_subsystems(void)
2359 {
2360 kvm_unregister_perf_callbacks();
2361 hyp_cpu_pm_exit();
2362 }
2363
teardown_hyp_mode(void)2364 static void __init teardown_hyp_mode(void)
2365 {
2366 bool free_sve = system_supports_sve() && is_protected_kvm_enabled();
2367 int cpu;
2368
2369 free_hyp_pgds();
2370 for_each_possible_cpu(cpu) {
2371 if (per_cpu(kvm_hyp_initialized, cpu))
2372 continue;
2373
2374 free_pages(per_cpu(kvm_arm_hyp_stack_base, cpu), NVHE_STACK_SHIFT - PAGE_SHIFT);
2375
2376 if (!kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu])
2377 continue;
2378
2379 if (free_sve) {
2380 struct cpu_sve_state *sve_state;
2381
2382 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2383 free_pages((unsigned long) sve_state, pkvm_host_sve_state_order());
2384 }
2385
2386 free_pages(kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu], nvhe_percpu_order());
2387
2388 }
2389 }
2390
do_pkvm_init(u32 hyp_va_bits)2391 static int __init do_pkvm_init(u32 hyp_va_bits)
2392 {
2393 void *per_cpu_base = kvm_ksym_ref(kvm_nvhe_sym(kvm_arm_hyp_percpu_base));
2394 int ret;
2395
2396 preempt_disable();
2397 cpu_hyp_init_context();
2398 ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size,
2399 num_possible_cpus(), kern_hyp_va(per_cpu_base),
2400 hyp_va_bits);
2401 cpu_hyp_init_features();
2402
2403 /*
2404 * The stub hypercalls are now disabled, so set our local flag to
2405 * prevent a later re-init attempt in kvm_arch_enable_virtualization_cpu().
2406 */
2407 __this_cpu_write(kvm_hyp_initialized, 1);
2408 preempt_enable();
2409
2410 return ret;
2411 }
2412
get_hyp_id_aa64pfr0_el1(void)2413 static u64 get_hyp_id_aa64pfr0_el1(void)
2414 {
2415 /*
2416 * Track whether the system isn't affected by spectre/meltdown in the
2417 * hypervisor's view of id_aa64pfr0_el1, used for protected VMs.
2418 * Although this is per-CPU, we make it global for simplicity, e.g., not
2419 * to have to worry about vcpu migration.
2420 *
2421 * Unlike for non-protected VMs, userspace cannot override this for
2422 * protected VMs.
2423 */
2424 u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
2425
2426 val &= ~(ID_AA64PFR0_EL1_CSV2 |
2427 ID_AA64PFR0_EL1_CSV3);
2428
2429 val |= FIELD_PREP(ID_AA64PFR0_EL1_CSV2,
2430 arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED);
2431 val |= FIELD_PREP(ID_AA64PFR0_EL1_CSV3,
2432 arm64_get_meltdown_state() == SPECTRE_UNAFFECTED);
2433
2434 return val;
2435 }
2436
kvm_hyp_init_symbols(void)2437 static void kvm_hyp_init_symbols(void)
2438 {
2439 kvm_nvhe_sym(id_aa64pfr0_el1_sys_val) = get_hyp_id_aa64pfr0_el1();
2440 kvm_nvhe_sym(id_aa64pfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64PFR1_EL1);
2441 kvm_nvhe_sym(id_aa64isar0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR0_EL1);
2442 kvm_nvhe_sym(id_aa64isar1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR1_EL1);
2443 kvm_nvhe_sym(id_aa64isar2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
2444 kvm_nvhe_sym(id_aa64mmfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
2445 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
2446 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1);
2447 kvm_nvhe_sym(id_aa64smfr0_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64SMFR0_EL1);
2448 kvm_nvhe_sym(__icache_flags) = __icache_flags;
2449 kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits;
2450
2451 /* Propagate the FGT state to the the nVHE side */
2452 kvm_nvhe_sym(hfgrtr_masks) = hfgrtr_masks;
2453 kvm_nvhe_sym(hfgwtr_masks) = hfgwtr_masks;
2454 kvm_nvhe_sym(hfgitr_masks) = hfgitr_masks;
2455 kvm_nvhe_sym(hdfgrtr_masks) = hdfgrtr_masks;
2456 kvm_nvhe_sym(hdfgwtr_masks) = hdfgwtr_masks;
2457 kvm_nvhe_sym(hafgrtr_masks) = hafgrtr_masks;
2458 kvm_nvhe_sym(hfgrtr2_masks) = hfgrtr2_masks;
2459 kvm_nvhe_sym(hfgwtr2_masks) = hfgwtr2_masks;
2460 kvm_nvhe_sym(hfgitr2_masks) = hfgitr2_masks;
2461 kvm_nvhe_sym(hdfgrtr2_masks)= hdfgrtr2_masks;
2462 kvm_nvhe_sym(hdfgwtr2_masks)= hdfgwtr2_masks;
2463
2464 /*
2465 * Flush entire BSS since part of its data containing init symbols is read
2466 * while the MMU is off.
2467 */
2468 kvm_flush_dcache_to_poc(kvm_ksym_ref(__hyp_bss_start),
2469 kvm_ksym_ref(__hyp_bss_end) - kvm_ksym_ref(__hyp_bss_start));
2470 }
2471
kvm_hyp_init_protection(u32 hyp_va_bits)2472 static int __init kvm_hyp_init_protection(u32 hyp_va_bits)
2473 {
2474 void *addr = phys_to_virt(hyp_mem_base);
2475 int ret;
2476
2477 ret = create_hyp_mappings(addr, addr + hyp_mem_size, PAGE_HYP);
2478 if (ret)
2479 return ret;
2480
2481 ret = do_pkvm_init(hyp_va_bits);
2482 if (ret)
2483 return ret;
2484
2485 free_hyp_pgds();
2486
2487 return 0;
2488 }
2489
init_pkvm_host_sve_state(void)2490 static int init_pkvm_host_sve_state(void)
2491 {
2492 int cpu;
2493
2494 if (!system_supports_sve())
2495 return 0;
2496
2497 /* Allocate pages for host sve state in protected mode. */
2498 for_each_possible_cpu(cpu) {
2499 struct page *page = alloc_pages(GFP_KERNEL, pkvm_host_sve_state_order());
2500
2501 if (!page)
2502 return -ENOMEM;
2503
2504 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state = page_address(page);
2505 }
2506
2507 /*
2508 * Don't map the pages in hyp since these are only used in protected
2509 * mode, which will (re)create its own mapping when initialized.
2510 */
2511
2512 return 0;
2513 }
2514
2515 /*
2516 * Finalizes the initialization of hyp mode, once everything else is initialized
2517 * and the initialziation process cannot fail.
2518 */
finalize_init_hyp_mode(void)2519 static void finalize_init_hyp_mode(void)
2520 {
2521 int cpu;
2522
2523 if (system_supports_sve() && is_protected_kvm_enabled()) {
2524 for_each_possible_cpu(cpu) {
2525 struct cpu_sve_state *sve_state;
2526
2527 sve_state = per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state;
2528 per_cpu_ptr_nvhe_sym(kvm_host_data, cpu)->sve_state =
2529 kern_hyp_va(sve_state);
2530 }
2531 }
2532 }
2533
pkvm_hyp_init_ptrauth(void)2534 static void pkvm_hyp_init_ptrauth(void)
2535 {
2536 struct kvm_cpu_context *hyp_ctxt;
2537 int cpu;
2538
2539 for_each_possible_cpu(cpu) {
2540 hyp_ctxt = per_cpu_ptr_nvhe_sym(kvm_hyp_ctxt, cpu);
2541 hyp_ctxt->sys_regs[APIAKEYLO_EL1] = get_random_long();
2542 hyp_ctxt->sys_regs[APIAKEYHI_EL1] = get_random_long();
2543 hyp_ctxt->sys_regs[APIBKEYLO_EL1] = get_random_long();
2544 hyp_ctxt->sys_regs[APIBKEYHI_EL1] = get_random_long();
2545 hyp_ctxt->sys_regs[APDAKEYLO_EL1] = get_random_long();
2546 hyp_ctxt->sys_regs[APDAKEYHI_EL1] = get_random_long();
2547 hyp_ctxt->sys_regs[APDBKEYLO_EL1] = get_random_long();
2548 hyp_ctxt->sys_regs[APDBKEYHI_EL1] = get_random_long();
2549 hyp_ctxt->sys_regs[APGAKEYLO_EL1] = get_random_long();
2550 hyp_ctxt->sys_regs[APGAKEYHI_EL1] = get_random_long();
2551 }
2552 }
2553
2554 /* Inits Hyp-mode on all online CPUs */
init_hyp_mode(void)2555 static int __init init_hyp_mode(void)
2556 {
2557 u32 hyp_va_bits;
2558 int cpu;
2559 int err = -ENOMEM;
2560
2561 /*
2562 * The protected Hyp-mode cannot be initialized if the memory pool
2563 * allocation has failed.
2564 */
2565 if (is_protected_kvm_enabled() && !hyp_mem_base)
2566 goto out_err;
2567
2568 /*
2569 * Allocate Hyp PGD and setup Hyp identity mapping
2570 */
2571 err = kvm_mmu_init(&hyp_va_bits);
2572 if (err)
2573 goto out_err;
2574
2575 /*
2576 * Allocate stack pages for Hypervisor-mode
2577 */
2578 for_each_possible_cpu(cpu) {
2579 unsigned long stack_base;
2580
2581 stack_base = __get_free_pages(GFP_KERNEL, NVHE_STACK_SHIFT - PAGE_SHIFT);
2582 if (!stack_base) {
2583 err = -ENOMEM;
2584 goto out_err;
2585 }
2586
2587 per_cpu(kvm_arm_hyp_stack_base, cpu) = stack_base;
2588 }
2589
2590 /*
2591 * Allocate and initialize pages for Hypervisor-mode percpu regions.
2592 */
2593 for_each_possible_cpu(cpu) {
2594 struct page *page;
2595 void *page_addr;
2596
2597 page = alloc_pages(GFP_KERNEL, nvhe_percpu_order());
2598 if (!page) {
2599 err = -ENOMEM;
2600 goto out_err;
2601 }
2602
2603 page_addr = page_address(page);
2604 memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size());
2605 kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu] = (unsigned long)page_addr;
2606 }
2607
2608 /*
2609 * Map the Hyp-code called directly from the host
2610 */
2611 err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start),
2612 kvm_ksym_ref(__hyp_text_end), PAGE_HYP_EXEC);
2613 if (err) {
2614 kvm_err("Cannot map world-switch code\n");
2615 goto out_err;
2616 }
2617
2618 err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_start),
2619 kvm_ksym_ref(__hyp_data_end), PAGE_HYP);
2620 if (err) {
2621 kvm_err("Cannot map .hyp.data section\n");
2622 goto out_err;
2623 }
2624
2625 err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
2626 kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
2627 if (err) {
2628 kvm_err("Cannot map .hyp.rodata section\n");
2629 goto out_err;
2630 }
2631
2632 err = create_hyp_mappings(kvm_ksym_ref(__start_rodata),
2633 kvm_ksym_ref(__end_rodata), PAGE_HYP_RO);
2634 if (err) {
2635 kvm_err("Cannot map rodata section\n");
2636 goto out_err;
2637 }
2638
2639 /*
2640 * .hyp.bss is guaranteed to be placed at the beginning of the .bss
2641 * section thanks to an assertion in the linker script. Map it RW and
2642 * the rest of .bss RO.
2643 */
2644 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_start),
2645 kvm_ksym_ref(__hyp_bss_end), PAGE_HYP);
2646 if (err) {
2647 kvm_err("Cannot map hyp bss section: %d\n", err);
2648 goto out_err;
2649 }
2650
2651 err = create_hyp_mappings(kvm_ksym_ref(__hyp_bss_end),
2652 kvm_ksym_ref(__bss_stop), PAGE_HYP_RO);
2653 if (err) {
2654 kvm_err("Cannot map bss section\n");
2655 goto out_err;
2656 }
2657
2658 /*
2659 * Map the Hyp stack pages
2660 */
2661 for_each_possible_cpu(cpu) {
2662 struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
2663 char *stack_base = (char *)per_cpu(kvm_arm_hyp_stack_base, cpu);
2664
2665 err = create_hyp_stack(__pa(stack_base), ¶ms->stack_hyp_va);
2666 if (err) {
2667 kvm_err("Cannot map hyp stack\n");
2668 goto out_err;
2669 }
2670
2671 /*
2672 * Save the stack PA in nvhe_init_params. This will be needed
2673 * to recreate the stack mapping in protected nVHE mode.
2674 * __hyp_pa() won't do the right thing there, since the stack
2675 * has been mapped in the flexible private VA space.
2676 */
2677 params->stack_pa = __pa(stack_base);
2678 }
2679
2680 for_each_possible_cpu(cpu) {
2681 char *percpu_begin = (char *)kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu];
2682 char *percpu_end = percpu_begin + nvhe_percpu_size();
2683
2684 /* Map Hyp percpu pages */
2685 err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP);
2686 if (err) {
2687 kvm_err("Cannot map hyp percpu region\n");
2688 goto out_err;
2689 }
2690
2691 /* Prepare the CPU initialization parameters */
2692 cpu_prepare_hyp_mode(cpu, hyp_va_bits);
2693 }
2694
2695 kvm_hyp_init_symbols();
2696
2697 if (is_protected_kvm_enabled()) {
2698 if (IS_ENABLED(CONFIG_ARM64_PTR_AUTH_KERNEL) &&
2699 cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH))
2700 pkvm_hyp_init_ptrauth();
2701
2702 init_cpu_logical_map();
2703
2704 if (!init_psci_relay()) {
2705 err = -ENODEV;
2706 goto out_err;
2707 }
2708
2709 err = init_pkvm_host_sve_state();
2710 if (err)
2711 goto out_err;
2712
2713 err = kvm_hyp_init_protection(hyp_va_bits);
2714 if (err) {
2715 kvm_err("Failed to init hyp memory protection\n");
2716 goto out_err;
2717 }
2718 }
2719
2720 return 0;
2721
2722 out_err:
2723 teardown_hyp_mode();
2724 kvm_err("error initializing Hyp mode: %d\n", err);
2725 return err;
2726 }
2727
kvm_mpidr_to_vcpu(struct kvm * kvm,unsigned long mpidr)2728 struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
2729 {
2730 struct kvm_vcpu *vcpu = NULL;
2731 struct kvm_mpidr_data *data;
2732 unsigned long i;
2733
2734 mpidr &= MPIDR_HWID_BITMASK;
2735
2736 rcu_read_lock();
2737 data = rcu_dereference(kvm->arch.mpidr_data);
2738
2739 if (data) {
2740 u16 idx = kvm_mpidr_index(data, mpidr);
2741
2742 vcpu = kvm_get_vcpu(kvm, data->cmpidr_to_idx[idx]);
2743 if (mpidr != kvm_vcpu_get_mpidr_aff(vcpu))
2744 vcpu = NULL;
2745 }
2746
2747 rcu_read_unlock();
2748
2749 if (vcpu)
2750 return vcpu;
2751
2752 kvm_for_each_vcpu(i, vcpu, kvm) {
2753 if (mpidr == kvm_vcpu_get_mpidr_aff(vcpu))
2754 return vcpu;
2755 }
2756 return NULL;
2757 }
2758
kvm_arch_irqchip_in_kernel(struct kvm * kvm)2759 bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
2760 {
2761 return irqchip_in_kernel(kvm);
2762 }
2763
kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2764 int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
2765 struct irq_bypass_producer *prod)
2766 {
2767 struct kvm_kernel_irqfd *irqfd =
2768 container_of(cons, struct kvm_kernel_irqfd, consumer);
2769 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2770
2771 /*
2772 * The only thing we have a chance of directly-injecting is LPIs. Maybe
2773 * one day...
2774 */
2775 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2776 return 0;
2777
2778 return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
2779 &irqfd->irq_entry);
2780 }
2781
kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer * cons,struct irq_bypass_producer * prod)2782 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
2783 struct irq_bypass_producer *prod)
2784 {
2785 struct kvm_kernel_irqfd *irqfd =
2786 container_of(cons, struct kvm_kernel_irqfd, consumer);
2787 struct kvm_kernel_irq_routing_entry *irq_entry = &irqfd->irq_entry;
2788
2789 if (irq_entry->type != KVM_IRQ_ROUTING_MSI)
2790 return;
2791
2792 kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq);
2793 }
2794
kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd * irqfd,struct kvm_kernel_irq_routing_entry * old,struct kvm_kernel_irq_routing_entry * new)2795 void kvm_arch_update_irqfd_routing(struct kvm_kernel_irqfd *irqfd,
2796 struct kvm_kernel_irq_routing_entry *old,
2797 struct kvm_kernel_irq_routing_entry *new)
2798 {
2799 if (old->type == KVM_IRQ_ROUTING_MSI &&
2800 new->type == KVM_IRQ_ROUTING_MSI &&
2801 !memcmp(&old->msi, &new->msi, sizeof(new->msi)))
2802 return;
2803
2804 /*
2805 * Remapping the vLPI requires taking the its_lock mutex to resolve
2806 * the new translation. We're in spinlock land at this point, so no
2807 * chance of resolving the translation.
2808 *
2809 * Unmap the vLPI and fall back to software LPI injection.
2810 */
2811 return kvm_vgic_v4_unset_forwarding(irqfd->kvm, irqfd->producer->irq);
2812 }
2813
kvm_arch_irq_bypass_stop(struct irq_bypass_consumer * cons)2814 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
2815 {
2816 struct kvm_kernel_irqfd *irqfd =
2817 container_of(cons, struct kvm_kernel_irqfd, consumer);
2818
2819 kvm_arm_halt_guest(irqfd->kvm);
2820 }
2821
kvm_arch_irq_bypass_start(struct irq_bypass_consumer * cons)2822 void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
2823 {
2824 struct kvm_kernel_irqfd *irqfd =
2825 container_of(cons, struct kvm_kernel_irqfd, consumer);
2826
2827 kvm_arm_resume_guest(irqfd->kvm);
2828 }
2829
2830 /* Initialize Hyp-mode and memory mappings on all CPUs */
kvm_arm_init(void)2831 static __init int kvm_arm_init(void)
2832 {
2833 int err;
2834 bool in_hyp_mode;
2835
2836 if (!is_hyp_mode_available()) {
2837 kvm_info("HYP mode not available\n");
2838 return -ENODEV;
2839 }
2840
2841 if (kvm_get_mode() == KVM_MODE_NONE) {
2842 kvm_info("KVM disabled from command line\n");
2843 return -ENODEV;
2844 }
2845
2846 err = kvm_sys_reg_table_init();
2847 if (err) {
2848 kvm_info("Error initializing system register tables");
2849 return err;
2850 }
2851
2852 in_hyp_mode = is_kernel_in_hyp_mode();
2853
2854 if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) ||
2855 cpus_have_final_cap(ARM64_WORKAROUND_1508412))
2856 kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \
2857 "Only trusted guests should be used on this system.\n");
2858
2859 err = kvm_set_ipa_limit();
2860 if (err)
2861 return err;
2862
2863 err = kvm_arm_init_sve();
2864 if (err)
2865 return err;
2866
2867 err = kvm_arm_vmid_alloc_init();
2868 if (err) {
2869 kvm_err("Failed to initialize VMID allocator.\n");
2870 return err;
2871 }
2872
2873 if (!in_hyp_mode) {
2874 err = init_hyp_mode();
2875 if (err)
2876 goto out_err;
2877 }
2878
2879 err = kvm_init_vector_slots();
2880 if (err) {
2881 kvm_err("Cannot initialise vector slots\n");
2882 goto out_hyp;
2883 }
2884
2885 err = init_subsystems();
2886 if (err)
2887 goto out_hyp;
2888
2889 kvm_info("%s%sVHE%s mode initialized successfully\n",
2890 in_hyp_mode ? "" : (is_protected_kvm_enabled() ?
2891 "Protected " : "Hyp "),
2892 in_hyp_mode ? "" : (cpus_have_final_cap(ARM64_KVM_HVHE) ?
2893 "h" : "n"),
2894 cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) ? "+NV2": "");
2895
2896 /*
2897 * FIXME: Do something reasonable if kvm_init() fails after pKVM
2898 * hypervisor protection is finalized.
2899 */
2900 err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
2901 if (err)
2902 goto out_subs;
2903
2904 /*
2905 * This should be called after initialization is done and failure isn't
2906 * possible anymore.
2907 */
2908 if (!in_hyp_mode)
2909 finalize_init_hyp_mode();
2910
2911 kvm_arm_initialised = true;
2912
2913 return 0;
2914
2915 out_subs:
2916 teardown_subsystems();
2917 out_hyp:
2918 if (!in_hyp_mode)
2919 teardown_hyp_mode();
2920 out_err:
2921 kvm_arm_vmid_alloc_free();
2922 return err;
2923 }
2924
early_kvm_mode_cfg(char * arg)2925 static int __init early_kvm_mode_cfg(char *arg)
2926 {
2927 if (!arg)
2928 return -EINVAL;
2929
2930 if (strcmp(arg, "none") == 0) {
2931 kvm_mode = KVM_MODE_NONE;
2932 return 0;
2933 }
2934
2935 if (!is_hyp_mode_available()) {
2936 pr_warn_once("KVM is not available. Ignoring kvm-arm.mode\n");
2937 return 0;
2938 }
2939
2940 if (strcmp(arg, "protected") == 0) {
2941 if (!is_kernel_in_hyp_mode())
2942 kvm_mode = KVM_MODE_PROTECTED;
2943 else
2944 pr_warn_once("Protected KVM not available with VHE\n");
2945
2946 return 0;
2947 }
2948
2949 if (strcmp(arg, "nvhe") == 0 && !WARN_ON(is_kernel_in_hyp_mode())) {
2950 kvm_mode = KVM_MODE_DEFAULT;
2951 return 0;
2952 }
2953
2954 if (strcmp(arg, "nested") == 0 && !WARN_ON(!is_kernel_in_hyp_mode())) {
2955 kvm_mode = KVM_MODE_NV;
2956 return 0;
2957 }
2958
2959 return -EINVAL;
2960 }
2961 early_param("kvm-arm.mode", early_kvm_mode_cfg);
2962
early_kvm_wfx_trap_policy_cfg(char * arg,enum kvm_wfx_trap_policy * p)2963 static int __init early_kvm_wfx_trap_policy_cfg(char *arg, enum kvm_wfx_trap_policy *p)
2964 {
2965 if (!arg)
2966 return -EINVAL;
2967
2968 if (strcmp(arg, "trap") == 0) {
2969 *p = KVM_WFX_TRAP;
2970 return 0;
2971 }
2972
2973 if (strcmp(arg, "notrap") == 0) {
2974 *p = KVM_WFX_NOTRAP;
2975 return 0;
2976 }
2977
2978 return -EINVAL;
2979 }
2980
early_kvm_wfi_trap_policy_cfg(char * arg)2981 static int __init early_kvm_wfi_trap_policy_cfg(char *arg)
2982 {
2983 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfi_trap_policy);
2984 }
2985 early_param("kvm-arm.wfi_trap_policy", early_kvm_wfi_trap_policy_cfg);
2986
early_kvm_wfe_trap_policy_cfg(char * arg)2987 static int __init early_kvm_wfe_trap_policy_cfg(char *arg)
2988 {
2989 return early_kvm_wfx_trap_policy_cfg(arg, &kvm_wfe_trap_policy);
2990 }
2991 early_param("kvm-arm.wfe_trap_policy", early_kvm_wfe_trap_policy_cfg);
2992
kvm_get_mode(void)2993 enum kvm_mode kvm_get_mode(void)
2994 {
2995 return kvm_mode;
2996 }
2997
2998 module_init(kvm_arm_init);
2999